Chapter 15

Genetic drift is the random change in allelic frequencies in a population, different from natural selection, gene flow, and mutation.

Disruptive selection is a type of natural selection that favors extreme traits over average traits. Stabilizing selection, on the other hand, favors the average traits. Directional selection favors one extreme trait over the other. Genetic drift is a random process that can lead to changes in allele frequencies within a population.

Stabilizing selection is a type of natural selection that favors the intermediate variants of a trait, while directional selection favors one extreme and disruptive selection favors both extremes. Artificial selection is a process where humans intentionally breed organisms with desirable traits, not a form of natural selection.

The founder effect is a type of genetic drift that occurs when a small group from a larger population establishes a new isolated population.

Sympatric speciation occurs when new species evolve from a single ancestral species without any physical barriers separating the populations. Allopatric speciation occurs when a physical barrier divides a population, parapatric speciation occurs when populations are separated by an environmental gradient, and peripatric speciation occurs when a small group of individuals colonize a new isolated habitat.

Directional selection is the process in which a certain extreme trait value becomes more advantageous to the population over time. Stabilizing selection maintains the status quo, disruptive selection favors extreme trait values at both ends of the spectrum, and sexual selection is based on mating preferences.

Allopatric speciation is a process that occurs when a population becomes geographically isolated, leading to the formation of new species. This differs from sympatric speciation, parapatric speciation, and peripatric speciation, which involve different mechanisms for speciation.

Sexual selection refers to the process by which characteristics that increase an individual's ability to secure a mate are passed on to the next generation. It is different from natural selection, genetic mutation, and environmental adaptation.

Adaptive radiation is a process where one species diversifies into multiple species in a relatively short time due to various environmental pressures and opportunities.

Gradualism is the theory that evolution occurs slowly and steadily over long periods of time. Punctuated equilibrium suggests that evolution happens in sudden bursts separated by long periods of stability. Catastrophism is the idea that geological change happens suddenly due to catastrophes. Phyletic gradualism is a term previously used to describe the idea of gradual evolution within a single lineage.

The Hardy-Weinberg principle states that allele frequencies in a population will remain constant from generation to generation in the absence of other evolutionary influences.

The founder effect is a phenomenon where a small group within a population establishes a new population and changes in allele frequencies occur due to random sampling in the founders. Genetic drift is the random changes in allele frequencies in a population. Adaptive radiation is the diversification of a group of organisms into forms filling different ecological niches. Allopatric speciation is the formation of new species due to geographic isolation.

Genetic drift is a random change in allele frequencies in a population, different from natural selection which is based on the fitness of alleles, genetic mutation which is the alteration of DNA sequence, and gene flow which is the transfer of genetic material between populations.

Directional selection occurs when an extreme phenotype is favored, causing the allele frequency to shift over time towards that extreme trait. Stabilizing selection maintains the status quo, disruptive selection increases genetic diversity, and sexual selection involves traits that improve mating success.

Disruptive selection is the process by which individuals with extreme traits are favored over those with average traits, leading to the removal of individuals with average traits from the population.

Alleles are different versions of a gene that can lead to different traits or characteristics in an organism. Genes are the basic unit of heredity, chromosomes are structures that carry genetic information, and mutations are changes in the DNA sequence that can result in different traits.

Natural selection is the process by which organisms better adapted to their environment tend to survive and produce more offspring. It is the key mechanism of evolution.

Evolution is the process by which different kinds of living organisms are thought to have developed and diversified from earlier forms during the history of the Earth.

Derived traits are characteristics that are newly evolved and unique to a particular group of organisms, distinguishing them from their common ancestors.

An ancestral trait refers to features that are shared due to common ancestry, reflecting evolutionary relationships.

Homologous structures are anatomically similar structures that are derived from a common ancestor. Analogous structures are similar in function but not in structure, vestigial structures are remnants of structures that were functional in ancestral species, and convergent structures are similar in function but evolved independently.

Vestigial structures are anatomical features that have lost their original function through evolution. They are remnants of structures that were functional in ancestral species.

Analogous structures refer to structures in different species that have the same function but were not inherited from a common ancestor. Homologous structures are structures that are similar in origin but may have different functions. Convergent structures are similar structures that evolve independently in different species. Parallel structures are structures that have similar construction and function because they were inherited from a common ancestor.

Biogeography is the study of the geographical distribution of biological organisms.

The incorrect answers provided have no scientific basis or evidence to support the theory of evolution.

The fossil record is a valuable resource for studying the history of life on Earth, showing the evolution of species over time. Transitional fossils provide evidence of organisms with features of both older and more recent species, such as birds with dinosaur characteristics, helping to document the process of evolution.

In comparative anatomy, structures are classified as homologous if they share a common ancestor, vestigial if they have lost some or all of their original function, and analogous if they serve the same function but do not have a common evolutionary origin.

Embryonic evidence in vertebrates shows that despite differences in adult forms, there are shared features in embryos that point to a common ancestor. This supports the theory of evolution and the idea that vertebrates evolved from a common source.

Hox genes play a crucial role in determining the overall body plan of an organism by influencing the differentiation and development of cells in specific body regions.

Homeobox genes play a crucial role in determining the body plan of an organism by controlling the identity of body parts during early embryonic development. They are distinct from other types of genes mentioned in the incorrect answers.