22 terms

Honors Biology Chapter 13

inherited characteristic that increases an organism's chance of survival
the gradual change in a species over time
artificial selection
selection by humans for breeding of useful traits from the natural variation among different organisms
natural selection
The process by which individuals that are better adapted to their environment are more likely to survive and reproduce than other members of the same species
disappearance of a species from all parts of its geographical range
scientist who studies fossils
fossil record
chronological collection of life's remains in sedimentary rock layers
layers of sedimentary rock
the study of the past and present distribution of species
similarity in characteristics resulting from a shared ancestry
homologous structures
similar structures that related species have inherited from a common ancestor
vestigial organs
organs that serve no useful purpose for the organism; these suggest that sometime in the past they were useful
evolutionary tree
a diagram that reflects evolutionary relationships among groups of organisms
group of individuals of the same species that live in the same area
gene pool
the combined genetic information of all members of a particular population
evolution resulting from small specific genetic changes that can lead to a new subspecies
a change in the sequence of DNA
stabilizing selection
intermediate forms are favored and extreme forms are eliminated
directional selection
occurs when natural selection favors one of the extreme variations of a trait
disruptive selection
natural selection that favors individuals with either extreme of a trait
sexual dimorphism
marked differences between the sexes in secondary sexual characteristics, which are not directly associated with reproduction
sexual selection
results from differences in traits affecting access to mates