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Take a Trip Back in Time This Holiday Season!

Published November 19, 2013

We're celebrating the arrival of our all-new Ice Age: A Mammoth Christmas 4D Experience, by introducing you to some of our favorite "prehistoric" residents here at the Aquarium!

Chambered Nautilus

The chambered nautilus is a mollusk, related to the octopus, squid, clam and snail! Did you know? Nautili are the only cephalopod species that has a fully-developed protective shell.

chambered nautilus

The nautilus is considered to be a "living fossil," as the species has undergone little change in the last 400 million years. The nautilus first appeared about 265 million years before the first dinosaurs.

Did you know? There were about 10,000 different species of nautilus in prehistoric times. Currently, there are six living species of nautilus - all found in the Indo-Pacific.

Horseshoe Crab

Scientists can trace this species back to the Paleozoic Era (before dinosaurs and even flowering plants were around!) - which began 540 million years ago. Incredibly, these "living fossils" have also changed very little over time!

national aquarium horseshoe crab

Although they're commonly known as "crabs," these animals are actually more closely related to arachnids than they are to crustaceans. Their entire bodies are protected by a hard carapace (or shell). Its eyes are able to detect both visible and UV light.

The four remaining species of horseshoe crab can be found worldwide! Limulus polyphemus is the species that we have here - they're found off the East Coast, from Maine to the Yucatan Peninsula (Mexico).


With some species weighing in at 400 lbs, gar are considered the largest freshwater species in North America!

national aquarium longnose gar

Gars can be traced back to the Cretaceous period, which began about 145 million years ago.

Although their ancestors could be found worldwide, today's living species of gar only live in North and Central America. Young gar are preyed upon by larger fish and aquatic birds and reptiles. Once they reach adulthood, they have very few natural predators other than humans.


Survivors of the Cretaceous period, relatives of these elasmobranchs (subclass of cartilaginous fish, such as rays) can be traced back almost 145 million years ago. Historically, the rostrum of the sawfish has been used in religious offerings and traditional medicine.

largetooth sawfish

Did you know? Sawfish are actually considered to be fairly docile animals. However, when provoked, they can cause major damage by swinging their tooth-laden rostrum from side-to-side.

Currently, there are six species of sawfish found worldwide - their distribution ranges from the warm, temperate waters of the Atlantic to the Indo-Pacific! Sawfish are actually a "euryhaline" species, which means they can move between freshwater ad saltwater.


Sturgeon date back as far as 70 million years! The 25 species of sturgeon around today can be found commonly along the Atlantic coast of North America and Europe.

national aquarium sturgeon

Did you know? Sturgeon are prized for their eggs, known more commonly as caviar. In fact, the Beluga sturgeon is responsible for the world's most expensive caviar. Sadly, populations of sturgeon have faced rapid depletion in recent years because of overfishing.


This species belongs to the ancient group of Osteoglossids, which existed in the Jurassic period (close to 220 million years ago)!

national aquarium silver arowana

There are currently 10 living species of this primitive fish, found in South America, Africa, Asia and Australia.

Did you know? All species of arowana are "mouthbrooders," meaning parents will care for hundreds of eggs in their mouths until the young are developed.

Want even more prehistoric fun? Stop by the Aquarium and catch our next screening of Ice Age: A Mammoth Christmas!

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