- Feathers, Scales, and Hair are all related
No wonder dinosaurs learned how to fly! Scales, feathers, and hair are all related! They all come from a common ancestor from 320 million years ago. A group from Geneva published a paper in Science Advances, suggesting that the reptilian ancestor was covered with scales that came from placodes. Placodes are areas of thick tissue that happen during embryo development. These areas can result in feathers, hair follicles, skin around the nose, or specific neurons.
Placodes have been found in mammal and bird embryos but never on reptiles. The group was actually looking for a gene that resulted on hairless bearded dragons and identified a specific gene, EDA. Interestingly, when this gene is modified in humans, hair follicles, sweat glands and teeth don’t develop properly. This gave the group an idea that reptiles do have placodes- which they found in snakes, crocodiles, and lizards!
This new finding enhances our understanding of evolution,uniting mammals, birds, and reptiles together.
- Overweight fathers affect their daughter’s breast tissue development… in mice
Daughters of overweight fathers have increased mammary tumors and delayed mammary development in mice. A study found that male mice that gained weight had a change in the germline causing a genetic change in the paternal sperm.
This is the first study of its kind since most papers focus on the effect of maternal weight gain on daughters. The study in mice further found that if a father is overweight, the daughter will be overweight at birth and throughout development. The group hopes to continue the study with human daughters and fathers to expand our knowledge. So next time you’re thinking of eating that extra donut, think about your genetic makeup!
Michelle Rubin (Editor-in-Chief)
Michelle is a fourth year biomedical PhD student. She is extremely interested in science policy and hope to pursue that after her studies. Let her know what you think of the blog on twitter! @michellejrubin.