Tuesday, June 30, 2015

Stuff our brain makes up

kw: book reviews, nonfiction, psychology, neuroscience, hallucination

To hallucinate is to be human…and, perhaps, to be any creature with a mind. As we read in Hallucinations by Oliver Sacks, a great many stresses and neurological disorders can lead to sensing (any of the "5 senses" may be involved) things that aren't there, but for many of us, so can a great many rather prosaic matters. For example, many people are like me: almost any time I can close my eyes and I will either see things—including persons—or hear voices that aren't there. Particularly when I am sleepy, these phantasms can be quite detailed: I'll either see entire scenes being enacted or hear entire conversations (though I can seldom understand the words), or music, and sometimes sight and sound go together. Also when I am sleepy or tired, I don't necessarily have to close my eyes to hallucinate. It is likely that these kinds of things happen at times for most of us. (I was once asked why I rarely listen to music. I replied that I have a sound track running almost all the time.)

Hallucinations could be considered both a travelogue and a catalog of hallucinatory perceptions. Dr. Sacks has migraine auras; he has experimented with sundry drugs; he has suffered griefs and stresses that led to several hallucinatory episodes. While many disease syndromes, from high fevers to Parkinsonism, lead to hallucinations, I was particularly interested in the more "normal" cases. It seems that the brain's pattern matching and recognition systems easily go into overdrive, as many of us experience when we look at clouds and see all kinds of fantasies. Static images get "over-recognized" rather easily. I have a painting of a seascape, with waves and rocks; one of the rocks one day looked just like a jaguar's head to me, and I can't see it any other way now. But we also experience things for which there is no apparent external trigger. Perhaps it is the lack of a trigger that triggers them, such as closing one's eyes.

By the way, the author mentions tinnitus, or "ringing in the ears" as a kind of hallucination caused by damage to the inner ear, and the brain hallucinates the sounds it is not receiving from the organ. This may be so in some cases, but certainly not all. I have low-level tinnitus, which gets louder if a pull my head back a certain distance. An audiologist used a tiny microphone in my ear to listen in, and said that pulling my head back changed the shape of the middle ear, which amplified the sound. The cause is the damaged hair cells vibrating in response to random noise (Brownian motion), not being damped as is normally the case. The inner ear may be a super-regenerative amplifier, which I'll discuss in a moment.

It may be that the only time most of us are free of hallucinations is when we are in a most ordinary state, not bored, not over-engaged, just "doing something" that fits well within our comfort zone, mentally and emotionally. I like the concept of the comfort zone, particularly in this context. Its boundary may be quite firm for some of us, and rather more nuanced for others. In my case, I think of the boundary as a wide zone of gradually increasing stress, and throughout most of this range any shift can release a mild hallucination of some sort. Thus the tendency to hallucinate in this "normal" way follows a sort of spectrum.

I think of a mechanical/electronic example. A kind of radio receiver, used in older CB radios, is "super-regenerative". It has three circuits in its detector portion. One is an extra-sensitive amplifier that will oscillate and almost blow itself out when any signal of the right frequency appears, including noise. It has extremely high positive feedback, but the key is that it "pops" faster the stronger the input signal. The second is a squelch circuit that allows the amplifier to "go crazy" for about 1/20,000th of a second, then very briefly cuts its power. The amount of squelch can be set by the operator. The third measures the maximum level achieved during each tiny time slice, and turns that series of measurements into an audio signal. So you can think of a hallucinating brain as a super-regenerative receiver with the squelch set too low.

A characteristic of most hallucinations is that you know it. A hallucination taken as real is a delusion. One question raised a few times in the book is whether the human tendency to religious faith is based entirely on hallucinations. Of course, to a total rationalist, all religion is delusional. But total rationalists are quite rare. According to Julian Jaynes (see The Origin of Consciousness in the Breakdown of the Bicameral Mind), half our brain informed the other half of its sensings and learnings via hallucinations that were thought to embody the voices or appearances of deities. Further evolution caused these two functions to become better integrated. Some say the tendency to generate divine apparitions and voices are a remainder of the bicameral mind, leading to every form of religious experience. I personally think that is an over-interpretation, and that there really is a God, but I'll forego theology in this review.

Hallucinations of all kinds are a class of experience that stands alongside dreams and imagination. They resemble dreams but can be much more detailed. Some dreams can be directed; this is called lucid dreaming. Hallucinations can't be directed, and usually play out as though the hallucinator is a spectator in someone else's theater. Imagination is nearly always directed but typically lacks the apparent veracity of a hallucination. We imagine something and may even speak of "seeing it in the mind's eye", but it doesn't appear to project into the world outside the way a hallucination does. Hallucination is also related to synesthesia, and perhaps this is its closest cousin. A synesthete might see colors attached to musical notes or printed numbers or letters; or to be able to taste the sound of certain words or songs.

But hallucination is more than mixed perception. It is perception without a perceived object, a result that is quite different from the stimulus that might produce it. For example, in a healthy person, grief can trigger the sight and/or sound of the lost loved one. This kind of hallucination is most directly related to a perceived object, or the memory of one. But the "sleepy-time" hallucinations I have aren't based on any proximal object, nor memory, except, I suppose, my general fund of memories about prior events. Thus, they might be waking dreams, though they differ from dreams during sleep, which are usually accompanied by a feeling of purpose. Hallucinations are typically purposeless.

I had a great time reading an earlier book by Oliver Sacks (reviewed in May). Hallucinations was a bit harder to read through. The writing is often more analytical, written at a higher level, and perhaps a bit more detailed at times than I had tolerance for. However, I don't want to commit the error of the king who told Mozart, "There are too many notes." Mozart rightly replied (so it is reported), "Majesty, which notes should have been left out?" This book can be read with profit by anyone, and will provide particular comfort to those who may be seeing or hearing "things", and fear they are crazy. No, you aren't crazy if you know your hallucination from what is really "out there". Or, if you are crazy, then so are we all.

Sunday, June 21, 2015

Walk on the wild side - on Main Street

kw: book reviews, nonfiction, wildlife, cities

Do children still sing "Skip to my Lou"? One verse repeats, "Pigs in the parlor/What'll I do?". Other verses mention flies in the buttermilk, a cat in the cream jar, and a couple of birds. If you want to get creative, verses could be added about coyotes or deer in the back yard, cottontails in the corncrib, and if you were in Cape Town, baboons in the kitchen.

Most people in the cities tend to think of the city as a pretty sterile place, inhabited only by humans and their pets, maybe with pigeons and sparrows around, and a few pests such as flies thrown in. Tristan Donovan is here to tell us there is more to cities than we might imagine, in Feral Cities: Adventures with Animals in the Urban Jungle.

Much of the book contains stories about animals, not just in suburban areas and city fringes, but right in the middle of our cities around the world: Boars in Berlin, Coyotes in Chicago, the resident Cougar in Griffith Park in Los Angeles, a flock of Parrots in Brooklyn, Baboons breaking into homes in Cape Town, and the finding by researchers in Raleigh that every home is host to at least 100 species of insects and spiders.

Why should there be animals in our cities? By making cities comfortable for humans, we have made them comfortable for a multitude of opportunistic animals. In the U.S., northern cities are warmer, sometimes as much as 10°F and even more. Further south, many spaces are air conditioned, so an overheated jaybird in Tucson might make its way into the local WalMart to cool off. Cities in dry places are wetter, and homes in wet places are drier, than their surroundings. Snakes have been found with half their bodies hanging into a hot tub on a cool night, occasionally diverting a human romantic encounter from its intended course. And there is food everywhere, everywhere! Raccoons raiding garbage cans. Crows and gulls picking at road kill. Rats in the storm sewers, eating our refuse and being hunted by snakes and coyotes and wildcats. To a bobcat a rat's intended purpose is turning our crap into his lunch.

Biologists have compared animals in cities with their rural counterparts, and have found that many species are more abundant, better fed and live longer in a city than in the countryside. Why wouldn't there be animals in our cities?

I really like the turn taken in the last couple of chapters. We ought to be making our cities more friendly to species we like. For most people, a little time spent watching rabbits or otters is calming. My wife was quite delighted one day to report seeing a deer "pronking" down our street outside our hedge. A few endangered species are actually doing better in cities than in their "native" habitat. The Peregrine Falcons nesting on window ledges in skyscrapers come to mind (Bookmark the DuPont FalconCam and take a look beginning next March; just now I see only feathers in the nest).

Many doctrinaire environmentalists might shudder at the thought of making our cities into better habitat for beneficial or endangered animals. To them, cities are Evil and part of the probem; there's no way they can be part of the solution. But face it, cities are here to stay. They presently encumber only 2% of the land area, but that is growing, and their impact is greater than you might think. A certain parrot species is found in greater numbers in certain southwestern U.S. cities than in its entire home range in Mexico. They go where the living is better!

And suppose we were to succeed in creating cities in which nothing could live except humans and a short list of "approved" human pets. Then what? Should inner city kids—and their parents—be deprived of the sight of a blue jay, cardinal or indigo bunting? Should they be doomed never to see a living rabbit or raccoon? Should the endangered parrots of the U.S. southwest be "repatriated" to a "native" habitat that is getting too degraded to support them?

