Life has existed on earth for hundreds of millions of years and most of those species
have long died off or evolved into other things, but a select few have survived multiple mass
extinction events and still live alongside us today.
So join us as we count the 10 oldest animal species on Earth.
Frilled Shark Frilled sharks are the oldest species of shark
still in existence.
Given their age, they are less evolved than more “modern” sharks, and therefore their
simple bodies appear like some combination of a shark and an eel.
Frilled sharks live at the bottom of the ocean and so, despite being caught occasionally
by accident, they’re rarely encountered by humans.
Sturgeon Sturgeon is technically an umbrella term for
a number of species that have existed for around 200 million years.
Despite their age, nearly every species of sturgeon today is critically endangered because
of humans.
We harvest sturgeons for their roe, which are prized for their use in making caviar.
The problem is that sturgeons take a long time to grow and mature, they can live up
to 100 years, so over-harvesting, pollution and habitat destruction becomes a big threat
to their survival.
Thankfully, they can produce millions of eggs.
Unfortunately, we keep eating all of them.
Horseshoe Shrimp The Horseshoe shrimp are the oldest living
shrimp on Earth, dating over 200 million years on the planet.
Since the beginning of their existence, evolution hasn’t altered the shrimp at all, which
we know because we have horseshoe shrimp fossils from 200 million years ago, which show an
animal that is exactly the same as the ones that are still swimming around today.
Tadpole Shrimp The Tadpole Shrimp has been around for over
200 million years, but today they are classified as an endangered species.
Fortunately, they still have a chance of survival as in 2010 scientists discovered a unique
trait.
It seems their eggs can lie dry and dormant for very long periods and still create new
life when rehydrated.
Lamprey Lampreys are parasites that resemble eels
with circular mouth holes filled with loads of small sharp teeth that they can use to
attach themselves onto fish and suck their blood.
Their tactics must be quite effective though, as in 2006 scientists studied a 360 million
year old lamprey fossil that was pretty much exactly the same as the lampreys we have today.
Coelacanth Up until 1938 we believed Coelacanths were
already extinct, but then we found one.
Since then, scientists have studied this very rare, endangered fish because they are very
similar to the ancient fish that eventually evolved to crawl out of the water and become
the first land vertebrate.
Understanding the genetic footprint of the coelacanths is important in allowing us to
understand how they evolved into many different land vertebrates.
Horseshoe Crab These crabs are actually called “living
fossils” because they have been around for an incredibly long time, 445 million years
to be exact.
A decline in the population of these creatures has been seen due to coastal habitat destruction
as well as overharvesting in the east coast of North America.
While these creatures have been around for a very long time, they’ve stayed the same
throughout the years proving that this is one successful species.
Nautilus The Nautilus is a marine mollusk that splits
down into further sub-species.
These creatures have been living in the seas and oceans of our planet for over 500 million
years, surviving every major mass extinctions that we know of and as with other species
on this list, they haven’t evolved much in that time.
Today, they are under threat of extinction due to humans harvesting the unique looking
spiral shells from the nautilus to use them as decorations.
So a species that has been around for half a billion years is all of a sudden vulnerable
because of us humans, just think about that for a second.
It’s quite sad really.
Jellyfish Jellyfish are getting very close to the oldest
animals on Earth.
Jellyfish have roamed the seas for at least 500 million years, and possibly 700 million
years or more, making them the oldest multi-organ animal in the world.
In 2007, researchers from the University of Kansas found some new evidence in the form
on fossils to prove that jellyfish had in fact been around for at least half a billion
years, over 200 million years more than the oldest known jellyfish fossils at the time.
But in reality jellyfish could be even older, we just don’t know yet.
Sponge Sponges are multicellular organisms that have
bodies full of spores and channels allowing water to circulate through them.
It’s unclear exactly how long they’ve been around but it’s very likely that they
are the longest existing creatures on Earth, excluding microorganisms like bacteria.
The oldest found evidence of a sea sponge fossil was discovered in 2015 and dates to
be around 650 million years old.
Of course, there may yet be older fossils left to find.