Illustration of an extinct tentacled sea creature.

Ancient Seas

A Mesozoic Ocean scene

The Ocean Throughout Geologic Time

The ocean has gone through some dramatic transformations over time. This overview dives into our globe's ocean past.

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4,000 Years of Marine History through the Eyes of a Seabird

A Hawaiian petrel in flight

Are You An Educator?

At Smithsonian Ocean, we have lesson plans, activities, and resources to help you engage your students in the wonders of our oceans.
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Ancient Seas Articles

Long Before Coral, Mollusks Built the Ocean's Reefs

A rendering of an underwater marine scene depicting life ~145-65 million years ago, when rudist clams were the major reef builders.

Fossil Whale Found, Excavated, Jacketed, and Returned to STRI!

Smithsonian scientists race the tide the excavate an ancient whale fossil entombed in rock

4,000 Years of Marine History through the Eyes of a Seabird

A Hawaiian petrel in flight

The Discovery of Multispecies Communities of Seacows

An illustration of multispecies communities of dugongs from India, Mexico and Florida

Whale fossils on the mainland, and into a CT scanner

Gabor Szathmary secures one of the plaster jackets containing a fossil "toothed" mysticete that was excavated on Vancouver Island.

At STRI, No Whales Yet, But There Are Fossil Sea Cows...

Smithsonian researchers eat a meal in preparation for a fossil excavation