Lampreys Although they have an eel-like appearance, these creatures are actually jawless fish. And they’ve got one of the most frightening mouths in the entire animal kingdom. The orifice has a funnel shape that contains sharp teeth used to bore into the flesh of their prey to suck out the blood … but only certain species engage in that behavior. Their fossils have been dated back around 360 million years … and they seem have evolved very little in that time.
Sea Sponge Researchers find it difficult to calculate just how long sea sponges have been around. But the oldest fossil of one of these creatures was actually discovered in a rock … that was around 750-million years old.
Horseshoe Crab These arthropods managed to outlast the dinosaurs. Experts have dated these arthropods back to some 450 million years ago, and they’re pretty much unchanged since then. The strange-looking creatures have a hard carapace that protects their body. And while they resemble crustaceans, they belong to a different subphylum. Did you know that these critters have a total of 10 eyes?
Platypus We mentioned earlier that the Echidna was one of only two mammalian species that lay eggs … Now here’s the other one. As we said earlier the two animals are thought to have split off from a common ancestor around 50 million years ago. But researchers say fossil evidence of that common ancestor could date back around 110 million years.
Australian Ghost Shark Distantly related to sharks and rays, these animals belong to a branch of cartilaginous (cart-ill-ahg-in-us) fish called chimeras (KIH-meras). When scientists mapped the creature’s genome, it revealed DNA that’s gone basically unchanged for almost 420 million years. Also known as Elephant sharks, they are now considered to be the slowest-evolving vertebrates known to date.
Alligator Snapping Turtle This looks like it could be a dinosaur emerging from a swamp, kind of like something you’d see in one of the Jurassic Park movies. But the creature in the picture does exist in real life, although it’s not as big as it seems to appear. That’s not to say the Alligator Snapping Turtle is small, though. Weighing more than 175 pounds, they’re one of the world’s heaviest freshwater turtles … that’s with a carapace that can exceed 30 inches. Some experts estimate their history goes back more than 150 million years.
Coelacanth (SEE-luh-kanth) It was once believed that these rare fish went extinct about 65 million years ago. But in 1938 they were re-discovered off the coast of South Africa, and it turned out this animal was even more durable than originally thought. Experts think they evolved into their current form around 400 million years ago.
Ctenophores (Jellyfish) Known as ctenophores (steni-fores), these animals showed up some 700 million years ago. They propel their gelatinous bodies through the water using rows of cilia, or combs. Biologists claim these are the oldest known animals, which means humans could be descended from these things. Hope we enjoy the same longevity as this so called living fossil!