Immortal jellyfish

When life gets too rough, the immortal jellyfish just hits the ultimate reset button. If it gets hurt or starts starving, it melts its own tentacles, sinks to the seafloor, and turns into a tiny blob of slime. In just 36 hours, that blob grows into a new coral-like colony that sprouts brand-new baby clones of itself—basically like a butterfly turning back into a caterpillar whenever it wants.