I don't like flies in my home, so I welcome the spiders that live here. There are at least 10 species that I've found. Only when a spider gets too big and is found crawling on the bed do I evict her. Our yard hosts rabbits and squirrels, so I do have to put small-mesh fencing around the garden, and we hope for the occasional visit by a fox to keep their numbers in check (she comes through every couple of years). We see deer droppings under the apple tree in the fall. As long as I don't corner a deer and get clipped by those front hooves, I'm happy to have one bed down there occasionally. We're planting a greater variety of flowers to draw butterflies, but avoiding the "butterfly bush" which is too concentrated and becomes a praying mantis colony beneath which one finds piles of butterfly wings! When I find a robin nest in the hedge, that section goes an extra month without being clipped until the chicks fledge. We let wasps nest in the louvers of the attic vents, but not in areas where children might play. Wasps are great predators of the insects I don't want to encounter. We encourage dragonflies, which keep the mosquito population down. A local hawk "tends to" the various little mammals such as mice and voles.

I appreciate the biologists who agree with Mr. Donovan, and are working to make our cities better for human-animal coexistence. Of course we don't want rats everywhere, but the best exterminators are Maine Coon cats, not poison baits that kill so many other animals as a byproduct, and make rat bodies poisonous to house cats and wild cats. With proper education we can even learn to live with coyotes in our midst...and we aren't going to see those exterminated anytime soon, anyway! Nearby New Jersey residents need to learn to think like bears so they don't attract them where they don't want them, but do attract them where they do want them. We need to face it, humans are part of nature. Let's open up to seeing "who else" shares our cities.

A very education and refreshing book.

Friday, June 19, 2015

The Grand-daddy of ancient master myths

kw: book reviews, nonfiction, investigations, Atlantis

Ah, the Good Old Days. Like many "golden agers" I tend to dote on the past. I rather obsessively gather old family photos, the older the better, and scan them or re-photograph whole album and scrapbook pages. But I'm not totally in thrall to allure of a past seen through rose-colored spectacles. There are some periods, including a near-decade, that I'd rather not have gone through, thank you very much. I still think of one period as "the lost years."

I think myself more level-headed than most folks, and I know I am less deluded about supposed glories of past times than a great many. For some, supposed historical greatness has become a religion. In the Watchman Index of Cults and Religions, more than 1,400 groups are described, usually very briefly. Among these, in particular, 393 (more than a quarter) are "New Age", relying on an eclectic mix of ancient "Eastern Wisdom" beliefs and whatever is new about alternative healing whether of body or mind. There are also a couple dozen that focus more specifically on "Ancient Master" beliefs. Those that don't trace these Masters to Tibet, mostly trace them to Atlantis.

Freelance investigator Mark Adams caught the Atlantis bug several years ago, and did his best to track down the most credible (! of a mostly incredible group) leading figures among fans of Atlantis. Right away we can set aside flying saucers, stories of aircars and Star Trek-level technology existing on an enormous, mysterious island some 10,000 years ago. He has done an excellent job of gathering the evidence most likely to be level-headed, and written of his journey/pilgrimage in Meet Me in Atlantis: My Obsessive Quest to Find the Sunken City.

The book has 29 chapters and a Preface, and focuses first on finding the "best" witnesses, then on visiting a handful of candidate locations that might have either been Atlantis, or given rise to the story Plato wrote 2,400 years ago. As Plato wrote, using another's voice, his ancestor Solon visited Egypt about 600 BCE and was told of an ancient and powerful city/continent that was destroyed in a day by a great cataclysm, 9,000 years earlier. The most important facts we can glean are:

  • Atlantis was "beyond the Pillars of Hercules", probably referring to the Strait of Gibraltar, and thus most likely in the Atlantic Ocean rather than the Mediterranean Sea, though some argue strongly that the Pillars were further east.
  • Atlantis warred with ancient Athens and other Mediterranean city-states until its destruction 9,600 years ago. Nobody has shown that Athens was anything close to a city at that time.
  • The catastrophe was both an earthquake and great flood, followed by the land mostly sinking under the sea. This is often interpreted as an earthquake and tsumani, but others think of a comet or asteroid impact somewhat less devastating than the one that eliminated the dinosaurs.

The most reasoned voice in the whole matter is that of Tony O'Connell, of atlantipedia.ie (in Ireland). Adams mentions several others, most of whom he visited and interviewed. There are several candidate sites for a genuinely sunken city or civilization, without resorting to an Australia-sized continent a few hundred miles west of Spain. Cadiz, Spain is one of two located on the Spanish coast, places that clearly suffered a tsunami or something similar, that washed lots of land into the sea, which is one way to interpret "sunken". Another is in Morocco, though it lies a bit too far uphill. The most likely to me is Thera/Santorini, some 85 miles (140 km) north of Crete, which exploded in about 1600BCE. What is left is less than half the original island, a crescent surrounding a drowned crater with a little volcanic cone near its center, now called Santorini.

It is helpful at this point to consider the "other ring of fire", the Mediterranean area. First focus attention on the Triple Junction at Afar, where the Red Sea, the East African Rift, and the Gulf of Aden intersect. This is a tectonic spreading center. The colors on the map indicate spreading in RED, transform faulting in GREEN, and convergence in BLUE. The MAUVE color represents ambiguity in the direction of motion. The little numbers show plate movement, in mm/yr, relative to Africa, which has probably been relatively motionless and is used as a reference. The image is from this article by Catherine Ross. The greatest relative motion is the convergence that is shrinking the Mediterranean Sea by 3.7 cm/year, or about a meter each 27 years (That Sea is some 2.4 m narrower than when I was born, around 8 feet). This is quite similar to the convergence off/under Japan that led to the Fukushima earthquake and tsunami.

The Mediterranean Sea is thus a hotbed of tectonic activity, making earthquakes and floods frequent enough to have spawned numerous disaster legends, without the help of comets. Some may recall the great earthquake in Anchorage, Alaska in 1964. There, a large chunk of land was pushed up about 20 feet (over 6 m) and another section sank an equal amount. You can have an earthquake of similar size along the blue trace above, about every three centuries. That is lots of time for multiple disasters to enter the collective consciousness and be conflated into a story that Plato could recount, with little or no embellishment, as a cautionary tale to attach to his Republic. There have been several comparable disasters since the time of Plato, including Thera.

Did Plato believe the Atlantis tale was true? It is hard to psychologize a great thinker face-to-face, much less so at a 2,400-year remove. Whether he believed it or not, he must have hoped his audience would believe enough of it to amend their ways. Instead, things may have improved in a technological way, but have, if anything, gotten worse in the realm of politics and political wisdom. Those who now take the Atlantis story seriously tend to go much too far, over-interpreting Plato's morality tale into an over-hyped depiction of a golden age even better, perhaps, than Eden.

I suppose I could also have titled this post "Nostalgia on Steroids".

Saturday, June 13, 2015

Does Nature care that we want to save it?

kw: book reviews, nonfiction, nature, biodiversity, invasive species

I lived on Lake Erie through most of the 1960's. During my high school years I worked at Cedar Point in the summertime. When we moved to Ohio I recall being told that the "sewage treatment system" for Cleveland was a series of pipes five miles long that took raw sewage out into Lake Erie. We took a boat tour on the Cuyahoga River to see all the bridges and buildings and how cargo vessels had to negotiate turn after turn to get to the docks. It seems they were continually spilling bilge and oil as they did so. The oil and sludge on top of the river was about four inches thick. We learned after we moved away that the river caught fire in 1969.

Lake Erie was effectively dead in those years. Oh, there were a few kinds of fish that could tolerate the pollution, mostly carp and other kinds that weren't worth catching to eat. We were warned not to swim when there was a north wind: sewage would blow ashore. The water was gray, and if you put your hand more than half a foot down you couldn't see it. One of my teachers liked to SCUBA dive in a "deeper" part of the western lake: the western quarter of Lake Erie is usually only six feet deep (less than 2m), but in a few areas it gets 20-30 feet deep, yet there are "reefs", or shallow spots that come near the surface, but they aren't visible in the murky water. In class one day he told us of being "down there" and hearing a loud crunch. He ascended and found that a yacht had run aground on a reef. He helped the old fellow get loose. The next day's newspaper had a little notice that the president of the Rocky River Yacht Club had been helped by a local teacher after "his yacht struck a submerged object." He laughed and told us, "That submerged object was the bottom of the lake!"

Fast forward twenty years. In 1988 a few specimens of a little freshwater clam from Russia called a Zebra Mussel were found in Lake Erie. Soon they were everywhere, covering the bottom, clogging drains and other equipment, and basically wreaking havoc. The little ZM's were also accused of driving the native species of lake shellfish and algae and some finfish nearly to extinction. Actually, looking back, it is clear that those declining natives were on the way out and would have succumbed before the mid-1990's, but something happened to the lake first. Zebra Mussels, as all mussels and clams, are filter feeders. ZM's happen to tolerate pollution better than almost any other freshwater bivalve. In their quest for plankton (tiny water creatures like amoebas and diatoms), each animal filters a quart of water daily. It takes out not only the plankton but many organic pollution particles also (like raw sewage - yum!). Multiply by a few tens of billions: the whole lake was getting filtered through the ZM's every week or two.

In a few years the water was noticeably clearer. The last time I saw the lake, you could see to the bottom in six feet of water, and I was told visibility is 20 feet or more in most of the lake. Cleaner water meant the native clams and mussels got healthier and staged a comeback, including those thought to be extinct. More algae now grow there because light penetrates farther. The nearly extinct lake sturgeon is rebounding. Sturgeons eat mussels, and seem to relish the ZM's. So do a few other kinds of fish such as smallmouth bass. Lake Erie is alive again. All due to a "dangerous invasive alien" that had the entire environmental movement in a tizzy for decades.

