chapter 13 - how populations evolve Flashcards
Evolution
the heritable changes in populations over generations that made diversity
creationism
god created life that means perfect no changes
George’s Buffon’s Theory
fossil species could be ancient versions on similar living species
Jean Baptiste Lamarck ( theory of inquiried characteristics)
Characteristics acquired due to environmental pressures
Charles Lyell ( theory of Uniformitarianism )
very slow and subtle processes cause substantial change
what are Darwin’s Observations
plants and animals in temps in American similar to tropical regions in souther continent
what are the 2 points on the origin of species
evolution is the basis of life’s diversity and natural selection cause of evolution
what are the 3 observation to prove natural selection as the mechanism for evolution
Overproduction, individual variation, adaption
what are the 3 inferences based on the 3 observations
struggle for existence, survival of the fittest, gradual change in the population
natural selection
differntial survival and reproduction of some individuals in population and death without issue of others
what are the requirements of natural selection
genetic variation, inheritance, resource competition, differential reproductive success
evidence of evolution
biogeography, fossil record, comparative anatomy, and molecular biology
Biogeography
study of the geographic distribution of species
fossil record
how species evolved from the found fossil
comparative anatomy
same anatomy and different function suggesting common ancestor
molecular biology
similarity genetic code
modern synthesis
fusion of genetics with evolutionary biology
what are the main points of modern synthesis
population is the smallest unit that can evolve, natural selection is the main mechanism for evolution, small changes accumulate over time bring lagging changes
Population Genetics
study of genetic variations in a population
how sexual recombination ?
meiosis, random fertilization
what bring genetic variation in population
sexual recombination, mutations
how do you track a population over time
analyzing gene pool(all alleles of all the individuals in population)
Hardy Weinberg Principle
allele frequencies of population in equilibrium remain constant from generation to generation
5 conditions for the HW Principle to hold true
must be large in size, isolated from other populations, no mutations, mating must be random, natural selection can’t take place
what are the 3 types if natural selection ?
Stabilizing , directional, disruptive
Stabilizing
when the average phenotype is favored more than extremes
directional
when the extreme pheontype is favored over the average
geneflow
introduction of genes in population due to migration of fertile individuals
genetic drift
change in allele frequenues of a population due to chance alone
what are the types of genetic drift
bottleneck and founder effect
bottleneck
dramatic reduction in genetic diversity of population resulting from an ecological crisis that wipes out most members
founder effect
establishment of a new population by very few individuals that migrate to a new environment
