Evolution

The Oldest Known Human Ancestor Is A Tiny Thing With No Anus

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You probably resemble your parents at least a little bit. Maybe you even look like your grandparents, or their grandparents. Go back far enough, though, and you'll struggle to find much in common with your early ancestors—especially this one. In 2016, scientists discovered what may be humans' oldest known ancestor, and it looks basically like an alien mouth the size of a grain of sand.

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Artist’s reconstruction of Saccorhytus coronarius, based on the original fossil finds. The actual creature was probably no more than a millimeter in size.

Say Hello To Your Great-Great-Great Ad-Infinitum Grandparent

Isn't she purdy? This ancestor, whose fossil was discovered in August 2016 by an international team of researchers, is known as Saccorhytus coronarius. A study published in January 2017 in the journal Nature describes our long-lost cousin like this: "The bag-like body bears a prominent mouth and associated folds, and behind them up to four conical openings on either side of the body as well as possible sensory structures. An anus may have been absent, and correspondingly the lateral openings probably served to expel water and waste material." In summary, this tiny little thing the size of a grain of sand was basically a large, wrinkly mouth and it probably lacked an anus—one main entrance, no main exit.

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Photographs of the fossils show the spectacularly detailed levels of preservation which allowed researchers to identify and study the creature.

See The Resemblance Yet?

Yes, the 540 million-year-old sea creature looks like an alien potato. But, surprisingly, you have a lot more in common with this thing than it may seem on the surface. This little buddy was bilaterally symmetrical, meaning it had mirrored halves. This is a key feature of many of its descendants, including—you guessed it—us. This discovery is significant because it gives us great insight into the earliest stages of the group that led all the way to modern humans.

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Key Facts In This Video

  1. Anthropologist Richard Wrangham believes that cooking food allowed humans to transition from primitive primates to complex humans. 00:59

  2. Around 1.8 million years ago, the first modern humans emerged, boasting larger brains and smaller jaws. 02:34

  3. Spending less time eating would have enabled our ancestors to spend time developing art, language, and tools. 04:34

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