The new book by journalist Fred Pearce, The New Wild: Why Invasive Species Will Be Nature's Salvation, is full of such stories. I cribbed a few of the details above from his account, which is based on the published record. He also writes of the Guanacaste trees, the national tree of Costa Rica, which was on the verge of extinction. Its seeds need to pass through the gut of a large mammal and be partially digested to germinate, but all large mammals had been extirpated—by humans—and the trees only existed because humans had been planting the seeds. Some would grow if their shell rotted enough after planting. Seeds left lying on the ground just piled up like so many rocks. An ecologist puzzling over what to do suggested introducing horses to the area, and it worked. That fellow saved a beloved tree from extinction, but paradoxically earned himself the hatred of multitudes of doctrinaire "environmentalists.

Pearce writes of the forests of Puerto Rico, restoring themselves on land that was abandoned after plantations of sugar (and other crops) went bust. But they are not restoring themselves with the tree species that grew there before; those cannot tolerate soil changed by a few centuries of plantation cultivation. No, "alien"tree species that had been introduced or otherwise appeared in Puerto Rico over the generations, and were growing here and there, spread quickly over the disturbed land and created a new kind of forest. Later some native species were able to return also. To an untrained eye, it looks the same as the fragments of "original" forest elsewhere on the island.

To be fair, Pearce also tells of places that have suffered after certain alien species arrived. Seafarers that arrive anywhere seem always to have rats along. Some rats grasp the opportunity to go ashore. On occasion, havoc results, and they eat everything in sight, including the eggs and young of many native species. There have indeed been extinctions of endemic species on some islands and other restricted areas. Colonial America is a prime example, and one species that was nearly extincted in Virginia was the colonists, after the rats they had inadvertently allowed ashore ate through their grain stores!

Whether carried by humans or not, species have a way of getting around. As described by Alan de Queiroz in The Monkey's Journey (reviewed here), long-distance dispersal by all kinds of unlikely species happens over and over again. Of course, things that fly or float travel better than more sedentary critters, but one need look no farther than Hawaii for an example: the archipelago has many endemic species of both plant and animal, species that evolved there, and it has never been in contact with a continent, nor even closer than a couple of thousand miles. All the endemics of Hawaii are descended from animals and plants that traveled, or were taken, long distances.

Think about this: Every time a new species arrived in Hawaii and began to reproduce there, it was an "invasive alien" species. By the time the Polynesians, now Hawaiians, had been there a few dozen generations, and the first Europeans arrived, what looked like primeval forest to the Europeans was about half consisting of species the Polynesians brought with them. Since then, more and more aliens have arrived. Some, such as the giant African tree snail, are doing damage. Most have just found a way to fit into the existing ecology, have done little or no harm, and have actually enriched Hawaiian biodiversity.

This introduces a major theme of The New Wild. "Alien" does not mean "Evil". It all depends. Even seemingly evil aliens, such as the Zebra Mussel, can do good in the end. ZM's are now part of the ecology of the Great Lakes whether we like it or not. To eradicate them now would cost a great deal more than it would have cost us, by purely technological means, to clean up Lake Erie, and we couldn't even afford that! The "evil invaders" cleaned it up, but not quite for free: industries do have the cost of cleaning mussel shells off their water intake pipes and other submerged equipment.

There's a nature center we visit from time to time. On a guided tour the ranger moaned about their problems with Multiflora Roses. I guess they were originally transplanted there to start briar patches where there had been none. As it happens, Multiflora can tolerate the pollution and drought associated with the way the land had been left before the nature center was set up. Native roses from the area cannot. But now, Multiflora is considered an "invasive alien" and they are trying to root out all the rose bushes. They can't do it. It is a Hydra problem (harking to the Hydra of Hercules). If you dig out a rose bush, you leave disturbed soil behind, and Multiflora just love disturbed soil. Rose hips or fragments of root left behind typically engender several new bushes where there had been only one. One step forward, four steps back!

So what is the New Wild? It is best understood by contrast to the Old Wild, a world of wild places untouched by humans. Old-growth forests. Pristine landscapes. Primeval territories that actually have not existed for tens of thousands of years. The Old Wild exists only in our imaginations. The New Wild is a new understanding of how nature works on lands that vary from little-managed to extensively-managed to wholly cultivated, in all of which nature does what nature always does.

"Nature" is a mythical embodiment of the myriad environments and their living denizens. We think of the "forest primeval", such as the deep woods of Maine referred to by Longfellow in Evangeline, as a virgin product of nature. Humans have been in Maine, as they have been throughout the Americas, for at least 13,000 years. The Maine forests in the 1400's may have been less heavily managed than the maize-farming areas along the Delaware River, but managed they were, for the rather modest timber needs of the Penobscot people. Without people, what would the forest have been like? There is no way to know.

We do know that the forests of the northern 2/3 of North America, even those that have been little used by Euro-Americans since 1492, are substantially different now than before, because of a much-beloved (by most) group of alien species: earthworms. The silent-treading natives of legend and lore had something going for them that is seldom found now, a thick layer of moldering leaves on the forest floor. Wherever there is water enough for fallen leaves to remain a bit moist, they are soon consumed by earthworms. But this was not so from about 15,000 years ago until the 1600's when Europeans brought European earthworms ashore. This was usually not deliberate; worms came in the soil around the roots of plants brought by the colonists. Native North American earthworm species are found only in the southern half of the U.S. and further south; the northern half of the country was scraped clean of its entire biosphere by glaciers, and the native worms travel too slowly to have re-colonized the north in only 10,000 years. Earthworms are one of the most successful groups of invasive alien species. We are better off for them.

A second theme of the book is that current environmental dogma, that it is best to root out and exterminate all alien invaders, is usually wrong-headed. He gives numerous examples that show how "invasions" usually increase overall biodiversity of the invaded landscape; how the supposed extinctions the aliens are accused of causing were usually already accomplished by the time of the invasion; and how the ZM is but one example of a much-feared alien species that turned out to be a blessing in disguise and actually contributed to the overall health of the environment.

There is one metaphor that Charles Darwin used, which we must do away with: Nature as 10,000 tightly-hammered wedges. He wrote of inter-species competition as the removal of one wedge so a different one could fit in. This is not so. Take careful note: THIS IS NOT SO. Rather than many wedges tightly filling all space, think of Nature as a field with many plants growing, yet not all the ground is covered (even in a well-fertilized lawn you can see dirt between the blades). Perhaps there are 100 species of plants in this field. Cast in some seeds of another 100 species and wait a year. Then count the species growing there. Not all of the new seeds will have done well, and you may find only 75 of the 100 new species has taken root. And the original 100? You may not find every one of the original 100 species, but chances are, they are all there if you examine all the field carefully.

I recall taking a young man from Beijing on a field trip in 1984. It was only in 1980 that Chinese students were first permitted to study in American universities, so he was one of the early ones. He was a real city boy. We drove from Rapid City, SD to Billings, MT, the northern way, along US 212 through Custer National Forest (it ought to be named for Crazy Horse, IMHO) and two Indian Reservations. He saw cattle for the first time (beeves are also a hugely successful invasive species in America). Later he saw pronghorn antelopes among the cattle. I told him what they were, and he asked, "Don't they fight?" I replied that there was grass enough for both, plus the pronghorn would eat cacti and many kinds of wildflowers that beef cattle prefer not to eat. So although a state like Wyoming or Montana might have more beeves than humans, the native ungulates have not been driven to extinction. Had we passed through the national forest at dusk, we'd probably have also seen deer.

A few of the examples in the book have numbers, and they show how the usual result of multiple invasions is for species diversity to increase by 50% to 100%, both of plants and animals. An "ecology" is not a finely-tuned instrument, nor a finite collection of tightly-packed wedges, but a more fluid situation. Adding dozens or even hundreds of new species is unlikely (except on a few very small islands) to result in the extinction of any endemic species, and the new species fit in, forming a new assemblage that works as well, or often better, than before. Nature is not static. Left entirely alone, things change continually, and new species arrive while existing ones die away, from any particular patch of ground. Change is the only constant!

I've rattled on long enough. The New Wild is not quite a call to arms on behalf of a new understanding of the environment, but it is intended to open eyes to a new way of seeing nature. It is unlikely to change the minds of the old guard with their idée fixe of exterminating all alien species. It represents a growing understanding, which I hope will prevail quickly (and more quickly as that old guard retires and passes on). People tend to jump to conclusions. Influential people jump just as quickly as everyone else, which makes them dangerous. Remember the adage, "Haste makes waste." I add to it, "A sense of urgency is the Devil's tool." Y'gotta think things through. Fred Pearce has given us a book full of reasons for thinking through our environmental premises.

Monday, June 08, 2015

Anatomy without all the dissection

kw: book reviews, nonfiction, nature, illustrations

I sometimes wish I'd have kept up the drawing I did as a child. A lack of eye-hand coordination meant quick drawings weren't accurate, and to draw a good likeness of anything was much too time-consuming. I sometimes marvel at the drawing skills of naturalists, pre-eminently Roger Tory Peterson, whose Field Guide series sets a very high standard for nature illustrating. Nature Anatomy: The Curious Parts & Pieces of the Natural World, written and illustrated by Julia Rothman is not quite a field guide, so much as an enthusiast's collection of nature arcana, illustrated in a more cartoonish style.

The "anatomy" is primarily external, no dissecting knife needed. This illustration of the parts of a flower from page 62, and a cutaway of Earth on pages 14-15, are about as "deep" as it gets.

Many more pages are devoted to catalogs of interesting specimens from every natural realm, at least for critters and plants larger than an inch or so. There is a good illustration of the various kinds of feathers on a bird, and one of the external anatomy of a typical insect, using an ant. This page of butterflies of interest to the author is typical.

A book such as this is not intended to convey lots of knowledge. Indeed, if you add up the words, they amount to a small chapter. Rather, it introduces the reader/viewer to all the breadth of living things. Quite an enjoyable book.

