Preserving the Past

Part of the Dinosaurs: Ancient Fossils, New Discoveries exhibition.

Luckily for scientists, the environment of eastern Asia 130 million years ago was well-suited to preserving fossils. When plants and animals died in Liaoning, they often washed into one of the many streams and lakes in the region. More important, they were frequently covered quickly in volcanic ash soon after death. Because the remains were buried so rapidly, many of the Liaoning fossils preserve almost the entire organism.

Delicate Details

Small, delicate bodies decompose more readily than larger ones. Fossils of big animals are rare--and fossils of small organisms are rarer still. But in Liaoning, even small animals were well-preserved. Spectacular fossils of a water strider and a cicada are displayed below

strider

Gerridae (water strider; model based on:)
Early Cretaceous, Barremian (130.0-125.5 million years ago)
Yixian formation, Liaoning, China
Peking University, Beijing

cicada

Cicadidae (cicada; model based on:)
Early Cretaceous, Barremian (130.0-125.5 million years ago)
Yixian formation, Liaoning, China
Peking University, Beijing

 

 

 

Dinosaur for Dinner

This fossil of Repenomamus robustus, a cat-sized early mammal, was found with the remains of a young psittacosaur in its stomach.

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R. robustus.
AMNH/Roderick Mickens
repenomamus_rm.jpg
R. giganticus.
AMNH/Roderick Mickens

 

 

Ghostly Encounters

Fossils usually tell us about the inside of an animal: its bones, muscles and sometimes what it ate for dinner. It's nearly impossible to learn much about how ancient animals looked on the outside. But some Liaoning fossils look like ghosts: The outside of the body is visible as well as the bones. Faint colors and patterns like stripes and spots--even the shading of the eyes--can sometimes be seen.

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Juvenile Psittacosaurus.
AMNH/Denis Finnin

 

 

Scientists aren't sure how colors and patterns were preserved in these fossils. Most likely, the colors in the fossils, just shades of gray, are not the colors of the animals in life. The plants and animals of 130 million years ago were surely just as colorful as those alive today.

Fossil Fish

Large sturgeons swam in the lakes and streams of ancient Liaoning. Fossils of these fish often reveal details such as colors, stripes and spots, as well as the pattern of scales.

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Sturgeon fish.
AMNH/Roderick Mickens