u/EffectivePride4614

It sounds unbelievable, but sharks are actually older than trees. Sharks have been swimming in Earth's oceans for over 400 million years, while the first trees didn't appear until around 350 million years ago. That means sharks were already roaming the seas nearly 50 million years before forests began covering the planet. 🦈🌳

Two hearts pump blood to the gills, while the third pumps blood to the rest of the body. Interestingly, the main heart stops beating during swimming, which is why octopuses often prefer crawling.