Topic 10 Flashcards
Coevolution
is a type of selective force on 2 or more populations or species that interact so closely that simultaneous develop adaptations
Convergent evolution
is the independent development of similar structures in organisms that are not directly related; often found in organisms living in similar environments
Evolutionary Adaptations
is a type of adaptation that allows organism to match the changes happening to their environment
Which of the following would be considered an example of analogous structures?
wings of a bird, and of a butterfly
Homologous structures are which of the following?
are physical features in organism that share a common ancestor, but serve completely different functions
Vestigial Structures
are structures that have no apparent function, but resemble structures that ancestors of those species possessed
Analogous structures are which of the following?
structures of similar function, but different evolutionary origin
Artificial Selection
are changes in the genetic structures of populations/species due to selective breeding/intervention by humans
Natural Selection
is a type of selection caused by factors in the environment, leading to evolutionary changes, by differential reproduction of genotypes
Isotopic dating, measures the ratio of what in samples?
amounts of unstable isotopes
Define and Evolution, Evolutionary adaptations and Fitness?
evolution - refers to the genetic changes experienced by populations of organisms and can occur from any process that causes a change in the genetic composition of a population
Evolutionary adaptations – allows organisms to match the changes happening to their environment
Fitness -refers to the relative ability of an organism to survive and reproduce successfully in its environment. It is a central concept in evolutionary theory and is used to describe how well an organism is adapted to its environment. Fitness is usually measured by the number of offspring an organism produces that survive to reproduce themselves. The more offspring an organism produces that survive to reproduce, the higher its fitness
Define and list the five agents of evolutionary change?
Mutation -permanent changes in a cell’s DNA; includes changes in nucleotide sequence, alteration of gene position, gene loss or duplication, and insertion of foreign sequences. the ultimate source of genetic variation. Occurs so rarely that mutation alone usually does not change allele frequency much.
Gene Flow - the movement of alleles from one population to another. Individuals or gametes move from one population to another
Nonrandom Mating - individuals with certain genotypes sometimes mating with one another more commonly than would be expected on a random basis. Inbreeding is a common form of nonrandom mating, it doesn’t alter allele frequency but reduces the proportion of heterozygotes.
Genetic Drift -is the random fluctuation in allele frequencies over time by chance. The smaller the population, the more likely genetic drift to occur, as the greater the change is in allele frequencies from generation to generation. The larger the population, the more diversity is allowed to persist in the population. Ex. Founder effect, and Bottleneck effect
Natural Selection -is the differential reproduction of genotypes; caused by factors in the environment, that leads to evolutionary changes. Natural selection results from differential reproductive success. Darwin Suggested that natural selection was the process that caused Evolutionary adaptations. The only agent that adaptive evolutionary changes.
Define and list the differences between Natural Selection and Artificial Selection?
Natural Selection – is the differential reproduction of genotypes; caused by factors in the environment, that leads to evolutionary changes. Controlled by nature and increases chance of survival. Is performed on all types of organisms.
Artificial selection – changes in the genetic structures of populations due to selective breeding by humans. Controlled by humans is performed the desired organism of the human.
Defined and list the conditions that must be met in order for Evolution to occur by Natural selection?
- Phenotypic variation must exist among individuals in a population.
- Variation among individuals must result in differences in the number of offspring surviving in the next generation.
- Phenotypic variation must have a genetic basis.
Genetic variation
refers to the different alleles of genes found within individuals of a population.
Evolution
refers to the genetic changes experienced by populations of organisms and can occur from any process that causes a change in the genetic composition of a population
Population genetics
Population genetics and Allele frequencies, can be used to measure evolution occurring
is the study of the properties of genes in a population, as different populations have variation in the genes that exist
Mutation
are permanent changes in a cell’s DNA; includes changes in nucleotide sequence, alteration of gene position, gene loss or duplication, and insertion of foreign sequences
Mutations are the ultimate source of genetic variation, but they do not occur more frequently in situations that favor them by natural selection, and particular mutations do not occur by natural selection.
one of the evolutionary adaptations
Gene Flow
is the movement of alleles from one population to another
one of the evolutionary adaptations
Genetic Drift,
is the random fluctuation in allele frequencies over time by chance.
The smaller the population, the more likely genetic drift to occur, as the greater the change is in allele frequencies from generation to generation.
The larger the population, the more diversity is allowed to persist in the population.
ex. Founder effect, and Bottleneck effect
one of the evolutionary adaptations
Bottleneck effect,
loss of genetic variation
example of genetic drift
occurs when the population is drastically reduced in size, due to natural forces like flooding, drought, epidemic disease, which only allows a few surviving individuals to constitute a random genetic sample of the original population
Founder effect,
loss of genetic variation
example of genetic drift
occurs when a new population is formed from a single or a few individuals moving into an isolated area, which can make a previously rare alleles a significant fraction of the new population
Non-random mating,
individuals with certain genotypes sometimes mating with one another more commonly than would be expected on a random basis.
assortative mating,
a type of nonrandom mating in which phenotypically similar individuals mate more frequently.
disassortative mating,
a type of nonrandom mating in which phenotypically different individuals mate more frequently
selection
NATURAL SELECTION
one of the evolutionary adaptations
is the differential reproduction of genotypes; caused by factors in the environment, that leads to evolutionary changes
Darwin Suggested that natural selection was the process that caused Evolutionary adaptations.
Natural selection results from differential reproductive success.Individuals with best adaptations pass on those advantages on to offsprings, and then those adaptations become more common
ARTIFICIAL SELECTION
changes in the genetic structures of populations due to selective breeding by humans.
fitness
Fitness is the number of surviving offspring left in the next generation and is a measure of how many offspring survive.
Fitness consists of many components, a combination of survival, mating success, and number of offspring per mating.
