Microevolution

Microevolution - Microevolution Microevolution Definition...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Microevolution Microevolution Definition Microevolution Microevolution: small changes in a species over time. Example: bacterial resistance to antibiotics. Main Concept of Microevolution Main 1. You must have genetic variation. 2. You have environmental change. 3. A combination of forces will cause change. Other Key Concepts Other 4. These forces include: isolation, migration, natural selection and mutation. 5. These factors will form a slow change of gene frequencies over time. What give us Genetic Variation What Mutation: Change in an organisms DNA. Gene Shuffling: Mixing of genes during the process of reproduction. Mutation Mutation DNA DNA New Organism=New Traits New Traits of Mom Traits of Dad B blood A blood No widows peak Widows Peak Tongue Roller Tongue Roller Brown Eyes Blue Eyes Black Hair Blonde Hair Junior Junior AB blood No Widows Peak Non Tongue Roller Hazel Eyes Brown Hair Genetic Frequency Genetic How often a particular trait shows up in a particular population. Usually done by percentage. Peppered Moth Peppered Peppered Moth Peppered Peppered Moth Genetic Frequency Peppered Year % of Light Moths % of Dark Moths 1 90 10 2 83 17 3 71 29 4 64 36 5 48 52 6 39 61 7 33 67 8 22 78 9 12 88 10 8 92 Natural Selection Natural “Survival of the Fittest” Organisms with genes that are suited for their environment survive and pass them on. Organisms with genes that are not suited for their environment die out and do not pass them on. Genetic Drift Genetic Only take place in small populations. Some traits will be randomly passed more then others therefore showing up more often within a population. Migration Migration Movement of individuals in or out of a population. * Brings in new traits and genes. * Makes organisms adapt to new environments. Isolation Isolation A barrier forms between members of a population not allowing them to mate. * Could be physical, temporal (reproduce at different times) or behavioral. Meadowlarks Meadowlarks Eastern Western Islands Islands Island Canyon Orchids Orchids Mutations Mutations Add new traits into a population. If those new traits are helpful then they will be kept in that population and passed on. ...
View Full Document

Ask a homework question - tutors are online