Saturday, June 06, 2015

Foremost Zoologist writes about Botany

kw: book reviews, nonfiction, botany, love of plants, exhortation

Jane Goodall is one of my favorite people. Her discoveries about chimpanzees turned primatology and anthropology on its head, not just once but several times. Even more, her tireless quest to drive world leaders and citizens to a better balance with nature continues to touch a chord in me and in many.

One might ask, what is a Zoologist doing writing about plants? For every animal you study, you must study its relationships, not only within its species but with other animal species such as prey or predators, and nearly always with the plants in its environment. Even a pure carnivore such as a big cat uses plants for concealment, for bedding and so forth. And now that biology has turned more and more to the study of trophic cascades (If you have never seen this video about Yellowstone, stop and watch it now!), every life is seen to depend on plants, and every life, particularly of keystone species, affects the life cycles of plants in its environment.

Dr. Goodall is a writer of rare skill, and for this and a few other recent books she has teamed up with Gail Hudson to produce a volume that matches the best 19th Century writing, Seeds of Hope: Wisdom and Wonder From the World of Plants. The book is one part her historical and lyrical paean to the plants and their landscapes that she has loved in her long life, one part historical and social survey, and one part (or two!) hortatory essays that exhort us all to take better care of a biosphere the human race is rapidly driving to ruin. Her voice is lyrical without being maudlin, high and clear without being shrill.

Anyone who has lived more than 25-30 years, and has not seen substantial changes in nearly every landscape with which they are familiar, must have lived a cloistered prisoner all those years. I visited Suguaro National Park nearly 50 years ago, when it looked a lot like the image on the left in this montage:

On the right, in 1910, the difference is shocking. Look particularly in the background, where the mountain foothills are being covered with creeping suburbs near Tucson, Arizona (Photo montage from this article by Betty Mason in Wired).

Her message boils down to something simple: "Hey, World, please, please slow down and think more long-term. You billionaires don't need another billion or ten billion quite that fast, and people's needs can be taken care of without destroying everything around them until ultimately they and you will also suffer destruction."

I don't think there is anything I could add to that. Rather, I'll take a side note, and answer some who might know me well, how conservative I am, and say, "Huh?" Did you know that the root of "Conservative" is the word "Conserve"? Did you know that the national park system was begun by Conservatives? Strangely, Theodore Roosevelt is being called a Progressive in recent biographies and documentaries, but he sure wasn't thought of as a "progressive" a century ago or so! He's just being called that because today's neo-progressives can't imagine that someone with conservative values would do the things he did. A true conservative is not a short-term thinker, but a strategic thinker. Trouble is, there just are too darn few of them left to be found in national and international politics. A conservative who is not an environmentalist (a true environmentalist, not a fuzzy-headed tree-hugger), cannot honestly claim the title Conservative.

'Nuff said. Read the book.

Wednesday, May 27, 2015

Some leading ladies of science

kw: book reviews, nonfiction, short biographies, women, science

My parents knew who Hedy Lamarr was; she starred in more than 20 American films in the 1940s and 1950s, after being a film star in Europe beginning in 1930. They didn't know she held the patent for spread-spectrum radio, a critical technology for secure communications. I learned of it in the 1960s after her work was declassified.

What other women of science did I learn of? Naturally, my mother had the books by Irene Joliot-Curie, so I knew of Madame Curie and her nearly-forgotten husband Pierre, and or Irene herself. Working only the memory banks here (Boy! Am I tempted to rely on Google…):

  • Being a computer programmer for 40 years, it is a slam dunk that I'd know about Admiral Grace Hopper, a founder of the COBOL language, who is credited with changing our word for a machine error from "glitch" to "bug"…and pasted the wayward moth into her notebook.
  • And of course, Ada Lovelace, who wrote the first computer program, for Charles Babbage's Analytical Engine, a machine that is a whole lot easier to emulate in software than to actually build of brass gears and ratchets.
  • Being a DuPont-er, I knew of Stephanie Kwolek, inventor of Kevlar®. Wish I'd had the chance to meet her while she was still at the company.
  • I have met Ellen Kullman, current CEO of DuPont, who began as a mechanical engineer.
  • I read Silent Spring by Rachel Carson, and later a few of her essays.
  • I read of "jumping genes" in a popular article by Barbara McClintock, and later the monographs in which she reported her work.
  • Emmy Noether, honored by Alfred Einstein for cracking the math needed for his general theory of relativity.
  • Florence Nightingale, who used statistics to show that battlefield hospitals were a hundred times as deadly as enemy bullets, and reformed nursing practice as a result.
  • Lise Meitner, a physicist on a par with Bohr and Heisenberg.
  • Rosalind Franklin, who would be the discoverer of the Double Helix if she hadn't been undercut by her boss.
  • Lynn Margulis, who first explained how complex eukaryotic cells developed from collaborations among simpler prokaryotic cells (known today as bacteria).
  • Sylvia Earle, in my opinion the most innovative practicing oceanographer.
  • Sally Ride, the first American woman astronaut.
  • Teacher Christa McAuliffe, who died aboard the Challenger when it blew up.
  • Primatologist Jane Goodall, whose most recent book will be reviewed here in a few days.
  • Primatologist Dian Fossey, who did for gorillas what Goodall did for chimps.

That's 16, and I could probably dig deeper, but time won't allow. With the help of good library work, Rachel Swaby has gathered biographical material for 52 of the best women scientists for her book Headstrong: 52 Women Who Changed Science—and the World. In her introduction she explains why she included only deceased women, so three people on my list above could not have appeared, though I wish she'd included Fossey. She also explains that the incredible fame of Marie Curie made it rather moot to include her, though she did include her daughter Irene.

Thus we learn of Alice Ball, who concocted the first practical, injectable serum of chaulmoogra oil to treat leprosy; Emilie de Chatelet (sorry I left off the accents), who translated Newton's Principia into French, and wrote a commentary about the same size; Annie Jump Cannon, who practically created the Henry Draper Catalog of Stellar Spectra by classifying nearly 400,000 stars, also pretty much creating the classification criteria as she went; and Marie Tharp, whose work resurrected the theory of continental drift that is now called Plate Tectonics. I guess I could add Tharp above as a 17th; I read articles she wrote with Bruce Heezen in 1970.

It was enjoyable reading, but I think I'd have been more pleased were the book a third longer. Many of the mini-biographies are barely two pages, and the style would suit Joe Friday ("Just the facts, please."). It is a good beginning towards restoring a historical imbalance in science reporting. It wouldn't be a bad idea for a copy of this book to make its way into every middle school girl's backpack.

Saturday, May 23, 2015

The specialness of islands

kw: book reviews, nonfiction, medicine, islands, cycads

Perception may not be reality, but it certainly feels that way. We go through life contentedly thinking other people are a lot like us. The growth from naivete to sophistication is largely involved in learning the ways we differ from others, and how to effectively cope with that. When we say someone "sees things differently", we usually mean understanding, not a different kind of physical vision. But among people who are not entirely blind, one man in twelve, and one woman in about 250, sees the world around as having different colors than those seen by most of us.

This illustration from 1895 is an attempt to show people with "normal" color vision the effects of a few kinds of color blindness. A truer depiction would have both flags II and III with brown stripes, just of differing contrast, and flags IV and V would be blurrier, because the blue-blind and total monochromats have much lower acuity of vision. Note that in flag IV the star field is black rather than blue.

I once studied color vision for 50 of my colleagues using printed color wheels, asking them to name the colors at certain angles, marked around the margin of the wheel. I tracked down a few folks who were color blind also, because the aim was to produce color maps for geologists that everyone could use with equal ease, and many geologists are color blind. As it happened, the results were somewhat confounded by the printing process, which used three colored inks. These are easier to distinguish from one another even by people with the usual, red-green, kinds of color blindness. Thus, we had  more flexibility using map colors than we'd originally expected.

What do we mean by red-green color blindness? It is actually of two varieties. The formal terms are protanopia and deuteranopia, based on the numbers 1 and 2. "1" refers to the red-sensitive cone cell (R cone), and "2" refers to the green-sensitive cone cell (G cone). However, the sensitivity curves of these two kinds of cells overlap quite a lot.

As seen in this diagram, the R cone and G cone have very similar sensitivity curves, just shifted from one another. It is somewhat surprising that the B cone has such a low sensitivity. In normal daylight, there is a lot of blue light, so it doesn't need a lot of sensitivity. In low light, such as the light of a full moon, for humans at least, the rod cells begin to work as the cones lose effectiveness. Rods are also blue-sensitive, though sort of between G cones and B cones. This is why moonlit scenes appear bluish. The most sensitive vision cells active under moonlight are blue-sensitive.

If either the R cones or G cones are missing or inactive, red, yellow and green shades can be distinguished from blues, but not from each other. The main difference is that the deepest reds appear totally dark to a protanope, while there is a blue-green region of the spectrum that is hard for a deuteranope to see. But because both conditions make the person unable to distinguish red from green, both are called red-green color blindness.

If none of the cones are present, or are not active, a person has only "night vision", with only the rods working. This is the primary type of achromatopsia, or total color blindness. The word is composed of "achromat", meaning "no color" and "opsia", referring to the eye. According to an old estimate, about one person in 30,000 has this condition, and it occurs in more men much more than women. Apparently, all kinds of color anomaly and color blindness are X-linked, so it is quite rare for a woman to have the same anomalous gene on both X chromosomes.

