What is a living fossil?
A living fossil is an organism that has retained the same form over millions of years and has few or no living relatives.
Here are the survivors that you can see at S.E.A. Aquarium:
Wild Axolotls are only found in the lake complex of Xochimilco near Mexico City. It is an amphibian that uses its external gills for breathing.
Axolotls can regenerate damaged body parts. Scientists have beenstudying them to find out the secrets to their regeneration.
Lungfish (also known as salamanderfish) are freshwater fish belonging to the subclass Dipnoi. Lungfish are the closest link between fish and land vertebrates, including humans. Fossil records of this group date back 380 million years.
While most fish use a swim bladder for buoyancy, the lungfish use it to breathe. The Lungfish walk with their fins and can stay out of the water for days.
Did you know that Arowanas already existed in the Jurassic period which is 199.6 to 145.5 million years ago?
Today, Arowanas are considered symbols of good fortune as they look like the Chinese dragon.
Don’t stand too close to them. Arowanas can leap 2 m out of the water to catch prey!
Tadpole shrimps have not changed significantly in outward form since the Triassic which is 248 to 206 million years ago.
Tadpole shrimps live in small, short-lived ponds that form after flash floods. Therefore, they have fast lifecycles. They can grow from egg to adult in two to three weeks. Their eggs can remain dormant for decades before hatching.
Horseshoe Crabs are relatives of spiders, not crabs. The ancestors of horseshoe crabs date back over 450 million years–long before the age of the dinosaurs.
Horseshoe Crab’s blood has antibacterial properties and is blue because of its copper content. In Singapore, you can find them in the mudflats of Kranji and Mandai.
Singapore’s mangroves are home to eight species of mudskippers. Mudskippers live up to their names and can skip up to 60cm.
Mudskippers are completely amphibious fish that can use their pectoral fins to walk on land. They use colourful dorsal fins to communicate
Alligator Gars are among the oldest fish alive today; their origins can be traced back to the Cretaceous period (145.5 and 65.5 million years ago).
They have two rows of sharp teeth for hunting and eating. Their diamond-shaped scales are common in primitive fish. They can breathe both air and underwater
The African knifefish can generate electrical fields for hunting, navigation and courtship They have a large brain to interpret electrical signals.
The African knifefish are nocturnal and have poor vision. By generating weak electric fields for electro-location, they can hunt in darkness.
Brittle stars were found in the Early Ordovician period, about 500 million years ago. They are scavengers that catch floating food particles in the water.
Brittle stars walk with their arms and are the fastest moving relatives of sea stars.
Nautiluses are relatives of squid and octopuses. The Nautilus is the sole survivor of a once very diverse group of animals called Ammonites. These animals roamed the oceans for 250 millions years before going extinct at the same time as the dinosaurs when a meteorite struck the Earth.
A long winter followed, killing the plankton in the ocean. Ammonite larvae which fed on plankton, died from the lack of food.
Nautiluses do not have a larval stage. When they hatch they prey on shrimps, small fish and scraps instead of plankton. This is why they are still around!
Ancient hermit crabs used ammonite shells as their homes. As hermit crabs grow, they require larger shells. Since suitable shells are sometimes a limited resource, vigorous competition often occurs among hermit crabs for shells.