Patterns and Methods of Evolution in Biology: Cladistics, Natural Selection, and Phylogenetics

What is the field of study that focuses on the evolution of species?

The field is called evolutionary biology.

What can phylogenetic trees be used for?

Phylogenetic trees can be used to infer the history of species evolution and describe past changes in genes, genomes, life histories, and development.

What are two patterns of evolution sometimes called?

Two patterns of evolution are sometimes called macroevolution and microevolution.

What is cladistics?

Cladistics is a classification system in which taxa are described as groups of species composed of a common ancestor and all of its descendants.

What are groups that do not include all descendants called?

These groups are called paraphyletic groups.

What are groups that do not include a common ancestor called?

These groups are called polyphyletic groups.

What characteristics are used to classify taxa?

Characteristics used to classify taxa include homologies, embryological similarities, vestigial characteristics, convergence, suboptimal design, geographic distribution, and intermediate forms.

What is adaptive radiation?

Adaptive radiation is the process in which organisms diversify rapidly into a wide variety of forms to adapt to different environments.

What is natural selection?

Natural selection is the process by which traits that enhance survival or reproduction become more common in a population.

What is a characteristic that enhances survival or reproduction called?

This characteristic is called an adaptation.

What is preadaptation?

Preadaptation is a feature that fortuitously serves a new function.

What is fitness in evolutionary terms?

Fitness is the reproductive success of a particular genotype in a population.

How is absolute fitness calculated?

Absolute fitness is calculated as the proportion of offspring that survive to reproduce multiplied by the average number of offspring produced.

What is relative fitness?

Relative fitness is the fitness of a genotype compared to the highest fitness genotype in the population.

What is the coefficient of selection?

The coefficient of selection is the amount by which fitness is reduced by selection relative to the reference genotype.

What does the selective advantage of a fitter genotype represent?

The selective advantage represents the increase in reproductive success of the fitter genotype compared to others.

What are the three general patterns of natural selection?

The three general patterns of natural selection are directional selection, stabilizing selection, and disruptive selection.

What is frequency-dependent selection?

Frequency-dependent selection is a type of selection where the fitness of a phenotype depends on its frequency relative to other phenotypes in the population.

What is the significance of the evolution of sex ratio?

The evolution of sex ratio tends to be frequency-dependent and is considered an evolutionarily stable strategy (ESS).

What is the role of mutations in natural selection?

Mutations can introduce new alleles into a population, some of which may confer a selective advantage.

What is the relationship between genetic change and relative fitness?

The rate of genetic change in a population depends on the relative fitness of the genotypes, not their absolute fitness.