Friedland APES Chapter 5

Ecosystem Diversity

the variety of ecosystems within a given region

Species Diversity

the variety of species within a given ecosystem

Genetic Diversity

the variety of genes within a given species

Species Richness

the number of species in a given area

Species Evenness

the relative proportion of different species in a given area

Phylogenies

the branching patterns of evolutionary relationships

Evolution

a change in the genetic composition of a population over time

Microevolution

evolution occurring below the species level

Macroevolution

evolution that gives rise to new species, genera, families, classes or phyla

Genotype:

the complete set of genes in an individual

Mutation

a random change in the genetic code produced by a mistake in the copying process

Recombination

process by which one chromosome breaks off and attaches to another chromosome during reproductive cell division

Phenotype

a set of traits expressed by an individual

Artificial Selection

a breeder chooses to perpetuate certain desirable inheritable traits in a plant or animal

Natural Selection

survival of a species due to it being most suited to the environment

Fitness

an individual's ability to survive and reproduce

Adaptation

a trait that improves an individual's fitness

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

Founder Effect

a change in a population descended from a small number of colonizing individuals

Geographic Isolation

physical separation of a group of individuals from others of the same species

Reproductive Isolation

two populations within a species evolving separately so they can no longer interbreed and produce viable offspring

Allopatric Speciation

the process of speciation that occurs with geographic isolation

Sympatric Speciation

the evolution of one species into two, without geographic isolation

Genetic Engineering

direct manipulation of genetic material in order to alter the hereditary traits of a cell, organism, or population

Genetically Modified Organisms

an organism produced by copying genes from a species with a desirable trait and inserting them into another species

Range of Tolerance

the limits to the abiotic conditions that a species can tolerate

Fundamental Niche

ideal environmental conditions for a species

Realized Niche

range of abiotic and biotic conditions under which a species actually lives

Distribution

areas of the world in which a species live

Niche Generalists

a species that can live under a wide range of abiotic or biotic conditions

Niche Specialists

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 a species in a relatively short period of time