Jacob A Tennessen Profile picture
Scientist errant. Genetics, evolution, whimsy, awe. @HarvardChanSPH & @broadinstitute. Responsible for @biolojical & https://t.co/PF78hV9CYH he or they
Carol Morton Profile picture 1 added to My Authors
Jan 22, 2022 6 tweets 1 min read
Apropos of nothing in particular, pondering: mainstream academics aren't great at doing engaging outreach on human biology, in part because it's potentially controversial and thus scary. But this leaves an empty niche for rogue opportunists with an agenda. If someone is curious about human population structure, the biology of human sexuality, the genetics of intelligence, etc., they should be able to find clear and authoritative info on the websites of universities and scientific societies. Instead they mostly find alt-right blogs.
Aug 28, 2018 8 tweets 4 min read
New paper! A sex-determining DNA sequence in wild strawberries has repeatedly jumped to new genomic locations, leading to increasingly differentiated sex chromosomes. Here’s the summary (thread).
journals.plos.org/plosbiology/ar… Some wild strawberry species have distinct sexes (male left, female right), but their recent ancestors and close relatives (including the🍓we eat) do not. This setup lets us study how and why a perfectly good hermaphrodite evolves to stop making both gametes. Photos: Gerry Carr.
Jul 3, 2018 5 tweets 1 min read
It is not a scientific fact that “life begins at conception.” However, genetics is often (wrongly) invoked to support pro-life views. In light of the increasingly tenuous fate of Roe v. Wade, biologists need to keep addressing this misunderstanding. [thread] DNA does not define a life. An embryo has a different genome than the body carrying it. So do sperm, eggs, and white blood cells. So do the remaining fetal cells in a mother post-birth, which incorporate into her organs. Twins have the same DNA. My future corpse will have my DNA.
Dec 26, 2017 9 tweets 3 min read
This tweet went viral over the weekend, and I got a flood of questions about sex, gender, and genetics. I wanted to wait until after Christmas to delve into addressing them. So let’s go.
There are two human sex chromosomes, X and Y. Most humans either have two Xs (XX) or one of each (XY). But you can’t extrapolate the number of human genders from that fact, for three main reasons: