August 25, 2014

Water Bears: Small and Mighty

Photo of a tardigrade by Willow Gabriel, courtesy of
Goldstein Lab, UNC Chapel Hill
The tardigrade was not a well-known animal outside of the scientific community until recently. When tiny tardigrades were featured in the remake of Cosmos, however, they grabbed public attention and haven't let go.

These tough little critters are more commonly known as water bears. They aren't actually bears. Water bears are classified as extremophiles, or animals that can survive conditions that would kill most other life on Earth. They are tough enough to survive freezing, boiling, radiation, and completely drying out (desiccation). They can even survive in the cold vacuum of outer space.

August 16, 2014

Is the platypus a mammal, or what?

Photo courtesy of the State of New South Wales, Office of
Environment and Heritage
Yes, the platypus is a mammal. It and the echidna are the only mammals on
earth today that lay eggs instead of giving birth to live young. However, both animals have fur and produce milk with their mammary glands, which are the hallmarks of mammals. The female platypus lacks nipples, so she excretes milk through her skin. Wild platypus are only found in Australia. The bizarre appearance of this egg-laying, duck-billed mammal baffled naturalists when it was first discovered. Many thought the animal was an elaborate hoax-- the back end of a beaver glued to the front end of a duck. However, the platypus is a real animal. It is one of the few venomous mammals, as the male Platypus has a spur on the hind foot which delivers a poison capable of causing severe pain to humans. The unique features of the Platypus make it an important subject in the study of evolutionary biology and a recognizable and iconic symbol of Australia. It has appeared as a mascot at national events and is featured on the back side of the Australian 20 cent coin.