66 million years ago, a giant meteor struck Earth and wiped out the dinosaurs. When nearly every dinosaur went extinct, many prehistoric animals survived the apocalypse and withstood the test of time.
Some of these ancient animals survived with little to no change in their appearance and behaviour.
Here are some prehistoric animals that still exist today.
The lamprey is a jawless fish with a bizarre funnel-type mouth that has many tiny teeth. It is an ancient eel-like creature known for boring its way into the flesh of other fish and draining their blood.
Ancient fossils reveal that the lamprey has remained almost unchanged for 360 million years. At the centre of its mouth is a structure comparable to a tongue, known as a piston. It bears 3 sharp chompers, of which 2 move sideways, and another that moves up and down.
This critter typically preys on smaller schooling fishes such as herring and trout. It skeletonises the fish until it dies from massive blood loss, infection or just by having a big hole in its body.
The echidna is a small and solitary mammal, also known as a spiny anteater. The echidna species and duck-billed platypus are the only remaining members of the monotremes, or egg-laying mammals.
Echidnas and platypuses are believed to have split into separate species sometime between 48 and 19 million years ago.
An echidna has spines like a porcupine, a beak like a bird, a pouch like a kangaroo and it lays eggs like a reptile. It is toothless and uses its long, sticky tongue to feed on ants, termites, worms, and insect larvae. It breaks food down with hard pads on the roof of its mouth and back of its tongue.
It is a living fossil believed to be a strange surviving link between reptiles and mammals.
The tadpole shrimp is a living fossil that has remained exactly the same since the Triassic period 220 million years ago. It is the oldest living animal species known. This means that it walked the Earth with the dinosaurs and endured the cataclysmic event which wiped them out.
With its distinctive body shape of an oval shell-like cover, a slender abdomen, and a long, forked tail, the tadpole shrimp resembles a small horseshoe crab.
The species can be found across Europe, Russia, India and the Middle East.
Due to the uncertain nature of their habitat in ponds, tadpole shrimps have extremely short lifespans. Depending on the temperature of the pond, they develop from eggs to adults in a matter of 2 to 3 weeks. When the pond dries out, the resistant eggs can remain dormant for decades until the pond is re-flooded.
The frilled shark gets its name from the frilly appearance of its gill slits. It is considered a living fossil because evidence of its existence dates back to around 80 million years.
Its mouth is lined with 25 rows of backward-facing, trident-shaped teeth. It has 300 teeth in total.
Frilled sharks use their bright white teeth, which contrast against their brown bodies, to lure in prey. Scientists believe that their posterior fins are used as propulsive surfaces to launch themselves at their prey.
Their long jaws may also help them to gape extra wide and consume prey half the length of their own bodies.
According to the ReefQuest Centre for Shark Research, “its body cavity is elongate and packed with a huge liver perfused with low-density oil and hydrocarbons, making the shark almost neutrally buoyant at depth.”
Scientists claim that the frilled shark has remained the same since the Cretaceous Period, when the Tyrannosaurus rex and Triceratops were alive. This is most likely due to the lack of nutrients in its deep-sea dwellings.
A Japanese study of the frilled shark found in Suruga Bay, Japan, revealed that its diet is 61% cephalopods, including squids and octopuses, 11% teleost fishes, and occasionally, other sharks.
The sandhill crane is a prehistoric species with one of the longest fossil histories of any existing bird. The oldest fossil dates back 2.5 million years, which makes it older than many of the living species of birds today.
Sandhill cranes are very large, tall birds with long thin legs and necks. They stand between 0.9 to 1.2 metres and have a wingspan of 1.8 metres when fully grown. Their weight varies between 3.6 to 5 kilograms.
They are known for their courtship performances where 2 cranes face each other while leaping with outspread wings. While doing so, they bow, call and toss bits of grass into the air.
As the cranes are wetland birds, they are sensitive to water shortages and droughts. They are also especially sensitive to habitat loss as they roost at night in shallow wetlands and feed by day in agricultural fields. To get from one to the other, they have to travel up to 19 kilometres.
The tuatara is the sole survivor of an ancient group of reptiles in the middle Triassic Period about 238 to 240 million years ago. It is distantly related to lizards, snakes and worm lizards.
It is sometimes referred to as a “living dinosaur” because of its primitive body structure that has remained unchanged for millions of years.
It is mostly nocturnal and basks in the day at its burrows. It preys on arthropods, smaller lizards, prion eggs and chicks.
It has a third, or parietal, eye on the top of its head. The third eye is not an organ of vision, but rather, helps to register the circadian rhythm for hormone regulation.
The stapes is a small bone found in its middle ear cavity that conducts sound vibrations, making the tuatara most sensitive to sound in the 100 to 800 Hertz range.