Because the "day vision" system isn't working, and rod cells typically bleach out entirely in bright light and stop working, achromatopes are day-blind or very sensitive to bright light, and cannot function in daylight without strong filters over their eyes. There are other unfortunate characteristics of the syndrome, such as nystagmus (rapid and unusual movement of the eyes), which may be side effects of the day-blindness.

Oliver Sacks, a polymath who almost incidentally is a neurologist, became fascinated upon learning of a pair of islands in the south Pacific, where more than 5% of the people are achromatopes. In the local language the condition is called maskun, meaning "not see", because of their day-blindness. They can function well enough in lower light, so they can do certain kinds of work. They are well accepted in their communities. Dr. Sacks and two others, one a scientist named Knut Nordby who is an achromatope, visited Pingelap and Pohnpei to study the phenomenon, and to bring dark glasses and other vision aids to people that have been coping without them. Their travels and work are described in a delightful way in Sacks's book The Island of the Colorblind, bound together with Cycad Island in the volume I read.

Both books explore the way island populations tend to concentrate certain characteristics. When you have a small population that has little or no contact with others, the statistics of gene-shuffling through the generations can exaggerate some conditions. In the case of Pingelap, a disastrous typhoon and following famine killed all but 20 people residing there, and fear of disease kept people from neighboring islands from visiting for more than a generation. One of those 20 carried the gene for achromatopsia, and inbreeding brought it into expression, as mentioned, to an incidence of about 5%. The numbers of those with maskun would be greater if it were not hard for them to find marriage partners.

The presence of Dr. Nordby was crucial to getting the people to talk willingly about their condition, and to help the research team gather useful genealogical data. The largest nearby island, Pohnpei, has a valley populated by immigrants from Pingelap, and a similar incidence of maskun. The team also went there to help those they could, and study the condition further.

Color blindness of this kind is trouble enough, but it doesn't kill you. A different medical condition is found on Guam, as Dr. Sacks tells us in Cycad Island. A slow, progressive disease called lytico-bodig in the local language has been endemic there for several generations. In the lytico form it resembles ALS, most famously afflicting Dr. Stephen Hawking, and earlier called Lou Gehrig's Disease, for that ballplayer died from it. The bodig form is more like Parkinson's Disease, leading to rigidity and paralysis, and is often accompanied by dementia. One sufferer cheerfully told Dr. Sacks, "Come back soon. I won't remember you, so I'll have the pleasure of getting to know you all over again."

Much of the latter book details a series of frustrated efforts over the years to determine what causes lytico-bodig. No final conclusion is offered, but the language strongly hints that the best hypothesis is poisoning of people who are genetically susceptible, in two different ways, to certain chemicals in the resin of cycads. The residents of Guam enjoy certain foods they prepare from cycad seed pods and other parts of the plant. They go to great lengths to detoxify them, because untreated, a small amount can kill. It seems to be like Japanese fugu, the puffer-fish, which an expert chef can prepare so it is safe to eat, if a bit "tingly", but several people are badly injured or killed each year from eating fugu. On Guam, cycad preparation is carried out with various levels of diligence. Also, a local fruit bat eats cycad fruits, and something that concentrates in its flesh can be damaging to the people, who enjoy bat meals.

It is stated that nobody born after 1952 suffers from lytico-bodig. This is probably because of changes in diet. Cycads are eaten much less now, and the fruit bat is seldom eaten because it is getting very scarce. Thus, a resident scientist named John Steele, who has studied the disease and befriended its sufferers for half his life, may find that the disease vanishes before he is able to prove its source. This is scientifically frustrating, but socially, it is a great relief.

Dr. Sacks's interests are wide-ranging, and I find he has five other books in print. Guess I'll track them down.

Sunday, May 17, 2015

A well loved river in these parts

kw: book reviews, nonfiction, rivers, americana, culture, history, north american history

A friend thought it might be time that I learned more about the loveliest river in this area, so he gave me The Brandywine by Henry Seidel Canby, a book in the series "Rivers of America", edited primarily by Stephen Vincent Benét. The book was originally published in 1941; I read a paperback edition of 1969. The pen illustrations within are by Andrew Wyeth, and include sketch versions of paintings I've seen in the Brandywine River Museum and the Sanderson Museum. I live within a couple of miles of the Brandywine River, and I cross it via one bridge or another several times weekly. I also spend hours at a time along its banks in the gunpowder yards, so I guess it is high time!

Dr. Canby was born along the Brandywine in 1878, and though he spent many years as a professor at Yale, he returned to Wilmington frequently. We see through him this small, though significant river as it was between 75 and 130 years ago. Through both personal knowledge and wide reading he can trace the history and culture of the area as none other. In his childhood, though mills for making flour, textiles and gunpowder abounded, much of the Brandywine was still in a rather unspoiled state.

The forbidding geology had a lot to do with this; it was easier to build roads around the middle gorge than to try to cross it. If I recall correctly, Canby wrote that there were seven bridges crossing the river between Forks of the Brandywine in Pennsylvania and its confluence with the Christina River in Wilmington, a linear distance of about 14.5 miles, but more than 20 river miles. In that distance it descends more than 210 feet, a slope that averages roughly 10 feet per mile, but in the middle reaches it drops 33-34 feet per mile, making it one of the most favorable mill streams in the middle Atlantic region. It also means that what Canby calls "the gorge of the Brandywine" has some of the steepest terrain in northern Delaware and southern Chester County, Pennsylvania.

The author writes of the river as a lover of his beloved. He quotes other writers at some length, sometimes deploring their over-sentimentality, though he reflects it himself, just in the more restrained manner of a Yalie in all his dignity. It is a river worthy of much sentiment! During the days on which I volunteer in the yards at the Hagley Museum, situated in the steepest part of the gorge, I find the idle times are anything but onerous, being filled with visual delights backdropped by the rustle and grumble of the river.

It would not do justice to the book to simply catalog its 14 chapters. They are quite comprehensive. Rather, three items struck my fancy. Firstly, that the iconic "log cabin" was introduced by settlers along the Brandywine in the late 1600's, but did not spread beyond the area until nearly 1800. Elsewhere, and earlier here also, the vertical-log palisade was used where defense was needed, and various sorts of European structures otherwise, though they were usually quite unsuitable, particularly when badly constructed (the usual case). A log cabin is much easier for non-professionals to build into a sound and minimally drafty dwelling. Had Abraham Lincoln been born 5 or 10 years earlier, he would not have been born in a log cabin!

Secondly, there were no "Indian wars" along the river. Violent relations with native peoples were practically unknown here, and the great wars of legend took place many miles to the west and mainly after the Civil War. The Lenape and other "Delaware Indians" did find themselves exploited, but tended to complain through legal channels, and when they'd had enough most of them moved elsewhere of their own accord, primarily because of failure of the shad runs rather than violence. Nobody at the time understood clearly that all the mill dams were choking off the migration of the shad.

Thirdly, as already mentioned, in 1940 there were but 7 bridges along the lower Brandywine, and much of the river was comparatively unspoiled. Today fishermen are advised not to eat fish caught in the Brandywine anywhere south of the Forks, and by my count the bridges number 23: 17 road bridges, 3 foot bridges (one half collapsed) and 3 railroad trestles. There are also 9 mill dams still in existence, though only the 3 at Hagley are still in use to keep millraces filled. Compared to many mid-Atlantic rivers, though, the Brandywine still has significant unspoiled stretches. The existence of Brandywine Creek State Park protects one stretch of nearly 5 miles, and Hagley has kept another mile or so in a condition similar to that of 1921 when the mills closed.

I didn't yet  mention the Battle of the Brandywine, George Washington's failed attempt to keep the British from taking Philadelphia. Several good books about the battle had been published by 1940, so Canby gives a well-attested sketch of the engagements, but designedly leaves the details to others. The view from miles above: neither commander knew the area, nor had anyone with good local knowledge on staff; the farmers thereabouts were Quakers and were determined to help neither side of the conflict; scouts sent hither and yon brought conflicting reports; and the British were luckier in finding fords north of the Forks about which Washington was ignorant (as they also had been a day earlier), so they could flank the Colonials and get ahead of them. Thus, the British wintered in Philadelphia and the Colonial army in Valley Forge.

There is much, much more to the book, though it is less than 300 pages. To learn more of the river's geography, history of settlement, business growth, literature and art, and its role in American industrialization, you'll find this book a valuable and very entertaining resource.

Sunday, May 10, 2015

The folly of evangelical anti-theism

kw: book reviews, nonfiction, polemics, science, religion, faith, pseudoscience

The human ape is a religious animal. It is part of our evolutionary heritage and we cannot escape it. Given that we must, by our nature, dedicate ourselves to something, what shall that something be?

To be religious does not require belief in God or a god or gods. Buddhism, for example, says nothing about the existence of any deity. Taoism at best only hints that some kind of god may be behind the scenes; that "Tao" might be personalized.

Mathematician Amir D. Aczel writes about a book a year, and his offering for 2014 is Why Science Does Not Disprove God. Several debates and discussions about science and religion in which he participated provided the initial fodder for writing the book. While he makes it clear he does not believe in the Lord God described by a literalist reading of the Bible, he is sympathetic to religion and even favorable.

The thesis of the book is simple: It is a misuse of science and scientific methods when the New Atheists use them to claim, not only that there is no God, but that there cannot be any kind of god. Who are the New Atheists? In order according to noise level, chiefly Richard Dawkins, Daniel Dennett, Lawrence M. Krauss, Christopher Hitchens (deceased), and Sam Harris. While atheism has long been with us, what is comparatively new is the evangelical tone of at least these five (although evangelical atheism is not particularly new, as an apparent conflict in the 1760's between Leonard Euler and Denis Diderot illustrates).

