Evolution
This term refers to the change in the genetic composition of a population during successive generations, which may result in the development of new species.
What is evolution?
The term for the movement of genes from one population to another due to migration or mating.
What is gene flow?
It is the variation of allele frequencies at or above the level of species over geological time, resulting in the divergence of taxonomic groups, in which the descendant is in a different taxonomic group to the ancestor.
What is macroevolution?
The term used to describe small-scale variation of allele frequencies within a species or population, in which the descendant is of the same taxonomic group as the ancestor.
What is microevolution?
Type of speciation that involves divergence of species within the same geographical location (i.e. without a physical barrier).
Who is sympatric speciation?
This phenomenon refers to the disappearance of a large number of species within a relatively short period of time.
What is a mass extinction?
This process introduces new alleles into a population and is the ultimate source of genetic variation.
What is mutation?
The term for the pattern of speciation where populations become more dissimilar over time due to different selection pressures. Homologous structures are present.
What is divergent evolution?
Diagram that helps to graphically represent the relatedness that exist between organisms
What is a cladogram?
This type of selection favours individuals with traits that are at one extreme of a range of variation.
What is directional selection?
The degree of DNA similarity can be used to infer this type of relationship between species.
What is a phylogenetic relationship?
This type of selection favours individuals with traits that are in the middle of a range of variation.
What is stabilising selection?
This mode of speciation occurs when populations are physically isolated from each other by geographic barriers.
What is allopatric speciation?
Occurs when a mutation in an allele provides a new trait that opens up new opportunities for subgroups within the species OR because of mass extinctions opening up previously occupied niches.
What is evolutionary radiation?
This process involves random changes in allele frequencies within a population, often more pronounced in smaller populations.
What is genetic drift?
Involves comparing genomes between species to determine evolutionary relationships.
What is comparative genomics?
1. directional
2. Stabiliing
3. Disruptive
What are the 3 types of phenotypic selection?
The term for a sharp reduction in the size of a population, leading to reduced genetic diversity.
What is a population bottleneck?
It is a term used when a gene has remained essentially unchanged throughout the evolutionary history of a species.
What is a conserved gene?
The process by which species adapt to their environment through the accumulation of advantageous traits.
What is natural selection?
This phenomenon refers to the evolution of species in response to changes in each other. Usually animals in a symbiotic relationship.
What is coevolution?
The founder effect occurs when a small group breaks away from a larger population to colonise a new territory. This small population subset has lower genetic diversity than the main population
What is the founder effect?
When two or more distantly related species adopt similar adaptations (behavioural, structural or physiological) in response to overcome common environmental pressures.
What is convergent evolution?
A scaled cladogram.
What is a phylogram?
1. Variation in the population
2. application of a selection pressure
3. Individuals with favourable characteristics are able to interbreed and produce fertile offspring
4. Favourable allele increases in frequency in the population.
What are the four steps of natural selection?