Unpublished sequence reveals how little tardigrades walk | Science and Ecology | DW

Resistance to bullet impact, resistance without water, and surviving gravitational changes in space are some of the characteristics that make tardigrades –Hypsibius style– Impressive, rare and interesting objects for scientists.

The so-called water bears were discovered in 1773 by a German zoologist. Since then, scientists have analyzed their behavior and published microscopic images of their appearance.

However, despite having four pairs of visible legs with claws on their limbs, no one had ever seen them walk. Recently, researchers at Rockefeller University documented for the first time how these tiny creatures move.

They walk like insects and arthropods

According to experts’ observations Published in the scientific journal Proceedings of the National Academy of Sciences (PNAS), water bears have an extraordinary ability to walk similar to insects and arthropods that is more than 500,000 times larger.

“They have a regular gait and are very similar to animals that are much larger,” wrote one of the research’s authors, Yasmine Nerudi, who works at the Rockefeller University Center for the Study of Physics and Biology.

Could there be a relationship?

Experts argue that this new documentation of the water bear, a species older than insects and other animals by 20 million years, raises new questions about its evolutionary development. They are even open to the idea that they can share grandparents together.

“Tladicorns have a strong and clear way of locomotion, they are not those clumsy things that get stuck in the desert or trash. The similarities between their locomotion strategy and that of much larger insects and arthropods open many very interesting evolutionary questions.” expert.

Tests on different surfaces

The researchers also tested the displacement abilities of tardigrades on surfaces containing more viscous elements such as jelly or honey. The water bears had difficulty moving around on the smooth glass.

“We found that tardigrades adapt their movement to their ‘sprint’ coordination pattern when walking on softer substrates. This strategy has also been observed in arthropods to move effectively on liquid or granular substrates,” the scientists explained in their paper.

Tardigrades, as small as 1.2 millimeters in length, can be found in deserts, glaciers, and other ecosystems that many species – including humans – cannot support. According to scientists, there are at least 1,300 different species.

Edited by Jose Ignacio Origola