Please enable JavaScript.
Coggle requires JavaScript to display documents.
How do organisms evolve? - Coggle Diagram
How do organisms evolve?
-
Evidence of Evolution
Biogeography - The global distribution of organisms and the unique features of island species reflect evolution
and geological change
Embryology – understand how comparing embryo development in vertebrates shows patterns of development
from common ancestors
-
Anatomy – compare/contrast homologous and analogous structures, know examples of each as well as vestigial
structures.
Direct observation - We can directly observe small-scale evolution in organisms with short lifecycles (e.g.,
pesticide-resistant insects)
Fossil record – know examples and how it can be used to support evolution and be able to tell relative age of
fossils using rock strata
Mechanisms of Evolution
Mutations (middle finger)- changes in genetic code can cause a change in a gene, and this in turn can cause a change in how a protein functions. The change in protein function can affect the survival of the individual, which can change the frequency of the gene in the gene pool.
Gene flow from emigration/immigration ( pointer finger)- when there is significant flow of new arrivals or a
great number of departures from a population, the gene frequency in the gene pool is affected.
Adaptations- advantageous traits or behavior that allow an organism to live, while organisms with
disadvantageous traits will die out.
Small population size (pinky finger)- a population can shrink or a small population in general can have a smaller
gene pool. This is known as the founder effect or a genetic bottleneck.
Nonrandom mating (ring finger)- choosing a mate based on a particular trait can change the gene frequency in a population. This can cause one phenotype to be preferred over another, can cause one phenotype to become prevalent, while another one dies out.
Darwin and Wallace
(1) more individuals are produced than can survive; (2) there is therefore a struggle for existence; (3) individuals within a species show variation; and (4) offspring tend to inherit their parents' characters. If an animal has some trait that helps it to withstand the elements or to breed more successfully, it may leave more offspring behind than others. On average, the trait will become more common in the following generation, and the generation after that.
-
-
-