Jellyfish clone themselves by morphing into a stack of squirming jellyfish pancakes. When grown-up jellyfish love each other very much, they make huge numbers of teeny-tiny potato-shaped larvae.

Scientists are studying the immortal jellyfish, ... baby jellies, which grow to become medusae, the familiar umbrella-shaped, tentacled creatures that pulse along the oceans and mate to spawn eggs.

When grown-up jellyfish love each other very much, they make huge numbers of teeny-tiny potato-shaped larvae. Those larvae grow into little polyps that cling to rocks and catch prey with their ...