A nearly-erased legacy

 kw: book reviews, nonfiction, science, scientists, entomologists, botanists, female scientists

The Hessian fly or Barley midge, Mayetolia destructor (former genus name Cecidomyia) is the most destructive pest of wheat plants. Barely exceeding 3mm in length, a female such as the one shown can lay 300 or more eggs in her adult life span of 2 days. The larvae eat into stems and prevent the plant from reproducing.

During a huge outbreak of the pests in 1836, entomologist Margaretta Morris studied these flies intensively. She noted that most Hessian fly females laid eggs on the stems, while others laid eggs in the culms (where the leaves met the stems).

Considering that there might be two species of near-identical appearance, she collected culms with egg masses and raised them under a bell jar in her study room. She documented the lifestyle, noting how it differed from the lifestyle of the "traditional" Hessian fly (already well known for a generation or more). She described the new species as Cecidomyia culmiculo and sent the description and numerous specimens, including all stages of the life cycle, to the Academy of Natural Sciences in Philadelphia. There they were ignored, and over time the specimens were destroyed by "cabinet pests", the bane of every insect collector who doesn't keep specimens in cedar boxes or in sealed trays with moth balls. To this day, the species goes unrecognized, being grouped with C. destructor as a variation; after all, economic entomologists reason, the same pesticides kill both species/varieties, so there is little incentive for a still-male-dominated discipline to validate a woman's scientific work.

To compound the slight, Miss Morris had found that the 17-year cicadas of what is now called Brood X (10), which erupted in the Philadelphia area in 1834, contained two populations of differing sizes, which she suspected might be two species. This photo compares a periodical cicada on the left with a larger annual cicada, which is green with brown eyes, rather than black with red eyes. The periodical cicadas were initially thought to range in size from 18-38mm, whereas the annual cicada is 40-45mm. She concluded that the "dwarf cicada" was 18-26mm, while the other was 30-38mm.

She corresponded about the phenomenon with a number of scientists, but she was focused more on another matter, that cicada nymphs were ruining fruit crops, particularly of apples and pears. She hosted visitation by numerous scientists to her garden, where her groundskeeper would dig up roots from an apple or pear tree, so they could see the nymphs lined up by the dozens, sucking sap from the roots. She invented a method of root pruning plus fertilization and mulching, to cut off the food supply of the nymphs and strengthen the tree, a method that is still the most effective. Her neglect proved nearly fatal to her legacy as a scientist. Entomologist James C. Fisher named the dwarf cicada Cicada cassini after his friend John Cassin in 1852; it is now known as Magicicada cassini.

It required much detective work and a few lucky breaks for Catherine McNeur to winkle out these facts and others about Margaretta Morris and her sister Elizabeth Morris, a botanist. She has documented the lives of these remarkable sisters in Mischievous Creatures: The Forgotten Sisters Who Transformed Early American Science. It is a big book, eminently readable.

Both women had loved natural science since they were little, and they became prominent scientists in an era of pervasive misogyny. They did indeed transform science in the first half of the Nineteenth Century, firstly by diligent and extremely thorough study and work—which family wealth enabled—and by equally diligent correspondence with numerous scientists and collectors. Their studious care for correspondence networks had a political undercurrent: they knew they needed allies, allies, allies, in their fields of study and related fields. They befriended scientists, sharing and trading specimens and ideas. They hosted many, and some became lifelong friends and supporters. They held demonstrations of their ideas, such as the "cicada digging" parties mentioned above. Later in life their correspondence was equally in support of younger, up-coming scientists, particularly young women.

Ms McNeur notes frequently how a number of male scientists, who might be quite friendly early on as they built their careers, became more distant and abrupt in their correspondence as they became prominent, taking the women for granted as "helpful collectors" but little else. Some men were openly hostile, and the book details a couple of battles-royal engaged in (via letter) by Margaretta, in which the men were at least abashed if not distinctly disproven. One scientist, to his credit, if belatedly, came to respect her and promote her after about a decade.

Elizabeth, the elder by two years, lived from 1795-1865. She was less assertive than Margaretta, but in the end, a trace of her legacy remains in the public record. Here I provide an illustration with its caption. I trust that Trinity College Dublin still retains the specimen named for her. The online biological database WoRMS (World Register of Marine Species) calls the status of the species "uncertain" and its Original Description "not documented". Perhaps someone in Dublin can clear this up! 

The Cladophora seaweeds are very common, bright green, and some are pests. This one from an estuary near Delaware Bay is more of an entangle-your-feet-as-you-wade alga.

The last chapter of the book, "Forgetting", is sad indeed. Step by step, perpetrated by generations of thoughtless and ambitious scientists, the Morris sisters' work was almost entirely erased from the public record. Much of the material used by the book's author was found, sometimes by happenstance, in private collections of letters and other documents. 

While misogyny is not dead in America, or in the West generally, it is much less pervasive than before. But it is not stamped out. In fact, the odd phenomenon of the 2020's titled "Wokeness" is increasingly misogynist, favoring false females over the real article!

In my experience, scientists who are insecure in their standing are more prone to oppose and marginalize others, particularly women (if they themselves are men); such persons deserve their obscurity. Those of prominence who are still insecure are shameful.

Mischievous Creatures is excellently researched and written, full of information and stories of these two remarkable women. I looked for the phrase "mischievous creatures" as I read, but didn't find it (maybe I read some parts too fast), so I don't know if the author intended to refer to the Morris sisters thus, or something else. This book is a must-read for all who are interested in the history of science, particularly in early America.