Biology Chapter 13-15, 36-38 Test

All life linked through a common ancestor; populations of living things change with time (evolve); the environment influences this change (natural selection) so that advantageous traits are selected over less advantageous ones, and the former become common in populations (descent with modification)

Trip around the world December 1831 22 year old naturalist, Charles Darwin set sail aboard the British naval vessel HMA Beagle
Primary mission was to expand the navy's knowledge of natural resources in foreign lands

Charles Lyell - geologist who proposed theory of uniformitarianism (gradualism); gave Darwin the time he needed for his theory.

Georges Cuvier - founded the science of paleontology, the study of fossils;
Hypothesized that whenever a new stratum showed new fossils, a local catastrophe has caused a mass extinction in that region.
After each catastrophe, the region was repopulated by species from surrounding areas, this is called

Offered the ideo of inheritance of acquired characteristics - traits that and organism acquired during its lifetime could be passed on to the offspring.

Those that are anatomically similar becasue they are inherited from a recent common ancestor; ex. Bone structure of foreleg of a horse & wing of a bat, may and may not have same function.

Those that serve the same function, but they are not constructed similarly, nor do they share a recent common ancestry ex. Insect wing & bird wing.

Fossils - Traces of past life, such as trails, footprints, burrows, worm casts, or preserved droppings; most fossils consist of hard parts, such as shells, bones, or teeth, because soft parts are usually consumed or destroyed.
Fossil record - The history of life recorded by fossils & the most direct evidence we have that evolution has occured.

Generation to generation changes in a population's frequency of alleles or genotypes.

Of a population is all the alleles in all the individuals making up a population.

The movement of alleles between populations.

A. No mutations - allele changes do not occur, or changes in one direction are balanced by change in the opposite direction.
b. No gene flow - Migration of alleles into or out of the population does not occur.
c. Random mating - The individuals pair by chance, not according to their genotypes of phenotypes.
d. No genetic drift - The population is very large, and changes in allele frequencies due to chance alone are insignificant.
e. No natural selection

When an intermediate phenotype is favored;
Ex. Human birth weight, clutch size in birds

When an extreme phenotype is favored & the distribution curve shift in that direction.
Ex. Guppies

Two or more extreme phenotypes are favored over any intermediate phenotype.
Ex. British land snails