Even more to the point: The past couple of decades have been marred by increasingly shrill denouncements of Western and Judaeo-Christian institutions by extremist Islamic clerics. Over the same period, Dawkins and others have become equally shrill in their anti-religious campaign. The language of Dawkins in particular is just as inflammatory as any fatwa by a shrieking Imam. (BTW, this is me speaking; Dr. Aczel is too gentlemanly to point this out.)

Anti-theist claims are many and complex. The book tackles the most serious abuses of science by these "scientific" atheists in twelve chapters; three other chapters limn the history of the relationship of religion and science, and deal with more general matters. Along the way, Dr. Aczel shows how the New Atheists have grossly misused archaeology, cosmology, mathematics, probability, evolutionary theory, and the philosophy of science. Put it all together, and what do you have? A new religion based on pseudo-science, whose adherents are just as fervent, even rabid, as the most bigoted Bible-thumper (and, sad to say, there are all to many of those).

Scientists tend to overstate the power of science. The best scientists are humble and humbly grateful that science works as well as it does in so many realms. Unfortunately, they are a minority; most are simply "science workers", getting results and publishing as often as possible without giving much thought to the philosophy of science. Even more unfortunately, those "best" are outnumbered by those who arrogate divine powers to science, expecting all questions to be answered, if only we gather enough evidence, theorize deeply enough, and perhaps one day craft a "Theory of Everything."

Dr. Aczel demonstrates that such claims are overblown. He invokes the following:

  • The Heisenberg Uncertainty Principle demonstrates that it is impossible to know with perfect accuracy both the position and the energy of a particle. Accuracy can be very, very good, but there are limits beyond which it will forever be impossible to measure. Even more, the Copenhagen Interpretation of Quantum Mechanics states that even in the absence of measurement, the precise path a particle will take has an irreducible amount of uncertainty. Diffraction in optical systems is evidence of this.
  • Chaos Theory describes nonlinear systems (those in which the ongoing process influences itself) that are hypersensitive to initial conditions. In practical terms, when such systems are described mathematically, the equations cannot be solved in what we call "closed form". The simplest such system is the gravitational Three-Body Problem. Certain special cases have been mathematically solved, but it has been proven (in the mathematical sense) that the general case cannot be solved. Numerical (computer) simulations can be crafted over a limited span of time and space, but they are always dogged by the accumulation of rounding errors, until those dominate the result, and you are no longer simulating the system you began with. Even in "linear" systems (those with no feedback), successive iterations of a computer simulation still accumulate rounding errors, and special methods must be used if you need to test the magnitude of those accumulated errors. That greatly increases the computational cost of such simulations. And wouldn't you know it: Nature presents very few linear systems.
  • The Schrödinger Wave Equation and other work by Edwin Schrödinger show that "things can go where you think they can't", and the poor cat of his paradox, being both dead and alive, actually illustrates our inability to know in detail the fate of any quantum event. By the way, I count the cat as an observer: it knows whether the cyanide got released, before the "official observer" opens the box to look.
  • The Incompleteness Theorem of Kurt Gödel shows that it is possible to ask questions that cannot be answered using the mathematical (or "formal") system in which the question was asked. For example, formal logic is full of paradoxes that require one to step outside the system to elucidate. A famous example is the Barber of Seville: He shaves all men in Seville who do not shave themselves. Who shaves the Barber? Of course, the question has no answer in the system as set up. But if we bring the matter into the real world, we find that, of course, the Barber is bearded and is not shaved at all. The false premise of the paradox is that all men in Seville are clean-shaven.

The anti-Theists have formed a new church. You could call it a religion without any of the benefits. Of course, I agree that religious motivations have led to great abuses. For political reasons, couched as religion but really in a land grab, a Medieval Pope wrote a death warrant for the entire population of a province (or was it 3 provinces?) in France. Some 3 million persons were to be slaughtered. This was not carried out. Anti-Theists invoke the Crusades. Again, the motives were a mixture of religion and politics; for political gain the leaders incited religious fervor in ignorant knights and peasants. In fact, the terrible abuses of the history of Christianity in Europe and the Near East can just as well be invoked to prove that politics are evil…and they are!

But let us not forget the greatest slaughters of history. Do the names Adolf Hitler, Pol Pot, Joseph Stalin and Mao Zedong mean anything to you? Atheists one and all, responsible for the deaths of tens of millions or, in the case of Mao, more than 100 million. Compared to any of these four (and a couple of others), the Pope mentioned above was a piker, even had his order been carried out.

But we must remember that today's New Atheists claim the mantle science. Dr. Aczel has shown that at best they skew their science, and more frequently they abuse it all out of recognition. To put it baldly, the New Atheists, today's anti-Theists, are charlatans.

What does God think of this? The first six verses of Psalm 2 provide a clue:

Why do the nations conspire
    and the peoples plot in vain?
The kings of the earth rise up
    and the rulers band together
    against the Lord and against his anointed, saying,
“Let us break their chains
    and throw off their shackles.”

The One enthroned in heaven laughs;
    the Lord scoffs at them.
He rebukes them in his anger
    and terrifies them in his wrath, saying,
“I have installed my king
    on Zion, my holy mountain.”

Wednesday, May 06, 2015

First Contact - bugs versus gods?

kw: book reviews, science fiction, first contact, china, cultural revolution

What could induce someone to such deep hatred for humanity, as to wish our total destruction? A good place to begin might be the Chinese "Great Leap Forward", known in the West as the Cultural Revolution (hereafter, CR). This great leap backward set China back about a century, and it was only because of a massive shift in political attitudes—facilitated by Mao's untimely death in 1976—that the nation has been able to (nearly) grow into a 21st Century superpower. Make no mistake, China's leaders are still committed Communists, but their social mind-control is only a whisker of what existed prior to the 1970's.

In The Three-Body Problem author Liu Cixin, using evocative and shocking prose, begins by setting the stage upon the background of the CR and a handful of persons so traumatized by it that they abandon hope that humanity can become upright and beneficent. One in particular, astrophysicist Ye Wenjie, determines a possible way to send a powerful signal to nearby stars using the Sun as an amplifier. When she gets a response more than 8 years later, a key element is in place. She devises a plan and eventually becomes titular leader of a group devoted to inviting the aliens to invade, and promising to collaborate with them in either reforming or destroying human society and perhaps the human race. As that sentence hints, there are factions within her organization, upon which much drama later in the book depends.

The star system thus contacted is commonly called Alpha Centauri, a 3-star system that is the "nearest star" to our solar system. Any planets of such a system are likely to have chaotic orbits, or at best alternating between stable and unstable orbits and thus climates. Thus the book's title. These aliens have strong motivation to move to a planet with a billions-of-years history of climatic stability, at least relative to theirs. They are called Trisolarians, for their three suns, and in late chapters are seen to have a considerable technological advantage over humans. I find that paradoxical; few of their hundreds of civilizations lasted longer than several generations, so how could they advance so far?

The book's translator, Ken Liu, writes in an afterword of the responsibility to provide not just a word-by-word translation (our different grammars don't really allow that anyway), but one that evokes emotions and illustrates concepts in such a way that the reader can partake of the author's thinking. (The author and translator are probably not closely related; Liu is the fourth most common Chinese surname.) For me, the writing is more straightforward than most modern English prose, which I found refreshing. It harked back to the fiction of my youth, when at least science fiction writers had fewer literary pretensions.

This is book one of a trilogy. All three have been translated, so I intend to track down the other two so I can see where the author is going, after closing with the foolishly arrogant message from the Trisolarians, "You're bugs!". However, their fleet will take four centuries to arrive. Can humanity achieve enough progress in that time to avert species-wide disaster? That is no settled matter, and curious Trisolarian AI's called Sophons may make it moot. I guess we must stay tuned.

For a Chinese writer to produce such a novel, in China, strongly indicates just how far that nation's leaders have moved from Maoist super-totalitarianism.

Sunday, May 03, 2015

All your little bitty bits

kw: book reviews, nonfiction, science, atoms, popular treatments

I weigh a bit over 200 pounds, about 91 kg. Dry me out, and the residue would weigh about 85 lbs or 38+ kg. One could then (someone with a sufficiently strong stomach) divide up the dry mass into bone and muscle and so forth. But what is my atomic composition? If you also have that question, you'll find out in Your Atomic Self: The Invisible Elements That Connect You to Everything Else in the Universe by Curt Stager.

You can also get an answer of sorts from this table, but what fun is a table? In Your Atomic Self we find out, not just the amounts of the major chemical elements in us, but something about where they came from, how long they spend as a part of us, (not as long as you think!), and where they go when they leave us, or, ultimately, when each of "us" leaves our body behind.

For example, you and I are 2/3 oxygen, by weight. Most of that is in the water that makes up roughly 50-60% of our total weight (depending on bone/muscle/fat ratios). Where did all that oxygen come from? Surprisingly, the water we drink doesn't all become body water. Much of it is dissociated by various processes and some exits the body, rather soon, in our breath as carbon dioxide. The foods we eat all contain lots of oxygen, so some of that winds up in our body water, some in our tissues (fats and bone contain lots of oxygen), and some also gets breathed out as CO2.

Though our lungs may have a capacity of half a gallon to a gallon (2-4 liters), we seldom breathe this deeply; less than one liter (1 quart) per breath is typical when we are at rest, which is nearly all the time for sedentary Westerners. About 20% of the air we breathe is oxygen, and all but 1% of the rest is nitrogen, which contributes to air pressure, but is not chemically active in this form—for which we ought to be very grateful! We use about 1/3 of the oxygen we breathe in and exhale the rest (which is why mouth-to-mouth resuscitation is effective). But at 20 breaths per minute, we allow nearly 30,000 liters of air in and out of our lungs daily, including about 5,800 liters of oxygen, of which about 2,000 liters enters our blood stream, and an equivalent amount, attached to carbon, exits as some 2,000 liters of CO2.

