The Wild Science of Water Bears

Huge Discoveries Could Come From Tiny Tardigrades.

- Kathiann M. Kowalski

Tardigrades are often called water bears, but they’re not bears at all. They’re invertebrates, meaning they have no backbone. And they’re so small you need a microscope to see them. Yet, these tiny creatures are so tough that scientists are impressed—and eager to learn more.

Found in Water Everywhere

Some water bears live in oceans and seas. Some live in fresh water. Still others thrive in water on tree mosses or in damp soil.

So far, there are more than 1,000 known species of tardigrades. As a college student, Alex Young worked on a summer project with William Miller and other biologists in Kansas. Team members collected moss and lichen from trees. At a lab, they used dissecting microscopes to examine the samples for tardigrades. Research helped them classify what they found.

Young found a population of tardigrades that did not fit any existing descriptions. More research followed. “It was a long, involved process,” he says. When the team was ready to describe and name this new species, “it was definitely exhilarating,” Young says. The team published its discovery in 2016.

Miller, who teaches at Baker University in Kansas, has been involved in finding more than a dozen new species of water bears. Tardigrades are found on every continent, including Antarctica. But no clear patterns exist for the numbers or diversity of species at different places. As an ecologist, Miller says that’s “sort of unsettling.”

Pudgy Little Animals