We have been making models all year. Why do we need to study predator-prey models? Animals eat other animals, its nature isn't it? Predators and prey can influence one another's evolution. Remember, if you are prey and you are eaten, then you don't get to pass your DNA on to the next generation. But if you are prey that knows how to use skills that keep you alive, those DNA skills will pass on to the next generation. If you are a predator that lacks skills hunting...well, you starve to death and those lack-of-skills DNA are not passed on. But the stealthy hunter, the guy with all the moves, he gets his man and those healthy, stealthy genes are passed on to his youngsters. Scientists call this "selective pressures". A famous example of selective pressures in a population is the long neck and long legs on a giraffe. Possibly because food sources on the ground became scarce, the giraffe that could reach the upper levels of a tree or bush were the survivors. Those giraffe that were too short starved to death. The giraffe with long necks produced babies with long necks and after a period of generations more long necked giraffes survived, than short necked giraffes. Another example is bacteria. In the early 1900's bacteria was easily killed using simple antibiotics. These drugs were used to destroy the coating around the bacteria, and essentially the bacteria exploded and was destroyed. Well, some people didn't take their antibiotics to the very end like they were supposed to and the bacteria learned how battle against the antibiotic. Today we have to have stronger antibiotics to fight against bad bacteria...and the bad bacteria are winning... There are many examples of how the predator prey model works to help scientists understand how species that fight for different resources are able to adapt and change over time. This predator prey graph shows the study of the predator (Lynx) and the prey (Hare). Analyzing the graph you can see that the Hare is always just one step ahead of the Lynx. Scientists are very interested in discovering why this happens and get to the nitty gritty about the relationships between predators and prey.
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Mrs. TaylorI love science! Everything about the world is interesting and never boring. I love to study plants, animals, insects, and people. My favorite subjects are my students who are the most unique organisms on the planet! Categories |