Did you ever realize that a liter of CO2 weighs 37.5% more than a liter of O2? You'd lose a lot of weight if you did nothing but breathe all day! (Not really a lot; about a kilogram.) But as the author writes, there is more to the story than that, and it is not only the amount of water you take in and excrete.

Not all molecules of oxygen, and not all molecules of CO2, are the same. Most oxygen is the isotope O-16, but a small amount (0.2%) is a heavier isotope, O-18 (there's a tiny amount of O-17 also). Then, most carbon is C-12, but ~1% is C-13 and about one atom of carbon in a trillion is C-14, a radioactive isotope produced mainly by cosmic rays. So while most O2 molecules weigh 32 AMU (atomic mass units) and most CO2 molecules weigh 44 AMU, the weight of stable O2 can range up to 36, and that of stable CO2 can range up to 49, while rare C-14·O2 molecules can weigh between 46 and 50 AMU.

Why should that matter? The proportions of different molecular masses of these two substances can reveal the source of your diet and the air you've been breathing. Similar mass differences in water exist not only because of oxygen isotopes, but also hydrogen isotopes H-2 (deuterium) and H-3 (tritium). Physical processes such as evaporation tend to leave behind heavier molecules, and chemical processes, including photosynthesis in plants, prefer one isotope over another. This preference is not absolute, but it is enough that some kinds of foods have less O-18·O-16 in them compared to others, and so forth.

We also learn that each element connects us to the stars and to all life, each in its own way. Most hydrogen is primeval, created in the Big Bang, but some very small amount arises by spalling from processes such as cosmic ray collisions with atmospheric atoms. No elements heavier than lithium are primeval, but were created in extra-large stars that later exploded as supernovae, scattering them into the universe. So the hydrogen in you is billions of years older than your other elements…although a very few H atoms might be just a few days old! And all that oxygen and CO2 that you've breathed out? Something or someone else (a great many "else's") are breathing it in, at least some of it, right now.

Each chapter of the book discusses primarily one element, or sometimes two. So, while we are sometimes told most life is composed of CHON (carbon, hydrogen, oxygen and nitrogen), the chapter on sodium and potassium reveals why your nerves wouldn't work without them, nor without calcium (the chapter after). Calcium isn't just about bones, and sodium isn't just about food tasting good. They are essential to second-by-second life processes. As it happens, one of the most essential is phosphorus. So much so, that this element may determine just how many humans Earth can support. It is really rather rare for an element that must make up 1% of your body's weight! That is more than ten times its abundance in the Earth's crust in general, but thousands of times as abundant as the 'available P' in the biosphere. Hmmm. I've predicted that coming wars will be over water. Perhaps later wars will be waged for access to phosphorus bearing minerals…if indeed those come later.

Though the book discusses 9 elements (I didn't mention iron above), that leaves a couple dozen "useful" elements in our makeup, so another book is not out of the question. I'd like that. I really enjoyed Your Atomic Self.

Friday, April 24, 2015

Maps are visual thinking

kw: book reviews, nonfiction, maps, mapping, diagrams

For much of my childhood my parents took us on numerous road trips, frequently of the night-on-the-road variety. Dad or Mom would often pick up a current road map of the state or states we were passing through; gas stations used to hand them out free. We wound up with boxes of them. When I was a teen there was a large shed in the back yard we used for various kinds of "club house", including a place for my folk band to practice. We hung up some of the old maps for decoration, and were thinking of papering all its walls with them, but never did so. As a geology student, maps became ever more important to me, and I learned a great variety of concepts I could tag to geography.

Imagine my surprise upon encountering the first map in an "Alternative Atlas", in which the Unites States and some other countries have gone missing! Titled Surrealist Map of the World and attributed to Paul Eluard, I suppose it shows what was important to him in 1929 when the Left everywhere had such hopes for Communism and Socialism (Alaska was part of Russia at the time).

This map is found on page 8 in the introduction to Mapping it Out: An Alternative Atlas of Contemporary Cartographers, edited by Hans Ulrich Obrist. While many of the diagrams in the book, in its near-coffee-table format, are based on geography or some distortion thereof, not all are. However, a great many of the "artistic" items are so abstract they have meaning only for the artist. Thus, I'll do my usual blather about a few that I could at least comprehend.

Here, from page 29, is a political map of the USA by James Croak, showing the relative clout of Senators relative to the population of their home states. Each state has 2 Senators, regardless of population. I detect a somewhat different political agenda, however. Mr. Croak seems to be trying to mobilize the Democrats or even to scare them, by squeezing them into the corners. Why else make Delaware, which has a population no more than double that of Wyoming, appear around 1/100th that state's size? By the rules he set up, it ought to be closer to half the size shown for Wyoming. Also, California and New York, with 70 and 40 times Wyoming's population respectively, should appear as tiny is Delaware is shown. Of course, those are blue states, so it's hard to discern what's really going on. Maybe he factored in the years of experience of the Senators? or their clout on important committees?

Here is another geographical map, also with political intent, that is much better conceived and executed. From page 45, it is an educational diagram by Kai Krause, showing that Africa is a lot larger than most of us realize. Of course, the area of Asia is 50% greater than Africa, but half of that is the frozen wastes of Siberia.

Try this out for your next bar bet: "The land area of Africa is about equal to that of the USA, Europe, China, and India, combined." Be sure to scope out the actual figures beforehand and have them handy! A good wi-fi connection in the bar will also help.

The era of Big Data has enabled scientists and artists and everyone alike to gather and collate and chart almost anything, whether related to geography or on any other basis. I particularly liked a map of the U.S. and nearby parts in North America, created by Aaron Koblin, found on page 110, showing the density of air traffic based on public data on daily flights.

The editor writes that this shows something about working life in America. It also shows how most of the country west of the 97th Meridian is "flyover country". Leave out the big hubs in Denver, Salt Lake City, Phoenix, and Las Vegas, and there are nearly no landings in that half of the country until you get to California.

I sometimes wonder what a map would look like based not in physical distance but on travel time, using the database found in a GPS navigator. Let's gather the parameters for making such a map. I live on a street about 0.4 mile long that connects to a 6-lane road at its west end and a "2-lane blacktop" suburban road at the other, one that is crossed by a road-ditch for rainwater at each intersection. My road and 8 others run east-west between the two. These 9 roads have a speed limit of 25 mph and speed bumps that slow most cars to 20 mph. The road to the east is hard to traverse at greater than 25 mph. The big road to west has a 45 mph speed limit but most traffic goes at least 50 mph. There is also a north-south road that crosses all 9 east-west roads about midway along with stop signs at every intersection, some 2-way, some 4-way. Practical travel along it seldom exceeds 15 mph. The N-S length of the three roads in that direction is about 0.5 mile.

Nest, turn these numbers upside-down, using a unit of tenths of a minute (6 sec) per mile:
  • Big road to the west: 600/50 = 12
  • 2-lane east-side road: 600/25 = 24
  • Road up the middle: 600/15 = 40
  • 9 E-W roads: 600/20 = 30
Those are the numbers to multiply by the length of each road segment. A time map for getting around in this neighborhood would be 6 units high on the left, 12 units high on the right, and a puffy 20 units high down the middle. The right-left size would be 12 units. In this illustration, the upper time map shows an attempt to use straight lines as much as possible. The wiggly sections at top and bottom became necessary when straight lines could no longer connect properly. That gave me an idea, which I sketched out as seen below. I set the middle road a little longer in total extent compared to the one on the right, but used wiggly lines to show that each block is really even longer. They also convey the start-stop feel of that road.

The geographic neighborhood is quite close to being a rectangle, but either of these time maps gives a better feel for what it is like to navigate. With all of this buried in the database of my GPS, it can determine the fastest route between two points. The upper map in particular shows how it is almost equally fast to go from the top center intersection to the bottom center intersection, whether you go "straight down" the middle road, or go first to the highway, then down, then back in! The only wild card is how long it takes to make the two left turns in the latter case. But going the other direction, those are right turns, and the physically longer way is probably the fastest.

In a more conceptual section of the book, some of the map creators brought in more dimensions. This example by Toyo Ito, from page 202, is an attempt to give a feel for the many-layered structure of a city's infrastructure. To me it resembles the solid substrate of bone, with its many voids in which separate systems for blood, lymph and nerves can pass with minimal interference. Whichever metaphor pleases you, it is a powerful concept.

If we generalize the concept "dimension" into the physicist's term "degree of freedom", we can use conceptual maps to show several variables together. A favorite example of mine is the chromaticity diagram, which represents human color vision, at least for most folks. Various kinds of color blindness require very different charts, as do the rare cases of female tetrachromaticity (4-color vision).

The chromaticity diagram shows "color coordinates" of the colors a normal human eye can see. The outer edge of the horseshoe shape follows the pure, or saturated, colors of the rainbow. The numbers around the shape are the wavelength in nanometers (nm). All colors inside the shape, and along the flat base, are produced by mixing two or more spectral colors.

The creator of this version of the diagram has superimposed generic color names on various regions of the color space. The central sort-of-oval part encompasses colors typically called "white" and "off-white".

The curved line from near the "600" point on the edge at the right, through the middle, is called the "black body locus", and represents the colors of anything hot enough to glow. Point "A" near the "yellow" area is the nearly-white color of an incandescent light bulb. Letters "B" through "E" show other standard light sources originally produced by filtering out some of the red and orange colors of an incandescent lamp. Black body colors closely match the colors of stars of different temperatures. The noontime Sun has a color at point "D". Cooler stars have redder colors toward the right, and hotter stars are bluer. The tip of the black body locus is the limit of incandescent blueness for a nearly infinitely hot star.

