Mary Treat (1830-1923) was a prolific scientific writer who earned a reputation as “the world’s most famous and industrious woman naturalist” at a time when few women were professionally engaged in biology.
The daughter of a minister, Treat attended a private girls’ academy early in life. Such academies, or “seminaries,” were an answer to the contemporary lack of rigorous female education in the United States at the time; and in addition to ladies’ finishing courses, the academies trained students like Treat in the sciences and humanities. Early encouragement of this sort was influential for Treat. But it was her relocation to the intellectual commune of Vineland, New Jersey in her adulthood that her interest in daily observation and intellectual exchange flourished.
It was in Vineland that Treat launched her scientific career in 1869, at the age of 39. Here Treat began observing local insect life in earnest, making daily and detailed observations about particular species, collecting specimens, and writing about her findings. Taking her pursuit of science to a vocational level by 1871, she entered correspondence with professional scientists Asa Gray and Charles Sargent at Harvard University. While both contacted her as a source for specimens and requested her assistance in identifying samples of their own, Gray in particular also urged Treat to extend her interactions with the scientific community by publishing her own work and by reaching out to share work with evolutionary biologist Charles Darwin.
Treat became a prolific and successful writer, contributing alike to professional journals such as The American Naturalist and to popular magazines like Harper’s. During her lifetime, Treat was praised by male scientist for eschewing the stereotype of the sentimental female nature writer, instead favoring logical observation and use of the scientific method. Yet her conversational tone and her desire to open science to all interested parties made her a favorite among women non-specialists as well. Inviting in female readers, Treat encouraged them to read, understand, and pursue their own into scientific inquiries. Her publications became a means of financial support that afforded her independence following her divorce. Ultimately, she would author 5 books and over 70 scientific articles.
Among Treat’s most important published works is the 1885 book “Home Studies in Nature,” wherein Treat considered carnivorous insect life and its diverse evolutions. In it, readers can witness her insertion of wry wit into scientific study, managing to engage readers in the drama of entomology as well as inviting them to participate in analysis rather than passively read her observations:
“I have devoted much time to a class of plants that seem to have reversed the regular order of nature, and, like avengers of their kingdom, have turned upon animals… Whether the plants are really hungry and entrap the animals for food, or whether it is only an example of the wanton destructiveness of nature I leave the reader to judge.”
Among her contemporaries, Treat gained notoriety as a rigorous editor committed to correct observation, illustration, and reporting. Surviving letters from her long-term correspondences with Gray and Darwin reveal that Treat early on became a collaborator and possible competitor to these scientists.
As early as 1871 Asa Gray wrote in one letter to Treat about their future exchange of research:
“I fancy you might use anything I write about [these species] in your articles – I am glad you write…I hope you will equally allow me to use your remarks.”
Within three years, Gray wrote another letter thanking Treat for samples and observations, remarking
“you write to Darwin-& to me about it…[but] better introduce the date at which … you first found the idea.”
Gray reveals his confidence that Treat could potentially beat him or Darwin on the issue, and that all three scientists need to maintain records of their progress to ensure that credit is given properly for first discoveries. Notably, Treat directly commented on and corrected Darwin’s work. In a letter of 1875, Darwin notably comments to Treat, “I have read your article with the greatest interest. It certainly appears from your excellent observations that the valve was sensitive. … It is pretty clear I am quite wrong about the head acting like a wedge. The indraught of the living larva is astonishing.”
Ignoring details of gender, Darwin soon after acknowledges Treat’s contributions in his own book Insectivorous Plants (1875):
“Mrs. Treat of New Jersey has been more successful than any other observer.”
To date, no major biographies of Mary Treat exist. Yet her legacy lives on through her correspondence and publications.
Darwin Correspondence Project, University of Cambridge. Asa Gray Collection, Harvard University. Caruso and Kohn, Bibliographical Dictionary of Women in Science, 2003. Gianquitto, American Women and the Scientific Study of the Natural World, p.136-76. MacLean, “History of American Women”(8.17.2014). Treat, Home Studies in Nature (1885). Darwin, “Insectivorous Plants” (1875).