Its flat body settles down atop the algae like a suction cup. When the animal finds a patch of algae, it stops. The animal moves by twirling these cilia like propellers. He’s a zoologist who has been studying Trichoplax for 25 years.Ĭells on the underside of Trichoplax have tiny hairs called cilia (SILL-ee-uh). He works at the Institute for Animal Ecology and Cell Biology in Hannover, Germany. This “division of labor between cell types” is a hallmark of animals, explains Bernd Schierwater. And though this animal lacks a stomach or heart, its body is organized into different kinds of cells that perform different tasks. In contrast, the body of a Trichoplax has at least 50,000 cells. Some amoebas are larger than this animal. But when Schulze looked through his microscope in 1883, he could see several clues that Trichoplax truly was an animal. Amoebas are a type of protist, single-celled organisms that are neither plants nor animals. As such, it resembles a blob called an amoeba (Uh-MEE-buh). Its flat body constantly changes shape as it moves. A hungry suction cupĪt first glance, Trichoplax does not even look like an animal. Trichoplax is even providing hints about how simple animals later evolved more complicated bodies - with mouths, stomachs and nerves. It shows what the very first animals on Earth might have looked like, 600 million to 700 million years ago. But scientists are interested in Trichoplax precisely because it is so simple. It is nothing but a flat sheet of cells, thinner than paper. It has no mouth, no stomach, no muscles, no blood and no veins. To this day, Trichoplax remains the simplest animal known. That’s Latin for “hairy sticky plate” - which is about what it looks like.

Schulze named it Trichoplax adhaerens (TRY-koh-plaks Ad-HEER-ens). It was hiding in one of his fish tanks. Creeping along the inside of the glass, it was dining on the green algae that grew there. He discovered it one day by pure accident. Others resembled miniature castles with pointy towers.īut today, Schulze is best remembered for something very different - a drab little animal no larger than a sesame seed. They were striking - brightly colored with exotic shapes. He found many new species and filled saltwater aquariums at the University of Graz in Austria with these simple sea animals. In the 1880s, he was one of the world’s top experts on ocean sponges.

Living Mysteries launches as an occasional series on organisms that represent evolutionary curiosities.įranz Eilhard Schulze had a laboratory full of beautiful sea creatures.

Do sponges havelegss to move