Thus, I would generalize: any diagram is a map of some kind. The book helps to broaden our understanding of mapping from a more-or-less explicit exercise, to a conceptual and recreational activity in which we all engage. Though "cartography" as a discipline began with geography, we can also map not only color but all the senses, plus relationships, processes, functional planning and, really, anything we can think of. To Think is to Map.

Sunday, April 19, 2015

Nearly zero times nearly infinity

kw: book reviews, nonfiction, biology, evolution, biogeography

I learned a new word: vicariance. Although the related word vicarious means "on behalf of another" or even "second hand", the emphasis on this word's coinage is the separation of a biological population into two or more parts by some change in environment, leading to new species. The principal connotation, however, is on the "second hand" experience of members of the population that are thus separated from and even carried away from their fellows and thus physically prevented from breeding across the new barrier. And, AND, the principal emphasis of "vicariance biogeography" has been upon describing the distributions of related species and genera in terms of relict populations from the separation of continents that began about 200 million years ago with the breakup of Pangaea and then Gondwana.

Pangaea was the most recent supercontinent (there have been at least 5 over some 3 billion years or so), comprising just about all the land surface of Earth, that formed some 300 million years ago when earlier, separated continents were driven together. It first split in two, forming Laurasia in the north and Gondwana in the south, then these each split further. The rift that became the Atlantic Ocean began forming in the north about 140 ma ("ma" is the abbreviation for "million years ago"), but the southern half did not begin to open until something like 70 ma or so. The closest distance across the Atlantic is currently 1,800 miles (2,900 km), but it was half that roughly 35 ma, a fact to which we will return.

I was a geology undergraduate in the 1960s, just as the old "shrunken apple" explanation of mountain building I'd learned as a child was being thoroughly replaced by the new paradigm of plate tectonics. It was an exciting time to learn geology. I had the most interest in paleontology (fossils), and much was made of the correspondences of late Paleozoic and early Cenozoic fossils across the Atlantic between the facing continents of South America and Africa. This naturally led the few biogeographers of the time to describe the distribution of nearly all living things as being a consequence of continental motions.

As described in The Monkey's Journey: How Improbable Journeys Shaped the History of Life, by Alan de Queiroz, for some this concept became dogma. "Nearly all" became "all" in their minds. When new evidence showed that continental breakups do not explain everything about the distribution of species, they were, and in some cases still are, unable to assimilate the new information.

As it happens, the last rift in Gondwana opened about the time of the dinosaurs' demise; it is now obligatory to add, "except some of the flying dinosaurs, that we now call birds". To the point: major speciation by continental separations ended about 70 ma. Lesser events, such as desertification of formerly temperate regions, re-routing of rivers, or mountain chain development, must be called upon for any later splitting of gene pools due to vicariance. Of course, strictly speaking, vicariance refers to anything that divides a population, even the removal of several members to a different island or continent, but "vicariance biogeography" discounts "dispersal" mechanisms.

The Monkey's Journey describes the rise and fall of vicariance biogeography as the principal theory of species distributions. Prior to the new paradigm of plate tectonics, several competing theories about the dispersal of plants and animals competed for academic attention. Charles Darwin had done much work to understand how chance dispersal across oceans and other significant barriers could take place. Plate tectonic knowledge was more than a century in his future, and he didn't want to just posit "land bridges" rising and falling wherever it would be convenient. So then, just how did some similar kinds of living things come to populate far-flung continents? It is easy to see that, once continental motions were known, they were grasped upon like a holy grail, to explain absolutely everything about both geography and biogeography.

Of course, that "bio-" part is a problem. Rocks can't walk, swim, burrow, fly, or crawl. Animals can, and plant seeds and even certain plants can either do some of these things, or be carried along when animals do so. So it stands to reason that purely mechanical motions of continents and other landforms cannot explain everything when it comes to creatures with volition.

By the 1980s, significant evidence had accumulated to call into question many "of course" assumptions of the vicariance crowd (nearly all the biogeographers). Hawaii is a case in point. None of the Hawaiian islands was ever even close to any continent. Neither were any of their precursors, including the Emperor seamounts that used to be islands. Every species on any island of Hawaii that was not brought there by the Polynesians or later humans somehow crossed a few hundred miles of ocean, or is descended from a species that did so. The Galapagos islands are similar: perpetually oceanic. There are other examples. Pangaea didn't include absolutely all the land on Earth.

DNA sequencing, begun in the late 1980s, seemed to provide a way of confirming the various species-splitting events, and it was expected to confirm vicariance theories. However, the early "molecular clock" techniques were a bit of a joke. The various "clocks" were notoriously inaccurate and unsteady. Depending on the bit of DNA used, the "tick" could vary over a range of thousands to one. But time marches on, and scientific progress with it. Molecular biochemists have learned a few things in the 30+ years since, including ensemble methods to have a group of "molecular clocks" correct for each others' instabilities. Nobody can yet pin down any event millions of years in the past to the nearest hundred or thousand years, but the difference between 20 million and 200 million years is readily discernible, and that between 20 and 50 million can be cleanly determined.

Considering just animals, island ecosystems typically show a range of species diversity that matches ease of travel by different kinds of animals: many kinds of birds and flying insects, fewer kinds of endemic mammals and reptiles, and very few amphibians or even none. But there are some astonishing cases of animals you'd never expect could cross an ocean, living on oceanic islands. The most astonishing case is that of the monkeys, but this is not about islands. Unless you recall that, until 3 ma, South America was an island, just a very big one, and it became an island nearly 70 ma.

Three million years ago, the Atlantic Ocean was almost as wide as it is today, and the Pacific was much, much wider than that. So vicariance biogeographers have been very diligent to find a way to get primates between Africa and South America, without leaving a single fossil in North America, at some time before 70 ma. The plausible explanation was that monkeys could simply walk west out of future Africa to future South America. The trouble came after molecular dating showed that New World monkeys and Old World monkeys and apes did not split from one another until some time between 20 and 40 ma, with the most likely date close to 35 ma.

At that time, the closest bit of African land was 900 miles (more than 1,400 km) from the closest bit of South American land. So the new explanation came to this: posit land bridge (a proto-Panama) about that time, and some similar connection between northern Africa or Europe and North America, plus a long period of warming so monkeys would be willing to go to, say, Spain, to get to America. Then somehow they walked south to South America, leaving not a single monkey fossil behind. Considering the thousands of fossils of Eocene and Miocene horses, tapirs, and sloths found throughout North America, the absence of monkey fossils is telling. Yes, "absence of evidence is not evidence of absence", but such a case as this is pretty close, pretty close. Monkey fossils, later than 35 ma, are abundant throughout South America…

So somehow, a major "floating island" sort of raft got ejected by an African river and made its way to South America before all the animals on it died. Every chapter of the book ends with an anecdote, and here is a relevant one from the end of chapter 4:
In July 1892, a natural floating island was spotted off the northeastern US coast, at about the latitude of Philadelphia and some 300 miles from the nearest land. The island was roughly 9,000 square feet in area, contained living trees 30 feet tall, and is said to have been visible from 7 miles away. The same island was again seen in September, by which time the Gulf Stream had pushed it more than 1,200 miles northeast of its previous position. (Powers, Sidney, 1911, Floating Islands, Popular Science Monthly 79, 313-307)
Let's see, 1,200 miles in two months. Had a similar island become caught up in the equatorial current between Africa and Brazil after being ejected by a proto-Senegal River, it might have made the crossing in 5-6 weeks. It would have brought, not just monkeys, but dozens or hundreds of species of all kinds, plant and animal. Not all would survive as colonists, but some would. It only had to happen once, once over a span of millions of years.

The vicariance diehards pooh-pooh such explanations, as much too unlikely. Well, so was the origin of life. But that also had to happen only once, and considering how early it happened, it was only "moderately unlikely". So was this. People tend to think of things that are very unlikely as "miracles" if they occur anyway. The "once in a million chance" is a venerable staple of storytelling, and the classic example is a hole-in-one in golf. Few golfers have seen one, fewer still have done one. Jack Nicklaus did one a couple of weeks ago, at age 75. Of course, he has done 20 of them, in competition, but then, he has probably hit several million drives that were not holes-in-one! But even if the monkey-bearing raft is not just one in a million, but one in a billion, a lot can happen in the 70 million years that South America was an island.

A major point of the book is, that the biota of nearly everywhere is much more a product of long-distance dispersals across all kinds of barriers, more than we had thought of. So much so that relict Gondwanan species pairs, or genus pairs, are actually rather hard to find! But that's not the only point. The author brings to life for us many of the principal players in biogeography, details the steps of study and reasoning that were key to the shifting winds of understanding over the century-and-a-half that have elapsed since Darwin released The Origin of Species in which he also discussed species dispersal mechanisms. "Dispersalism" is proclaimed as the resulting paradigm. Of course, there are a few pesky Gondwana relicts around, and other evidence that dispersal on all scales, over all time scales, has gone on. Scarce, chance travels by unlikely travelers have led to Earth's lands becoming a story of "everybody came from everywhere". The proper answer to any question, "Which way did these plants and animals get here" is, "All of the above". Leave dogma to the world religions where it belongs. Science is about discovering what is, and to some extent, how it came to be, based on evidence.

So THE major point of the book, that bears repeating endlessly (especially to certain mis-named "scientists" I know) is this: Evidence must drive theory, not the other way around.