Evolution 10/24/13

• Evolution is descent with modification
• Evolution implies biological evolution
• All life on earth shares a common ancestor
• Phylogeny is the evolutionary tree at which species evolve, and is a hypothesis on the relationships among organisms
• Moving through a phylogeny is moving through time
• A split represents a branching on phylogeny
• Each part of the phylogeny is specifically unique
• They are trees, not ladders
• Characteristics of the animals/species help with ordering them
• The species that is most important to the biologist goes on the right
• Homologous characteristics are those that are similar among species
• Bird and bat wings are analogous, which mean they have separate evolutionary origins, even though they look similar
• It is used for classifying organisms, as well
• Linnaean system: Kingdom, Phylum, Class, Order, Family, Genus, Species
• A clade is a group that shares a common ancestor
• The chart allows for easy distinguishing of relationships
• Humans are very young
• Radiometric dating relies on half life decay to discover the times at which things lived
• Stratigraphy uses other dates to estimate the time
• Molecular Clocks allow genetic divergence between organisms for time estimates
• Descent and the genetic differences that are heritable and passed on to the next generation;
• Mutation, migration (gene flow), genetic drift, and natural selection as mechanisms of change;
• The importance of genetic variation
• The random nature of genetic drift and the effects of a reduction in genetic variation;
• How variation, differential reproduction, and heredity result in evolution by natural selection; and
• How different species can affect each other's evolution through coevolution.
• Mutation is an unnatural, random change of genes
• Migration is when two different species of organisms interact
• Genetic drift is when a certain type of organism is diminished, and less of that organism's genes will be passed down
• Natural selection is survival of the fittest
• Fitness is how well an organism can leave offspring alive
• Sexual selection is the ability for an organism to find a mate, easily. Sometimes, organisms go to extreme lengths to find a mate. If is not successful, it will not pass on its genes
• Artificial selection is when humans are involved in the process of sexual selection
• Adaptation helps for organisms to survive
• No such thing as a "perfect organism."
• Coeveolution is when two organisms effect each others morphology
• Microevolution - evolution on a small scale
• A population is a species that interbreed with each other
• The same species can look different, and the different-looking organisms can interbreed
• Speciation event is the birth of a new species
• Isolation causes speciation
• Speciation can also be caused by a difference in mating rituals
• Lack of fit of genitals
• Cospeciation is when two organisms effect the speciatition of another organism
• Macroevolution is evolution on a grand scale
• It is involved in the tree of life
• 3.8 billion years is macro
• Many species find a stasis, from which they will not evolve much
• Lineages can change quickly or slowly
• Extinction plays a big part in macroevolution