Who is Nettie Stevens? You may have noticed that today’s Google Doodle shows a woman scientist in a laboratory looking in an old-fashioned microscope. The slide she is looking at contains an X and a Y chromosome, the chromosomes that determine whether a newborn will be a girl or a boy.
— marsha walton (@marshawalton) July 7, 2016
According to Nature, Nettie Stevens discovered that it is the man who is responsible for whether or not a baby is a boy or a girl. She found evidence for the presence of what would come to be called the X chromosome, that is found in both men and women, and the Y chromosome, that is found only in men. The female, therefore, contributes only X chromosomes to the fertilized egg that will become a baby. The sperm contributes either an X or a Y chromosome. If the fetus is XX, the baby will be a girl; if it is XY, the baby will be a boy. And it is the father, therefore, who can be said to be accountable for the sex of his infant.
If you don’t know who Nettie Stevens is or the impact she had on science, you should be interested in the fact that her discovery turned everything known until then about the baby’s gender on its head. Women had traditionally been blamed when they had daughters instead of sons, especially the first-born child. Sons are important for continuation of the family name and, for royalty, for the right to pass on the crown to their own offspring.
— ScienceAlert (@ScienceAlert) July 7, 2016
Nettie Stevens was born 155 years ago, in Cavendish, Vermont. According to the Independent, she published about 40 academic papers but did not gain the recognition she would have had she been a man. In fact, it was a man, Edmund Wilson of Columbia University, who was credited with the discovery. Others suggest that Thomas Morgan made the discovery, but usually Wilson gets the credit.
Living Legacies, an online journal recording the accomplishments of Columbia University faculty, discusses the fact that Wilson and a number of other researchers were simultaneously exploring how offspring gender is determined. The author states that Wilson submitted his work to The Journal of Experimental Zoology about ten days before Stevens did and yet his study was published a full two months before hers. Is this a case of giving the man the upper hand? By giving Wilson’s paper a two-month lead over Stevens’ paper, were they unable to accept the possibility that a woman had made a great discovery?
Vox reports that it was Nettie Stevens’ conclusions that stood the test of time. It appears that Wilson still believed that environmental conditions affected the sex of the unborn child. Stevens concluded that it was the chromosomes alone that decided whether the infant would be male or female. It seems that Wilson was still unwilling to accept male responsibility for the sex of their children.
Nettie Stevens’ life story has an important lesson for women — and probably not just for women. The Nature article describes the times in which she was born and grew up. In the late 1800’s women were not expected to work outside the home. And if they did work, they would aspire only to secretarial, nursing or teaching professions. Nettie, however, wanted more. She did start off as a teacher, but only as a way to earn enough money to put herself through university.
Stevens would work for a while to save up enough money for the next stage of her education, and then return to work to earn more. Finally, at the age of 39, she achieved her goal and became a research scientist. Over the next 11 years, she was able to write 40 scientific papers and ultimately make the discovery of sex chromosomes that would change our understanding of infant gender and also lead to the discovering how certain medical conditions are passed on by mothers to sons but not to daughters.
Nettie Stevens’ determination against all odds should be an inspiration to all of us.
I've never heard of Nettie Stevens before today. Thank you Google Doodle for giving her appropriate attention and respect.— Piper Huguley (@piperhuguley) July 7, 2016
Stevens died of cancer at the age of 50 just as she finally attained full professor status.
[Image via The Incubator/Wikimedia Commons]