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What makes a top predator? Razor-sharp teeth? Speed? Strength? Size? Who is the most fearsome hunter? It depends on where and when you look.
About 100 million years ago , during the heyday of the dinosaurs, reefs were...
For a long time, scientists thought that some small tentacled fossils were...
Sirenians , or seacows, are a group of marine mammals that include manatees and...

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These "elevator" rudists, an ancient bivalve, used one long heavy valve to anchor themselves in the sediment. They used their tentacles (shown here in pink) to filter food from the sea water. And many often grew together to form...
How long have jellyfish lived in the ocean? This jellyfish fossil is from...
Today, filter feeders like clams, sponges, krill, baleen whales, fishes, and...

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When you're standing in a museum surrounded by fossils, you can almost imagine drifting through time to when long-extinct...

The Ocean Blog

Earth’s first animals had soft bodies. This illustration shows a community of soft-bodied Ediacaran (edi-A-karan) animals. Some species resemble living ocean creatures. Others are unlike any known...
A scientific illustration of the most powerful fish of its time, Carcharodon megalodon , which swam the ocean 30 million years ago. This shark may have reached a size of 20 meters/66 feet. Meet other...
Hantkenina mexicana -- a foram with elongated shell chambers that lived between 45-49 million years ago, during the Eocene Epoch. This specimen is from marine sediments that were drilled in the...
Where ocean currents were strong, ancient rudist “recliners” lay unattached on the seabed. Notice the pink tentacles, which were used to filter feed. Learn more about ocean life throughout deep time...
When you're standing in a museum surrounded by fossils, you can almost imagine drifting through time to when long-extinct creatures swam the ocean. Found all over the world, these fossils can be read...
Whales swim, but their ancestors walked. Whales are mammals (like us) whose ancestors lived on land. Life probably began in the ocean and then evolved to colonize the land. Yet the whale’s ancestors...
This illustration shows one old idea of what the ancient shark Helicoprion might have looked like. There once was room for many ideas—some more plausible than others—because the only fossils of the...
For a long time, scientists thought that some small tentacled fossils were early ancestors of jellyfish. But a new study has found that these ancient animals are actually related to an entirely...
This illustration shows the edge of a warm inland sea during the Cretaceous Period, heyday of the dinosaurs. Constantly shifting sediment supported new groups of organisms, including rudist clams—...
Today, filter feeders like clams, sponges, krill, baleen whales, fishes, and many others fill the ocean, spending their days filtering and eating tiny particles from the water. But when did the first...
Reaching almost three feet (one meter) long, Anomalocaris canadensis was enormous for this time period.
The great predator Hurdia victoria’s prey consisted of trilobites and other smaller animals crawling on the seafloor.
Offshore Peru, during the Eocene (~56-34 million years ago), showing three archaeocetes (ancient whales), along with a previously described fossil penguin. Top to bottom: Perudyptes devriesi ,...
Crinoids (echinoderms related to sea stars and sea urchins) dominate the Paleozoic shallow water habitat in this illustration. They evolved a variety of stalk heights, which enabled them to capture...
Monodontids, the group of whales that includes the belugas and narwhals swimming our ocean today, are emblematic symbols of the Arctic. However, their fossil record, although scarce, suggests that...
Dugongs , along with manatees , make up a group of marine mammals called sirenians or seacows . In the modern world, only one species of seacow is found in any one place in the world. However, the...
Rudist clams are mollusks that went extinct about 65 million years ago. They were the reef builders of the Cretaceous Period, the heyday of the dinosaurs. Today corals have taken over the role...
Fossils from the Cambrian period are found throughout the world. The Chengjiang fossil site in china is famous for containing about 196 species of fossils, many from the Cambrian period. The Burgess...
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