Ankle Spur Protects From Predators

photograph of brown platypus swimming in water

Biological Strategy

Platypus

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Image: Darren Puttock / Flickr / Some rights reserved

Protect From Animals

Animals–organisms that range from microscopic to larger than a bus–embody a wide variety of harms to living systems, including other animals. They threaten through predation, herbivory, defense, and parasitism, and they compete for resources such as water, nutrients, and space. Any given living organism commonly faces threats from a variety of animals, requiring strategies that effectively defend from each. Trout and other bony fish, for example, escape predators by having scales made of very thin, flake-like pieces of bone covered with slippery mucus. They also have behavioral strategies such as camouflage, fast swimming, and twisting and turning to achieve release from a predator’s grip.

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Mammals

Class Mammalia (“breast”): Bats, cats, whales, horses, humans

Mammals make up less than 1% of all animals on earth, but they include some of the most well-known species. We know first-hand some of the characteristics that make mammals unique, like having hair, being able to sweat, and producing milk through mammary glands. Another critical shared feature is a set of highly-specialized teeth. Unlike sharks or alligators, for example, whose teeth are generally all the same size and shape, mammals have differently shaped teeth in different areas of the jaws to target specific foods or foraging strategies.

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The back legs of a male platypus provide defense against predators and other males via poisonous spurs.

Image: E. Lonnon / Wikimedia Commons /

Image: Pedro Lopez /

“One last peculiarity of the platypus is the sharp horny spur on the back feet of the males, through which poison from a poison inside the leg can be injected with a slashing kick. The spur is used in defence and against other males in contests, and the poison is strong enough to be dangerous to humans — not that many of them come into contact with platypuses.” (Foy and Oxford Scientific Films 1982:182)