(Popular Science) What's the fastest animal on earth? Depends on how you define quickness. By simple miles per hour, classic mega-fauna like cheetahs dominate the leaderboard. But if we measure velocity by the body lengths an animal travels per second, those quick cats have some competition. This race of proportions allows contenders from all kingdoms to go for gold. Here's how a cross-section of critters achieves top speeds:

Common Squid
Moves by jet propulsion - This cephalopod shoots through the ocean like a tentacle jet. It sucks water into a chamber in its 8 inch long cone-shaped body, then contracts its muscles to push the liquid through a narrow funnel-shaped organ near its head. The flow blasts in one direction, launching the adult squid's gelatinous form the opposite way at 10 body lengths per second.

Speeding spines - Famous for sheer giddy-up, these spotted cats' flexible spines give their limbs a wide range of motion. The stretch maximizes stride and allows acceleration from zero to 60 mph in three seconds. Hind legs dense with fast-twitch fibers a powerful type of muscle, enable 70 mph bursts. But factor in body size, and they fall behind at 23 lengths per second.

Dive for love - Hummingbirds pump their wings in a figure eight so quickly that humans see only a blur. To impress the ladies, 4 inch long male Anna's hummingbirds accelerate faster than any other vertebrate relative to body size including fighter pilots. Suitors fly at 385 body lengths per second during their customary courtship dive, all powered by outsize pecs.

Might legs - Where there is water, there are copepods serenely floating. In time of crisis, the torpedo-shaped 1-millimeter crustaceans can accelerate to 500 body lengths per second. Two kids of limps some vibrating oars for swimming and some stronger legs for jumping allow the creature to blast over 20 inches, perfect for escaping a fish's gaping jaws.


Popular posts from this blog

Book discussion group to meet

Fall Book Discussion and Movie Series