Chemist Breaks Down How At-Home Covid Tests Work

Over the past two years, you’ve likely taken a Covid rapid antigen test. A unique, biochemical reaction involving saline, tiny particles of gold, and paper with antibodies, is helping to give us quick and relatively accurate results. Dr. Kate Biberdorf, a chemist and author, explains the chemical process of the at-home tests (while taking one!) […]



Why Cat Eyes Have Vertical Pupils

Peering into the eyes of different animals, you’ll see some extraordinarily shaped pupils. House cats, for one, are twilight hunters with vertically elongated pupils. Many grazing animals, like goats, have rectangular pupils. Other animals have crescent- or heart-shaped pupils. So, what’s going on? Why are there so many different pupil shapes? Emma Bryce digs into […]