![]() ![]() This explanation talks about punctuated equilibrium as the result of one or a few mutations that cause large change. The species changes very rapidly over a few generations, then settles down again to a period of little change. Because these mutations are so different and so helpful to the survival of those that have them, the proportion of individuals in the population who have the mutation/trait and those who don't changes a lot over a very short period of time. ![]() Though mutations are often harmful, the mutations that result in punctuated equilibrium are very helpful to the individuals in their environments. Mutations are random changes in the DNA that are not inherited from the previous generation, but are passed on to generations that follow. There is a period of very little change, and then one or a few huge changes occur, often through mutations in the genes of a few individuals. In punctuated equilibrium, change comes in spurts. Change is slow, constant, and consistent. Very gradually, over a long time, the population changes. Small variations that fit an organism slightly better to its environment are selected for: a few more individuals with more of the helpful trait survive, and a few more with less of the helpful trait die. Over a short period of time it is hard to notice. Gradualism is selection and variation that happens more gradually. Scientists think that species with a shorter evolution evolved mostly by punctuated equilibrium, and those with a longer evolution evolved mostly by gradualism. A species can evolve by only one of these, or by both. Gradualism and punctuated equilibrium are two ways in which the evolution of a species can occur. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |