Did you know that at your Toronto Zoo, we can determine if a rattlesnake is male or female using just its skin shed? 🐍 On this #NationalDNADay, we are highlighting work the Reproductive Science team has undertaken with the threatened Eastern massasauga rattlesnake. As a reptile, rattlesnakes can take several years to mature and lack external reproductive structures, making factors like accurately determining sex challenging. Unlike humans and other mammals that have XX and XY sex chromosomes, many snake species have a ZZ and ZW sex chromosome system instead. This means male rattlesnakes (ZZ) have more Z chromosome DNA compared to females (ZW). Researchers at your Toronto Zoo have tapped into this DNA difference between male and female eastern massasauga rattlesnakes to help determine the sex of individuals on an accelerated timeline. Instead of having to wait years for snakes to sexually mature, the skin that is naturally shed from individuals can be non-invasively collected at...