Seeing photos of cold-stunned iguanas in Miami during a winter cold spell brought back an early memory. I was a 7th-grade intern in the reptile house at Audubon Zoo in New Orleans, when I jumped into a concrete pit with a dozen of the big lizards. The zookeeper had given me permission to get an up-close look. Moments later, I scrambled out of the pit after quickly learning one way iguanas defend themselves: All had begun lashing their tails at my bare ankles and legs. An adult iguana’s tail can be 2-feet long, and the swishing sounds were impressive—unquestionably an educational experience. I doubt zoos today encourage teenagers to find out firsthand that iguanas can whip you.

All animals have other animals that can harm them. All species still with us on earth have developed defenses to protect themselves from predators. Camouflage is a common passive approach. A green frog sitting in green vines is virtually invisible to most people. An active response by many prey involves a flight-or-fight decision. Rapid escape is an effective response for some: a chipmunk running from a coyote, a Carolina wren flying up into a tree. Fighting back is the last, and sometimes successful, resort for countless prey when they are cornered or caught. Biting (snakes), scratching (cats) and exuding a bad smell (skunks) are common last-line defenses. Using the tail as a weapon is a common tactic of some animals more familiar to most people than big lizards—think scorpions and stingrays.

Animal tails come in many guises, including prehensile ones used for climbing (possums), decoys to divert an attack away from the body (blue-tailed skinks) and lures to attract prey (baby copperheads). In the animal kingdom, the ability to use the tail defensively has been around for a long, long time. An excellent scientific summary of “tail weaponization” in Proceedings of the Royal Society B: Biological Sciences by Victoria M. Arbour and Lindsay E. Zanno (North Carolina State University) covers the gamut of mammals, birds and reptiles from the age of dinosaurs to the present day. Tail armaments have appeared in many forms, in unrelated groups of animals over millions of years. The authors note most of these animals are large in body size, have body armor and are plant eaters.

A quintessential example of tail weaponry appeared on earth about 150 million years ago in a well-known dinosaur. Every child with a dinosaur book knows what a Stegosaurus looks like, with big armored plates standing up on the back and top of the tail like bony sails. These behemoths walked around on land eating trees and other plants. Despite their gigantic size, they were viewed as prey by the equally huge Allosaurus dinosaurs that had enormous, toothy mouths and walked on two legs like a T. rex. Stegosaurus, however, had a surprise in store for a hungry carnivore that thought it would partake of a tasty snack. The end of the herbivore’s tail was a bundle of enlarged spikes that, when swung around, would maim any creature that has ever walked the earth. Tail weaponry at its finest.

We still have examples today of tails being used for protection. Anyone trying to catch a big alligator must beware the powerful jaws and the equally powerful, though toothless, tail. I saw a colleague knocked completely off his feet when he stood too close to a captured alligator. Horses and cows use their tails to swat away flies, which qualify as blood-sucking predators. Porcupines use their tails to whack a bobcat that gets too close, ensuring the quills have some momentum behind them.

All animals have evolved defenses against natural predators, but few have mastered ways to deal with the unnatural hazards presented by humans. Highway deaths, pesticide pollution and widespread destruction of natural habitats are all relatively new threats to today’s wildlife. Sadly, even tail weaponry can’t compete with such assaults.

Send environmental questions to ecoviews@gmail.com