Why can fleas jump so high?

Answer: Resilin protein stores energy

Legs are extremely long — Wrong. Flea legs are actually short relative to their jumping height. The secret is a rubber-like protein that stores and releases energy explosively.

Resilin protein stores energy ✓ — Correct! Fleas have pads made of resilin—a protein more elastic than rubber. They compress these pads like a spring (using leg muscles), then release explosively! A flea can jump 200x its body length—like a human jumping over a 60-story building!

Lightweight hollow skeleton — Wrong. Being lightweight helps, but the jumping power comes from resilin protein pads that act like compressed springs releasing energy.