Venomous Spines
Venomous Spines
Prickly hairs, spikes, quills, and spines on an animal’s body help defend it. They can be irritating or painful, or difficult to swallow. Among the ranks of these bristly beasts are animals whose spines also are venomous.
Caterpillars of different species, for example, often have barbed hairs as part of their defense systems. The hairs irritate predators. Some species’ hairs also are attached to venom glands. These hairs not only pierce predators, but also inject venom. Often a predator is jabbed merely by touching the caterpillar. Some kinds of caterpillars arch their bodies to stab their spines into a predator as it attacks.
The saddleback caterpillar is a bristly brown caterpillar with a green “saddle blanket” on its back. When its hairs are touched, they stick in the predator’s skin and their tips break off, allowing venom to flow out from the caterpillar’s body through the hollow hairs. Saddlebacks are found in the eastern United States. A saddleback’s sting causes pain and swelling at the site of the sting, and can make a person feel nauseated.
Flannel moth caterpillars also have venomous hairs. The fuzzy caterpillars look soft enough to pet, but their powerful venom causes severe pain and swelling. Some flannel moth caterpillars in South America have such strong venom that they can temporarily paralyze a human. in Brazil, they are known as “fire beasts” because of their painful sting. Another South American caterpillar, the larva of the giant silkworm moth, inflicts stings that can be deadly to humans.
Venomous spines also are found on a number of sea creatures, such as stingrays. Stingrays are flat-bodied cousins of sharks. They hunt for clams, worms, and other prey on the seabed in shallow water, and often half-bury themselves in sand and mud when resting. Their tails are armed with sharp spines that are notched along their edges like saw blades.
Stingrays use their spines to defend themselves from predators, such as sharks. A frightened stingray lashes its spiny tail over its back to sting its foe. It also stings people who step on it.
Fireworms, some sea urchins, and the crown-of-thorns starfish also rely on sharp, venomous spines for protection. The fireworm is covered with hollow bristles that break off easily in a predator’s skin and allow venom to seep into it. The burning pain that results gives the fireworm its name. A fireworm warns that it is dangerous by flaring its bristles.
A sea urchin is a prickly pincushion at all times. An urchin’s spines pierce and break off in a predator’s skin. Venomous long-spined sea urchins give predators a dose of venom as well as an injury, because venom flows from the broken spines. Some species’ spines are covered with venomous skin, which leaks venom when the spine stabs an animal. The crown-of-thorns starfish, a relative of urchins, also delivers its venom in this way.
An urchin, which can sense light and dark, can pinpoint its attacker and then aim its spines in that direction. The most venomous urchin, called the flower urchin, has nonvenomous spines. However, it has miniature sets of venomous jaws hidden among its spines.
Other species have venomous spines in their fins. Like stingrays, these fish use their spines only for defense. The weeverfish, found along British beaches, hunts by lying hidden in the sand in shallow water. It has venomous spines in its back fin and over its gills. It doesn’t use these on the shrimp and small fish that it snaps up as they swim by, but a fish that tries to eat the weeverfish will be confronted by these weapons.
Venomous toadfish nestle in sand in the warm, shallow waters of Central and South America. Like weevers, they sport venomous spines on their backs and gill covers. Their drab, brown-and-gray coloring helps camouflage them as they lie in wait to catch fish and other small prey with their wide, toothy mouths. The hollow spines are used only for injecting venom into predators.
Another well-camouflaged fish of shallow ocean water is the warty, slow-moving stonefish. It releases venom when the spines in its back fin are pressed. The venom shoots along grooves in the spines and into the injury caused by the pointy tips. Stonefish live in parts of the indian and western Pacific oceans. Their venom is the deadliest of any fish. People get stung when they accidentally step on a stonefish. Sharks and rays get stung when they close their jaws on one. Not all venomous fish are sluggish, bottom-dwelling species. The gaudy lionfish, with its bright colors and large fins, is a vivid sight as it swims among other coral reef fish. Its beautiful fins, however, contain venomous spines. A lionfish uses them to defend itself and will turn to face a predator, spreading out its spiny fins in warning. Worldwide, there are about 1,200 kinds of venomous fish— more than twice the number of venomous snake species.
Prickly hairs, spikes, quills, and spines on an animal’s body help defend it. They can be irritating or painful, or difficult to swallow. Among the ranks of these bristly beasts are animals whose spines also are venomous.
