Basics of natural selection

Define artificial selection

Breeding organisms selectively to increase the likelihood of the development of desirable traits

Micro evolution

Change in gene frequency

Macro evolution

Formation of new species, caused by micro evolution

Overproduction

More individuals are produced by an organism and population than can survive

Outline the process of natural selection

Lots of varying individuals produced (overproduction) - offspring inherit variations, not all survive (competition), useful (to fitness) variations increase (selection) and evolution occurs.

Genotype vs phenotype

Geno=genetic makeup, pheno = visible manifestation of genotype. Genotype + environment = phenotype

How can we increase fitness?

Indirectly- through genes increasing survival, directly- through genes increasing reproductive success

Randomly varying replicators

genetic mutations

Biological fitness

Reproductive success- not how many individuals you bang, how many surviving kids you have

Give an example that disproves Lamarckism

Cropped ears in dogs- individuals w/ cropped ears don’t produce offspring w/ cropped ears

Give an example of Darwin’s evidence for evolution

Mockingbirds in the Galapagos had appeared similar but were different species unique to their respective islands.

Give one example of evidence of evolution

Mammalian forelimbs being a homologous structure adapted to different mammals for their habitats- whales fins vs human hands

Homology

Development of similar traits in distinct species due to shared ancestory

Outline the ‘central dogma’

A combination of Darwinian and Mendelian evolutionary theory. Genotype produces new genotype and subsequent phenotype produces new genotype and subsequent phenotype… Phenotype does not determine genotype (this would be Lamarckian)