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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

Jorge and I packed up the night we arrived in Panama with Aaron O'Dea and his team from STRI . The road we took in two field vehicles mostly followed the Panama Canal heading northwards; we had to...
This early whale was well suited to life at sea. But it also lived on land. An ancestor of the right whale , Maiacetus lived 49-40 million years ago. It had flipper-like limbs and webbed feet, like...
The Haplophrentis carinatus had two oar-like appendages (called “helens”) used to stabilize the creature and help it move along the ocean bottom.
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...
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...
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...
This rendering shows life at the end of the Cretaceous Period, before the impact of a 6.2 mi (10 km) asteroid triggered mass extinctions on land and sea. Dinosaurs are the most famous victims of the...
The Ottoia prolifica has proven that cannibalism did exist in the Cambrian period since there have been portions of one Ottoia prolifica found in another specimen’s gut.
Humans are late arrivals on Earth. For nearly 75% of Earth’s history, life consisted of single-celled microbes without a nucleus (prokaryotes). Volcanoes and erosion sculpted Earth 3.5 billion years...
Like the modern nautilus, this relative of modern squid hunted from inside the safe haven of a protective shell. Ammonites went extinct around the same time as the dinosaurs—65 million years ago...
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 ,...
Come along as scientist Dr. Brendan Roark narrates a submersible dive to collect and study deep-sea corals. Roark studies deep-sea corals to understand the history of the ocean and past ocean...
The whales that we see in today's world can broadly be split into two groups: those with teeth (odontocetes), and those that have baleen (mysticetes) instead of teeth. These two groups share a common...
Opabinia was a strange looking creature: it had five mushroom-like eyes that allowed it to see predators approaching from many directions.
How long have jellyfish lived in the ocean? This jellyfish fossil is from the Cambrian period, more than 500 million years ago. It was found buried in Utah —an area that used to be underwater,...
The evolution of whales represents one of the great stories in macroevolution. It's a narrative that has mostly benefitted from an extraordinary series of fossils recovered from rocks around the...
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...
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