chapter 5 Flashcards
species richness
the number of species in a given area
species evenness
the relative proportion of individuals within the different species in a given area
phylogeny
the branching pattern of evolutionary relationships
evolution
change in genetic composition of a population over time
microevolution
evolution below the species level
macroevolution
evolution that gives rise to new species, genera, families, classes, or phyla
gene
a physical location on the chromosomes within each cell of an organism
genotype
the complete set of genes in an individual
phenotype
a set of traits expressed by an individual
mutation
random change in genetic code
recombination
genetic process by which one chromosome during reproductive cell division
evolution by artificial selection
the process in which humans determine which individuals breed typically with certain traits in mind
evolution by natural selection
the process in which the environment determines which individuals survive
fitness
individuals ability to survive and reproduce
adaptation
trait that improves an individuals fitness
gene flow
process by which individuals move from one population to another and thereby alter the genetic composition of both populations
genetic drift
a change in the genetic composition of a population over time as a result of random mating
bottleneck effect
a reduction in the genetic diversity of a population caused by a reduction in its size
extinction
death of last member of species
founder effect
a change in the genetic composition of a population as a result of descending from a small number of colonizing individuals
geographic isolation
physical separation of a group of individuals from others of the same species
allopatric speciation
speciation caused by geographic isolation
reproductive isolation
the result if two populations within a species evolving separately to the point that they can no longer interbreed
sympatric speciation
evolution of one species into two without geographic isolation
GMO
organism modified by the genes of another species that has a desired trait
range of tolerance
the limits to the abiotic conditions that a species can tolerate
fundamental niche
the suite of abiotic conditions under which a species can survive grow and reproduce
realized niche
range of abiotic and biotic conditions under which a species actually lives
distribution
areas of the world in which a species lives
niche specialist
a species that is specialized to live in a specific habitat or to feed on a small group of species
mass extinction
a large extinction of species in a relatively short period of time
niche generalist
a species that can live under a wide range of abiotic or biotic conditions
