Have you ever imagined what life was like hundreds of millions of years ago? From enormous dinosaurs roaming the skies, land and sea to colossal plants and animals thriving in a wild landscape, the sights would be astonishing.
At Shedd, go back to the past and get a glimpse of animals that closely resemble their prehistoric ancestors. The “living fossils” here at Shedd will transport you to the time of the dinosaurs.
A living fossil is an organism that has been around for millions of years yet has gone through little evolutionary change when compared to fossil evidence of its extinct ancestors. Through the theory of natural selection living things adapt to survive, so the physical and genetic makeup of an organism will gradually change over time. However, living fossils change only minimally over millions of years.
Let’s investigate which of these remarkable feats of nature you can visit at Shedd:
Fossil evidence dates this freshwater fish back to 380 million years ago. Lungfish biology has remained virtually unchanged for about 100 million years, essentially making lungfish one of the oldest living animals on the planet. The reason for their name is that they have a single lung instead of two, and they’re one of the few fishes with the unique ability to breathe air.
These primitive fish also have an impressive lifespan, with many individuals living to be more than 100 years old. Australian lungfish Granddad, who lived at Shedd for 84 years until his death in 2017, was among that impressive group of long-lasting lungfish. New research indicates his age at death was 109 years, making him the longest-living animal in any zoological setting and deeming Australian lungfish the longest living freshwater sub-tropical fish species in the world.
You can visit these archaic animals at our Rivers exhibit.
The mighty lake sturgeon is the oldest and largest fish native to the Great Lakes. Lake sturgeon appeared in fossil records around 136 million years ago, and the species hasn’t seen much change since. These freshwater giants are heavy and torpedo-shaped with an armor of bony plates covering their body instead of scales, yet their skeleton is made of cartilage instead of bone. Like the lungfish, sturgeons can grow very old, with males reaching an average of 50 years and females reaching 75.
The oldest documented sturgeon was an astonishing 154 years old and was likely female. Sturgeons also face several conservation threats, and because they’re slow to mature and reproduce, it makes rehabilitation and conservation efforts for these fish difficult.
From their paddle-shaped snout to their gapping mouth, these peculiar-looking creatures have inhabited earth's rivers for 125 million years and have retained these unique physical attributes ever since. The name is evidently due to the shape of their snout, which functions as an electro-sensory organ, an ability common among aquatic animals used to detect prey.
They swim with a wide-open mouth — which lacks teeth — to catch their prey along the current. There are only six known species of paddlefish, which have all gone extinct besides the American paddlefish. The Chinese paddlefish was declared extinct in 2022, while the other four disappeared a long time ago.
You can visit these Illinois natives in our Rivers exhibit.
It’s remarkable that some of these animals roamed the earth alongside dinosaurs and have gone through little evolutionary change, yet we still get the chance to see them today.
By: Noah Hedgeman, Digital Marketing Intern