A sharp, venomous spine on a stingray’s tail helps it defend itself from predators, such as sharks. |
Caterpillars of different species, for example, often have barbed hairs as part of their defense systems. The hairs irritate predators. Some species’ hairs also are attached to venom glands. These hairs not only pierce predators, but also inject venom. Often a predator is jabbed merely by touching the caterpillar. Some kinds of caterpillars arch their bodies to stab their spines into a predator as it attacks.
The saddleback caterpillar is a bristly brown caterpillar with a green “saddle blanket” on its back. When its hairs are touched, they stick in the predator’s skin and their tips break off, allowing venom to flow out from the caterpillar’s body through the hollow hairs. Saddlebacks are found in the eastern United States. A saddleback’s sting causes pain and swelling at the site of the sting, and can make a person feel nauseated.
Flannel moth caterpillars also have venomous hairs. The fuzzy caterpillars look soft enough to pet, but their powerful venom causes severe pain and swelling. Some flannel moth caterpillars in South America have such strong venom that they can temporarily paralyze a human. in Brazil, they are known as “fire beasts” because of their painful sting. Another South American caterpillar, the larva of the giant silkworm moth, inflicts stings that can be deadly to humans.
Venomous spines also are found on a number of sea creatures, such as stingrays. Stingrays are flat-bodied cousins of sharks. They hunt for clams, worms, and other prey on the seabed in shallow water, and often half-bury themselves in sand and mud when resting. Their tails are armed with sharp spines that are notched along their edges like saw blades.
A large stars-and-stripes toadfi sh swims over a coral reef. Toadfish use their venomous spines against predators, and their camouflaged body color and spines help them hunt prey. |
Stingrays use their spines to defend themselves from predators, such as sharks. A frightened stingray lashes its spiny tail over its back to sting its foe. It also stings people who step on it.
Fireworms, some sea urchins, and the crown-of-thorns starfish also rely on sharp, venomous spines for protection. The fireworm is covered with hollow bristles that break off easily in a predator’s skin and allow venom to seep into it. The burning pain that results gives the fireworm its name. A fireworm warns that it is dangerous by flaring its bristles.
A sea urchin is a prickly pincushion at all times. An urchin’s spines pierce and break off in a predator’s skin. Venomous long-spined sea urchins give predators a dose of venom as well as an injury, because venom flows from the broken spines. Some species’ spines are covered with venomous skin, which leaks venom when the spine stabs an animal. The crown-of-thorns starfish, a relative of urchins, also delivers its venom in this way.
An urchin, which can sense light and dark, can pinpoint its attacker and then aim its spines in that direction. The most venomous urchin, called the flower urchin, has nonvenomous spines. However, it has miniature sets of venomous jaws hidden among its spines.
A lionfish spreads out its venomous spiny fins in warning. |
Other species have venomous spines in their fins. Like stingrays, these fish use their spines only for defense. The weeverfish, found along British beaches, hunts by lying hidden in the sand in shallow water. It has venomous spines in its back fin and over its gills. It doesn’t use these on the shrimp and small fish that it snaps up as they swim by, but a fish that tries to eat the weeverfish will be confronted by these weapons.
Venomous toadfish nestle in sand in the warm, shallow waters of Central and South America. Like weevers, they sport venomous spines on their backs and gill covers. Their drab, brown-and-gray coloring helps camouflage them as they lie in wait to catch fish and other small prey with their wide, toothy mouths. The hollow spines are used only for injecting venom into predators.
Another well-camouflaged fish of shallow ocean water is the warty, slow-moving stonefish. It releases venom when the spines in its back fin are pressed. The venom shoots along grooves in the spines and into the injury caused by the pointy tips. Stonefish live in parts of the indian and western Pacific oceans. Their venom is the deadliest of any fish. People get stung when they accidentally step on a stonefish. Sharks and rays get stung when they close their jaws on one. Not all venomous fish are sluggish, bottom-dwelling species. The gaudy lionfish, with its bright colors and large fins, is a vivid sight as it swims among other coral reef fish. Its beautiful fins, however, contain venomous spines. A lionfish uses them to defend itself and will turn to face a predator, spreading out its spiny fins in warning. Worldwide, there are about 1,200 kinds of venomous fish— more than twice the number of venomous snake species.