Evolution Charles Darwin 1859 Darwin observed that organisms

Evolution

� Charles Darwin � 1859 Darwin observed that organisms in a population differ slightly form each other in form function, and behavior. Population is a group of the same species in the same place �Darwin proposed that the environment exerts a strong influence over which individuals survive to produce offspring. �Natural selection is the unequal survival and reproduction that results from the presence or absence of particular traits.

�Darwin proposed that over many generations natural selection causes the characteristics of populations to change. �Evolution is a change in the genetic characteristics of a population from one generation to the next.

Organisms produce more offspring than can survive. The environment is hostile and contains limited resources. Organisms differ in the traits they have. Some inherited traits provide organisms with an advantage. 1. 2. 3. 4. 1. 5. This is an adaption, which is an inherited trait that increases an organisms chance for survival Each generation contains proportionately more organisms with advantageous traits.

� Coevolution is the process of two species evolving in response to longterm interactions with each other.

� Many populations of plants and animals are cared for by humans. � People can control how domestic plants and animals reproduce thus, how they can evolve. �For example, the wolf is the ancestor to certain breeds of dogs which was caused by humans breeding wolfs with other dogs. � Artificial selection is the selective breeding of organisms by humans for specific characteristics

� Some animals or plants evolve due to unwanted adaptations �For example, some viruses are resistant to antibiotics or build a resistances to antibiotics. � Resistance is the ability of one or more organisms to tolerate a particular chemical designed to kill it. � Humans promote the evolution of resistance when they try to kill pest or plants

� Do you think humans can evolve again?