Every beehive has a single queen bee, and the queen in hive #1 is called Nettie. She is named after Nettie Stevens, who was a geneticist, and who first observed the Y chromosome and identified it as being the one responsible for male sex determination.
Nettie Stevens was born in Vermont in 1861, and the family moved to Massachusetts when she was 2 years old. She attended Westford Academy, Westfield Normal School (now Westfield State University) and Stanford University, where she studied for her BA and MA in biology. She then began graduate work in physiology and histology. Following this, Nettie enrolled in Bryn Mawr College to undertake a PhD in cytology. Her doctoral studies encompassed a number of areas, including the development of sperm and eggs, and the germ cells of insects.
Nettie was awarded her PhD in 1903, and remained at Bryn Mawr first as a research fellow in biology, then a reader in experimental morphology. In 1904-1905, she spent a year as a post-doctoral research assistant at the Carnegie Institute of Washington, where she received a grant to undertake research on heredity, including sex determination, based on Mendel's theories of inheritance. Nettie began by studying the germ cells of aphids, to try to identify possible differences in male and female chromosomes.
In 1905 Nettie observed that the male chromosome set of Tenebrio molitor (the yellow mealworm beetle), consisting of 20 chromosomes (in 10 pairs), had one unusually small chromosome. She correctly identified this as being the chromosome that determines sex, and published her results in a paper titled Studies in Spermatogenesis. Nettie further noted that this small chromosome was always paired with a larger one, and that an egg fertilised by a sperm that carries the small chromosome becomes a male while an egg fertilised by a sperm with the larger chromosome becomes female. She then studied other organisms, including aphids, mealworms, beetles, and flies, and found that they used the same large-large / large-small chromosome parings to determine sex. We now refer to these pairings as XX and XY.
Nettie became ill with breast cancer at the age of 50. She was offered the position of research professor at Bryn Mawr College, but was unable to accept the offer due to her ill health. She died on May 4, 1912. Despite her short life, she published around 40 research papers and made one of the great discoveries of modern biology.
You can find out more about Nettie Stevens here:
https://en.wikipedia.org/wiki/Nettie_Stevens
Here is a photograph of her namesake, queen Nettie:
Science bonus!
If you're a bit of a geek (and regular readers will know this is a pro-geek zone), you can read Nettie's original Studies in Spermatogenesis paper online. Here's the screen-reader friendly version, courtesy of Project Gutenberg:
https://www.gutenberg.org/ebooks/31545.html.images
It's also available in other formats - here's a list:
https://www.gutenberg.org/ebooks/31545
And here, at the Internet Archive, is a scan of the original:
https://archive.org/details/studiesinspermat01stevrich/page/n8/mode/1up?view=theater
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