Chap 5: Definitions 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
A change in the 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
A random change in the genetic code produced by a mistake in the copying process.
RECOMBINATION
The genetic process by which one chromosome breaks off and attaches to another chromosome during reproductive cell division.
EVOLUTION BY ARTIFICIAL SELECTION
The process in which humans determine which individuals breed, typically with a preconceived set of traits in mind.
EVOLUTION BY NATURAL SELECTION
The process in which the environment determines which individuals survive and reproduce.
FITNESS
An individual’s ability to survive and reproduce.
ADAPTATION
A trait that improves an individuals fitness.
GENE FLOW
The 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 it’s size.
EXTINCTION
The death of the last member of a 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
The process of speciation that occurs with geographic isolation.
REPRODUCTIVE ISOLATION
The result of two populations within a species evolving separately to the point that they can no longer interbreed and produce viable offspring.
SYMPATRIC SPECIATION
The evolution of one species into two, without geographic isolation.
GMO: GENETICALLY MODIFIED ORGANISM
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.
Abiotic condition include: temperature, humidity, salinity and pH.
FUNDAMENTAL NICHE
The suite of abiotic conditions under which a species can survive, grow, and reproduce.
REALIZED NICHE
The range of abiotic and biotic conditions under which a species actually lives.
exemple of biotic condition include presence of competitors, predators and diseases.
DISTRIBUTION
Areas of the world in which a species lives.
NICHE GENERALIST
A species that can live under a wide range of abiotic of biotic conditions.
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.
