For eons us humans have been obsessed with the quest for immortality, but turns out some animals cracked that code long before we were even mammals. Maybe these creatures will shed some light on one of the life's biggest mysteries.
Here are 8 virtually immortal animals, and I bet some of them, I mean the actual specimens in the pictures, have seen the death of dinosaurs. That's my head canon now!
1. Koi Fish — up to 225 years
I'd never have thought that Koi fish can live up to 225 years! Maybe it's because the Japanese good-luck fish don't have a stomach at all, just the good ol' gut.
2. Tortoises and turtles – up to 255 years
This one's pretty simple – the slower you go, the longer you live (theory requires more testing)! Here's the kicker, there is almost no way you can tell a juvenile turtle from an old one, biologically speaking. It's like being 17 your entire life.
3. Greenland Sharks – 200-500 years
All hail the longest living vertebrate – the Greenland shark! Averaging at 270 years, some specimens are believed to have lived for 450-500 years. Who knows maybe there's a 1000 year old shark somewhere in the depths.
4. Clams – over 400 years
Thanks to their slow cell replacement process clams can live up to and over 400 years!
5. Glass Sponges – 15,000+ years
Do sponges really count as animals? Yes they are, and yes they do seem to live a long life. And guess what, some of these creatures have seen the pyramids being built over 15,000 years ago, and may even see the end of humanity. All hail the Glass Sponge!
6. Hydra – Immortal
Scientists claim that Hydras just don't age. They're truly the perfect organisms, able to divide their cells forever… or until someone eats them.
7. Turritopsis Dohrnii – Immortal
Unlike the Hydra, who can divide its cells effortlessly, this jellyfish's cells can transform into different kinds of cells, depending on what it needs. It can also go back to its polyp stage to heal an injury, and then grow into an adult jellyfish again.
8. Water Bear aka Tardigrades – Immortal
These cute little microscopic life forms have existed on Earth for around 530 million years. Tardigrades can literally stop living thanks to the process called cryptobiosis. Also, their cells don't divide as they age, they just get bigger. Nature, you're crazy!