Predators are animals that kill for their food; they must do this in order to survive. There has been controversy about predation in some areas including the re-introduction of wolves into the Yellowstone National park area and other areas. Predator-prey relationships are both beneficial and detrimental to some species. The weakest and unhealthiest become dinner for those predators and also become a positive thing for the species that only the strongest of the herd will survive and continue to reproduce. Some types of prey have defense mechanisms which fight off predators. Survival of the fittest is the best explained phrase for this type of ecological interaction.
Predator-prey relationships are a common interaction found in every type of ecosystems and communities. A predator is an organism that kills for their food. They must kill in order to survive. The prey is the organism being killed for food. Predation is an interaction where it is a +/- interaction. This could be related to animals killing animals, but the same concept is in other interactions such as bear eating berries or other insects eating leaves. If the predator doesn’t eat, it dies. Throughout the years, with evolution, animals have adapted to become better predators and prey has become harder targets. Predator-prey relationships are unstable. I will explain more about this throughout this essay in different species in different types of ecosystems, and the impacts of this type of interaction.
Predator/Prey Interaction and Evolution
Predator-prey relationships are a +/- interaction. The prey is killed and the predator gains energy and nutrients. Predators are the primary movers of energy throughout the food web. When prey is abundant, predator population increases. It is a cycle that is continuous. When prey numbers decline, the predators also decline, therefore the cycle rebuilds itself. If the prey population of the primary choice of predators declines, they learn to move on to another species of prey to suffice their needs. When this runs out, they are forced to leave the area, the primary choice of prey population will then recover, and the predators will eventually come back to the area. There are positive and negative effects of this type of interaction in all ecosystems and throughout time, predators and prey have evolved in different ways. Throughout evolution, predators have evolved in ways that make them better hunters. They have become faster runners, so they can chase and capture their prey. Predators have a very keen sense of smell, sight and hearing so they can target the unhealthy and the weak prey for their food. Animals that are prey to predators have also a keen sense of smell and hearing so they can avoid becoming dinner. Some species have ways of camouflaging themselves to be less visible to their predators. For example, the snowshoe hare is white and has a better chance of blending in with its environment, in the snow, so the chances may be slightly less for being consumed by a predator. Other adaptations that have evolved in predators throughout the years were predators becoming better runners to chase their dinners. Some predators can run up to 70 mph, the cheetah of course, which helps for catching their prey. But other predators can run up to 40 mph as well. They also have great stamina for long periods of searching for food; they can travel for longer periods of time and scout out wider territories. (Phillips and Smith, 1996) Predators can be predators and prey to something else as well. There are many predators that aren’t on the top of the food web, and they can be prey themselves. A spider could be on a web consuming an insect lunch. A lizard could have its tongue ready to strike and slurp up the spider; meanwhile there is a roadrunner behind the lizard, ready for a snack. And an hour later a coyote preys on the roadrunner. This...
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