Witness the Rare Birth of a Water Bear

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WAter bears are among the most resilient creatures on Earth: these fancifully shaped microscopic animals can survive extreme radiation, a hypothetical apocalypse, dehydration and starvation, and have even persevered in the harsh conditions of space. And yet, like so many other living beings, they are still vulnerable when they enter the world.

In the video below, you can see a baby water bear, also known as a tardigrade, making its first efforts to become independent. Under the microscope, the mother drags her babies around a petri dish in a large bag of partially molted skin. When she finally removes it, an egg releases and the water bear inside pokes and prods with its mouthparts to break out of its shell and break free.

According to tardigrade researcher Witold Morek of the Wellcome Sanger Institute, water bears have two egg-laying strategies. They can lay their eggs in the exuvium, the mother’s exoskeleton, or freely in the environment, he explains. Nautilus by email. Eggs laid in the molt’s skin have smooth surfaces, while those laid freely tend to have a more ornate exterior.

The common explanation, says Morek, although there is no experimental evidence yet, is that these different birthing strategies help babies stay in place in the moss or lichen where they are often born. The ornaments protect those released directly into the environment from being washed away by rain. The shed’s exoskeleton serves a similar purpose for the water bear eggs it contains.

Water bears got their nickname from a German theologian named Johann August Ephraim Goeze in the 1770s. He was one of the first to observe them under a microscope and chose the nickname because of their bulbous, bear-like shape and because he found them in a nearby pond. These tiny, strange creatures, which live in a wide range of environments, from moss to glaciers, have attracted the fascination of scientists and science enthusiasts ever since. We now have a rare glimpse into how these tenacious creatures take their first steps into the wild.

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Main image: Bob Goldstein and Vicky Madden, UNC Chapel Hill / Wikimedia Commons

• Kristen French

  Published on October 27, 2025

  Kristen French is an associate editor at Nautilus. She has worked in science journalism since 2013, reporting and editing features and news for publications such as Wired, Rear channel, The edgeAnd new York magazine, among others. She studied science journalism at Columbia University. She is based in San Diego.