Defense Mechanisms Animals Use to Survive

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Defense mechanisms are crucial to all animal life. Since animals in every biome must eat to survive, prey animals must constantly avoid being eaten. Animals employ adaptations that add to the chances of survival for the species. Some of these adaptations include defense mechanisms—things that can give prey an advantage against their enemies.

There are several ways animals avoid falling prey to a predator. One way is very direct and comes naturally. Imagine you are a rabbit and you have just noticed a fox preparing to attack. What would be your initial response? Right, you'd run. Animals can use speed as a very effective means of escaping predators. Remember, you can't eat what you can't catch!

Camouflage

Another defense mechanism is camouflage or protective coloration. One form, cryptic coloration, allows the animal to blend in with its environment and to mask its identity. Cryptic coloration is important to the survival of many new-born and young animals, as it is often their main defense against being detected by predators. Some animals blend in so well with their environment that it is very difficult to identify them. For example, some insects and other animals can look like leaves; both in their visual appearance and their behavior. It is important to note that predators also use cryptic coloration to avoid detection by unsuspecting prey.

Playing Dead

When faced with danger, some animals pretend to be dead. This type of adaption is known as thanatosis. Opossums and snakes can even emit a fluid that produces a foul smell, thus adding to the pretense. Such behavior tricks predators into thinking that the animal is dead. Since most predators avoid dead or rotting animals, this type of defense mechanism is often very effective.

Trickery

Trickery can also be used as a formidable defense. False features that appear to be enormous eyes or appendages can serve to dissuade potential predators. Mimicking an animal that is dangerous to a predator is another effective means of avoiding being eaten. For example, some harmless snakes have bright warning colors that resemble the colors of dangerously venomous snakes. Warning calls can also be used by one animal species to trick another animal species. The African fork-tailed drongo bird has been known to mimic meerkat warning calls when meerkats are eating their prey. The alarm causes the meerkats to flee, leaving their abandoned meal for the drongo to finish.

Physical Features

Physical anatomical structures can also serve as a type of defense mechanism. Some animals' physical features make them very undesirable meals. Porcupines, for example, make a very difficult meal for predators because of their extremely sharp quills. Similarly, predators would have a tough time trying to get to a turtle through its protective shell.

Chemical Features

Chemical features can be just as effective at deterring predators. We all know the hazards of scaring a skunk! The chemicals released result in a not so pleasant aroma that an attacker will never forget. The dart frog also uses chemicals (poisons secreted from its skin) to deter attackers. Any animals that eat these small frogs are likely to get very sick or die.

Warning Calls

Some animals sound the alarm when danger approaches. For example, oxpeckers (birds that live in mutualistic relationships with grazing animals) will give a loud warning call when predators get too close. African elephants emit a rumbling alarm call when they hear the sound of African bees. Animals can also give distinctive calls to identify the type of threat. For instance, monkeys have one alarm sound for leopards and a different sound for eagles.

Predator-Prey Relationship

To sum it all up, the predator-prey relationship is important to maintaining balance among different animal species. Adaptations that are beneficial to prey, such as chemical and physical defenses, ensure that the species will survive. At the same time, predators must undergo certain adaptive changes to make finding and capturing prey less difficult.

Without predators, certain species of prey would drive other species to extinction through competition. Without prey, there would be no predators. The animal organisms in such an environment could become endangered or even extinct. The predator-prey relationship ensures that the cycle of nutrients in biomes continues. Thus, this relationship is vital to the existence of life as we know it.