Unit 9 vocab Flashcards
Evolution
The process of biological change by which decendants come to defer from their ancestors
Species
A group of organisms so similar to one another that they can reproduce and have fertile offspring.
Fossil
traces of an organisms that existed in the past.
Variation
The difference in the physical traits of an individual from those of other individuals in the group which it belongs to.
Adaption
A feature that allows an organism to better survive in its environment.
Artificial selection
The process by which humans change a species by breeding it for certain traits. Humans make use of the genetic variation in plants and animals by acting as the selective agent. They decide which traits are favorable and then breed individuals that show them.
Herditibility
The ability of a trait to be passed down from one generation to the next.
Natural selection
A mechanism by which individuals that have inherited beneficial adaptations produce more `
Fitness
A measure of the ability to survive and produce more offspring relative to other members of the population in a given environment.
Fitness
A measure to the ability to survive and produce more offpsring relative to toher members oin a population in a given enviroment.
Homologous Structure
Features that are similar in structure but appear in different organisms and have different functions.
Analogous Structures
Structures that perform a similar function but are not similar in origin.
Paleontology
The study of fossils or extinct organisms, continues to provide new information and support current hypotheses about how evolution occurs.
Gene Pool
Where genetic variation in a population is stored. The combined alleles of all the individuals in a population.
Allele frequency
A measure of how common a certain allele is in the population.
Gene flow
he movement of alleles from one population to another. This increases the genetic variation of the receiving population. However the less this occurs, the more genetically different the two populations become. The lack of it increases the chance that the two populations will evolve into different species.
Genetic drift
The change in allele frequencies that causes a loss of genetic diversity in a population.
Bottleneck effect
A genetic drift that occurs after an event greatly reduces the size of a population
Founder effect
A genetic drift that occurs after a small number of individuals colonize a new area. The gene pool of these populations are larger than others.
Sexual selection
Occurs when certain traits increase mating success. There are two types.
Specifiation
The rise of two more species from one existing species.
Convergent evolution
Evolution toward similar characteristics in unrelated species.
Divergent Evolution
When closely related species evolve in different directions and become increasingly different.
Coevolution
The process in which two or more species evolve in response to changes in each other.
Extinction
The elimination of a species from earth. Often occurs when a species as a whole is unable to adapt to a change in its environment.
Endosymbiosis
A relationship in which one organism lives within the body of another and both benefit from teh relationship.
Primate:
Category of mammals with flexible hands and feet, forward looking eyes-which allows for excellent three dimensional vision and enlarged brains relative to body size.
Hominid:
Walk upright, have long lower limbs, thumbs that oppose-or work against the other four fingers, relatively large brains.
Bipedal
Animals that can walk on 2 legs
Taxonomy
The science of naming and classifying organisms. Gives scientists a standard wat to refer speicies and organize the diversity of living things.
Binomial noemnclature
A system that gives each species a two part scientific name using Latin words.
genus
Includes one or more physically similar species that are thought to be closely related.
Cladistics
A classification based on common ancestry.
Derived character
The traits that can be used to figure out evolutionary relationship among a group of species are those that are shared by some species but are present in others.
Derived character
The traits that can be used to figure out evolutionary relationships among a group of species are those that are shared by some species but are not present in others.
