Despite their tiny stature and their adorable nicknames—moss piglets, water bears—the tenacious tardigrade has some tremendous capabilities. Well-known for being one of the hardiest-known forms of life, tardigrates can survive desiccation, deadly radiation, and even the vacuum of space. Now researchers may finally be starting to tease out the genetic basis of tardigrade superpowers.
In 2015, a study published in the Proceedings of the National Academy of Sciences, suggested that some of their superpowers could come from an another oddball accomplishment of the microscopic creature: DNA theft. The researchers sequenced a tardigrade species’ genome and found that roughly one-sixth of its DNA (around 6,600 genes) appeared to come from other organisms, mainly bacteria. These sections of DNA were thought to be picked up through the process of so-called horizontal gene transfers, which is a common in bacteria and other microbes (scientists have only recently discovered some animals can also do this).
“If they can acquire DNA from organisms already living in stressful environments, they may be able to pick up some of the same tricks,” researcher Thomas Boothby, a Life Sciences postdoctoral fellow at the University of North Carolina, Chapel Hill, told Smithsonian.com in 2015.
But just a week after it was published, the study faced steep opposition. Another group of tardigrade researchers claimed that much of the supposedly “stolen” DNA likely came from contamination of the samples from bacteria that lived alongside the tardigrades. “There is no way, biologically, these can be part of the same genome,” geneticist Mark Blaxter told Ed Yong of the Atlantic in 2015.