Natural Selection
what is natural Selection and its role in evolution?
Natural selection is the process by which the organisms best adapted to their environment survive and pass their traits to the next generation. So who ever has the best adaptation will live and reproduce. For example, the picture above has brown and green beetles. The bird is the predator. What color beetle do you think the bird will notice first? The bird will obviously notice the green beetles first because it is more noticeable. So in this case the brown beetles will live long enough to pass down its traits to the next generation. Natural selections role in evolution is that if natural selection never happened it will cause more competition and the food source will be low then the animals will die from hunger or cannibalism, then evolution will no longer happen. This is a process leading to evolution.
Overproduction
Overproduction is when living things produce more offspring that can survive, that leads to struggle for survival. When a organism overproduces only the most adapted are able to survive. For example fishes, most fishes lays 2,500 eggs or more. But only a proportion of those eggs hatch. And only few of those hatched fish grow to be adults, Plus only couple live long enough to reproduce. Which fishes are the ones who are able to reproduce? If you said the ones that are most adapted to its environment, then you are correct. Overproductions role in evolution is that if overproductions wasn't real and those 2,500 eggs hatch and live long enough to reproduce, then there will be less food for the whole species and natural selection wouldn't take place. So in a matter of time all of the fishes would end up dying.
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Genetic Variation
Each individual of species has a unique combination of traits or gene. Some are better suited for their habitat than others are. Plus, if the species has a high genetic variation, then they are more likely to adapt to more environments. And if the species has a low genetic variation, then they are less likely to adapt to other environments. For example, cheetahs has low genetic variation because all of them look the same, so they have a less chance adapting to other environments. Genetic Variation's role in evolution is that if the species have a good variation, then they will live long enough to reproduce and pass down traits.
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Mutation
Mutation mistakes in DNA replication. This is the source of new traits and accounts for increased variation. Some mutations are beneficial and some are not. Most of the time is not. But it all depends on the environment the organism lives in. For example the grass hopper that's pink is a disadvantage and its mutation won't last as long because birds would easily spot it and eat it. Same goes for the white lion. Its harder for it to stalk its prey because the prey could also easily spot it and runaway. Mutation role in evolution is that without mutation, new traits wouldn't form and genetic variation wouldn't take place. Causing the species to have low genetic variation that means it less likely to adapt to different environment.
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differential Survival
Organisms must compete against organisms of the same species for food and shelter, as well as avoid disease and predators. Only some organism survive adulthood. This is all about the survival of the fittest. Who ever has the best adaption will live on to adulthood. For example, the two bucks to the right are fighting, and whoever wins gets the deer to mate and pass down its trait. And who do you think will win? If you said the one that is most fit, then you are right. Its role in evolution is just another part of Natural Selection. It is practically natural selection paraphrased.
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