Tardigrades aren’t champion gene swappers after all
Study dispels claims of extreme DNA borrowing and moves the bizarre creatures on the tree of life
EXTREME SURVIVALIST Genetic analysis of tardigrades like this Ramazzottius varieornatus shown in a scanning electron micrograph are revealing what makes the tough little creatures tick.
K. Arakawa and H. Higashiyama
A peek at tardigrades' genetic diaries may dispel a rumor about an amazing feat the tiny creatures were supposed to perform: borrowing large numbers of genes from other organisms.
Tardigrades — also known as water bears and moss piglets — hardly ever borrow DNA from other creatures, researchers report July 27 in PLOS Biology.
New analyses of DNA from two species of water bear, Hypsibius dujardini and Ramazzottius varieornatus, also reveal some of the extreme survival strategies that make the creatures so tough, such as how they produce proteins that allow them to dry out. Dry tardigrades can famously survive extreme temperatures, being bombarded with radiation and even a trip to the vacuum of space. What’s more, some assertions in the study may even reignite debate about tardigrades’ proper place in the tree of life.
These glimpses of tardigrade biology
