This worm-like creature is the first ancestor on the human and animal family tree

By Ashley Strickland, CNN

Updated 3:00 PM ET, Mon March 23, 2020

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The Okavango Delta in Botswana showcases a patchy landscape where the ability to plan results in a huge survival payoff.
Photos: Ancient finds
The Okavango Delta in Botswana showcases a patchy landscape where the ability to plan results in a huge survival payoff.
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This is a clutch of fossilized Protoceratops eggs and embryos, discovered in the Gobi Desert of Mongolia. They provide evidence that dinosaurs laid soft-shell eggs.
Photos: Ancient finds
This is a clutch of fossilized Protoceratops eggs and embryos, discovered in the Gobi Desert of Mongolia. They provide evidence that dinosaurs laid soft-shell eggs.
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These tools, made from the bones and teeth of monkeys and smaller mammals, were recovered from Fa-Hien Lena cave in Sri Lanka. The sharp tips served as arrow points.
Photos: Ancient finds
These tools, made from the bones and teeth of monkeys and smaller mammals, were recovered from Fa-Hien Lena cave in Sri Lanka. The sharp tips served as arrow points.
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This labeled map shows the complete ancient Roman city of Falerii Novi as it currently exists underground.
Photos: Ancient finds
This labeled map shows the complete ancient Roman city of Falerii Novi as it currently exists underground.
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Fragments of the Dead Sea Scrolls found in the 1950s are seen here.
Photos: Ancient finds
Fragments of the Dead Sea Scrolls found in the 1950s are seen here.
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This is one of the 408 human footprints preserved at the Engare Sero site in Tanzania. The fossilized footprints reveal a group of 17 people that traveled together, likely including 14 women, two men and one juvenile male.
Photos: Ancient finds
This is one of the 408 human footprints preserved at the Engare Sero site in Tanzania. The fossilized footprints reveal a group of 17 people that traveled together, likely including 14 women, two men and one juvenile male.
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Blade-like stone tools and beads found in Bulgaria's Bacho Kiro cave provide the earliest evidence for modern humans in Europe 47,000 years ago.
Photos: Ancient finds
Blade-like stone tools and beads found in Bulgaria's Bacho Kiro cave provide the earliest evidence for modern humans in Europe 47,000 years ago.
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This artist's illustration shows what an early, small ichthyosaur that lived 248 million years ago may have looked like. It resembled a cross between a tadpole and a seal, grew to be one foot long and had pebble-like teeth that it likely used to eat invertebrates like snails and bivalves.
Photos: Ancient finds
This artist's illustration shows what an early, small ichthyosaur that lived 248 million years ago may have looked like. It resembled a cross between a tadpole and a seal, grew to be one foot long and had pebble-like teeth that it likely used to eat invertebrates like snails and bivalves.
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This is an artist's illustration of Adalatherium hui, an early mammal that lived on Madagascar 66 million years ago.
Photos: Ancient finds
This is an artist's illustration of Adalatherium hui, an early mammal that lived on Madagascar 66 million years ago.
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This is an artist's illustration showing a cross-section of Earth's forming crust approximately 3 to 4 billion years ago.
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