APES Chapter 5
Evolution of Biodiversity
Terms in this set (43)
Ecosystem Diversity (Biodiversity Level 1)
The variety of ecosystems within a given area.
Species Diversity (Biodiversity Level 2)
The variety of species within a given ecosystem. (Most common)
Genetic Diversity (Biodiversity Level 3)
The variety of genes within a given species.
Physical locations on chromosomes within each cell of an organism. The blueprint for an organism's traits.
A group of organisms that is distinct from other such groups in terms of size, shape, behavior, or biochemical properties, and that can interbreed with other individuals in the group to produce viable offspring.
The number of species in a given area.
Tells whether or not a particular ecosystem is numerically dominated by one species of whether all of its species have similar abundances.
High Species Evenness
All species are all represented by similar numbers of individuals.
Low Species Evenness
If one species is represented by few individuals and there is less diversity.
The branching patterns of evolutionary relationships. Determined by the similarity of their traits.
Equation that measures species diversity.
A change in the genetic composition of a population over time. Depends on genetic diversity.
Evolution below the species level. (ie. apples, potatoes)
When genetic changes give rise to new species, or to new genera, families, classes, of phylums.
The complete set of genes in an individual.
Mutation (Genetic Diversity)
DNA copies millions of cells in an organisms lifetime as cells grow and divide. An occasional mistake in this process produces a random change.
Recombination (Genetic Diversity)
Occurs as chromosomes are duplicated during reproductive cell division and a piece of one chromosome breaks off and attaches to another chromosome. Doesn't create new genes, but rather brings together new combinations of genes, and therefore new traits.
The actual set of traits expressed in an individual. (Anatomy, physiology, behavior)
Evolution by Artificial Selection
When humans determine which individuals breed, typically with a preconceived set of traits in mind.
Evolution by Natural Selection
The environment determines which individuals survive and reproduce.
Darwin's Theory of Evolution by Natural Slection
-Individuals produce an excess of offspring.
-Not all offspring can survive.
-Individuals differ in their traits.
-Difference in traits can be passed on from parents to offspring.
-Differences in traits are associated with differences in the ability to survive and reproduce.
An individual's ability to survive and reproduce.
Traits that improve an individual's fitness.
Evolution by Random Processes
Mutation, genetic drift, bottleneck effect, founder effect.
A change in the genetic composition of a population over time as a result of random mating.
A reduction in the genetic diversity of a population caused by a reduction in its size. (Low genetic variation is bad, causes increased risk of disease and low fertility)
A change in a population descended from a small number of colonizing individuals.
The colonization of a new area or habitat separated from the rest of the population.
So different, can no longer interbreed to produce viable offspring.
Requires geographic isolation, can no longer interbreed because they have become so different.
The evolution of one species into two species in the absence of geographic isolation. (Polyploid)
Most organisms have two sets of chromosomes.
The Pace of Evolution
3 million years to evolve. Factors include: rate of environmental change, genetic variation, population size, and generation time.
Techniques with which a scientist can copy genes from a species with some desirable trait.
Genetically Modified Organisms
Scientist can genetically insert genetically engineered genes into other species.
Range of Tolerance
Limits to the abiotic conditions that a species can tolerate. (Temperature, humidity, salinity, pH)
The suite of ideal conditions in an area for a species.
The range of abiotic and biotic conditions under which a species actually lives in.
The areas of the world in which the species lives.
Organisms that can live in a variety of habitats or feed on a wide variety of organisms.
Organisms that can only feed off of specific things or live in specific habitats.
The remains of organisms that have been preserved in rocks.
Five periods have been revealed during which large numbers of species went extinct over relatively short periods of time.