If you’ve gone to the Google homepage at some point today, you’ll have noticed the above

If you’ve gone to the Google homepage at some point today, you’ll have noticed the above doodle of Nettie Stevens. Today (July 7, 2016) marks the 155th birthday of Nettie Stevens, a woman who made major contributions in the discovery of the X and Y chromosomes. Though the work is frequently attributed to her male colleagues Thomas Hunt Morgan and Edmund Beecher Wilson, many argue that more credit should be given to this pioneering female biologist. Born in Vermont in 1861, Nettie Stevens worked as a teacher of physiology and zoology before saving enough money to enroll at Stanford at age 35. Stevens then completed her PhD work at Bryn Mawr, where she became a student of T. H. Morgan and E. B. Wilson. By the time she had finished her PhD, she had already published nine papers, and was soon after given an award of $1,000. With this grant, Stevens began her work on chromosomes.In the 1890s, Stevens began studying mealworm beetles, and noticed that the females had 20 chromosomes of the same size, whereas males had 19 chromosomes of the same size and one smaller one. Stevens correctly theorized that the size of this final chromosome determines the sex of an organism. While Wilson came to similar results at the time, it is argued that Stevens made original contributions that should not be overlooked. Through careful dating of their published work and correspondence, it is clear that many of the important ideas of sex inheritance should be attributed to Stevens.Though Wilson got the credit for so much of her research, before her death, she had the honor of being listed among 1,000 leading American “men of science”.Read more about Nettie at Genes to Genomes, read about the undervaluing of her contributions at Vox, or learn some fun facts about her at The Independent.Happy birthday, Nettie Stevens! -- source link

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