The Animals That Exist Between Life and Death

Summary

In the late 1600s, self-made scientist Antonie van Leeuwenhoek embarked on a project that would make him question the very nature of life and its limit. And would send ripples of philosophical and scientific quandaries through the generations that persist today. Peering through the hand-ground lenses he crafted, magnifying his subjects 275 times, the Dutch cloth merchant and naturalist was the first human to glimpse an otherworldly microcosmos where astonishing creatures seemed to defy the laws of nature and survival. He called them, adoringly, “animalcules.” In 1687, he discovered some animalcules so peculiar in form and function that he would spend decades observing them. We now know these tiny animals, which had wheel-like appendages that van Leeuwenhoek correctly surmised were for feeding, as rotifers. They live in watery environments throughout the globe, from the tropics to Antarctica, in oceans, temporary puddles, and even in moisture within moss. But van Leeuwenhoek wasn’t satisfied just watching them. He decided to test these ubiquitous animals’ limits. He wanted to see what would happen to them when their surrounding aqueous environment dried up.Other animalcules, he noted, would readily break apart or collapse in on themselves upon desiccation. But when he dried out rotifers, they each instead contracted into a shrunken, wrinkled oval, now called a “tun” or “xerosome.”Philosophers are still grappling with the idea that life and death may not be the only states of being. ADVERTISEMENT Nautilus Members enjoy an ad-free experience. Log in or Join now . What van Leeuwenhoek discovered next went beyond anything he could have imagined: After adding water to a glass tube that contained dried sediment and rotifer tuns he’d collected from a rain gutter, van Leeuwenhoek watched in wonder through his homemade microscope as rotifers came back to life. “I examined it, and perceived some of the Animalcules lying closely heaped together,” he wrote in a letter to the Bri...