Evolution Vocabulary Test

Natural Selection

Process of evolution that allows the organisms best suited to the environment to survive and pass the favourable traits on to the next generation.
occurs in populations not individuals
requires:
-variation in organisms in population
-characteristics responsible for variation must be hereditary
-more offspring must be produced than are necessary
-changes must occur in the environment

Speciation by macroevolution

Type of evolution resulting in the development of a new species

Outbreeding

Formation of stronger, healthier offspring by outbreeding by adding new alleles to the gene pool

Founder effect

loss of genetic variation that occurs when a new population is established by a small number of individuals from a larger population

Geographical isolation

Speciation occurring due to physical barriers preventing interbreeding

Adaptive radiation

Organism adapting to a changing environment so that it no longer resembles the parent species / the diversification of a group of organisms from a common ancestor into different forms in different ecological niches

Evolution

Speciation occurring due to physical barriers preventing interbreeding

Homologous Structures

Parts of an organism that are similar in structure, but perform different functions, resulting from divergent evolution and arising from a common ancestor

Speciation

Development of new species by evolutionary chnages due to genetic changes

Microevolution

Type of evolution resulting in increased variation at species level

Convergent evolution

Evolving of unrelated organisms developing similar adaptations to suit a common environment and have analogous structures

Analogus structures

different structures which perform similar functions

Species

Group of individuals of common ancestry, closely resembling each other, who can interbreed to produce fertile offspring

Biogeographic Distribution

Study of the distribution of living organisms, past and present

Gene Pool

all the alleles of a gene in a particular population

Divergent Evolution

evolution of organisms from a common ancestor which have adapted to changing environments to develop into a new species and have homologous structures

Embryology

similarities and differences in embryonic development

Comparative anatomy

comparison of structures that show a gradual change /modification of structures that have evolved along the same group line

Fossils

remains of a once living organism or traces of the activities of the organism that have been preserved into sedimentary rocks.

Mutations

Changes that occur in the DNA sequence that produces variation and results in different characteristics developing in a population

Jean-Baptiste Chevalier de Lamarck

-Use and disuse
-Inheritance of acquired characteristic

Genetic drift

Is the random changes in the (genetic) allele frequency in a small population due to a random event that may lead to speciation either by (bottleneck/founder effect)

Evidence for Evolution

-Fossil record
-Homology
-Comparative anatomy; Genetic similarities; Comparative embryology
-Biogeographic distribution
-Biochemical similarities

Punctuated Equilibrium

Short evolutionary bursts (phenotypic characteristics change) with periods of stability (equilibrium)

Gradualism

idea that continuous change at constant evolutionary pace

Vestigial Structures

parts or structures present in an organism do not have functional use due to organisms evolving and adapting

Selection pressure

Factors in the environment that will select/favour certain individuals based on particular characteristic

Artificial selection

process where specific organisms with specific traits are selected for breeding purposes to produce offspring with desires traits

Biological species

-similar DNA
-closely resemble each other
-interbreed and produce fertile and viable offspring

Allele frequency

represents the incidence of gene variant in a population.
alleles-number of times a particular gene appears in a population

Bottleneck effect

sharp reduction in the size of a population due to environmental/human events which lead to reduction in gene pool and the prevalence of a particular characteristic

Allopatric speciation

-formation of new species due to geographical/physical isolation of a few individuals
-form a new population and can no longer interbreed

Sympatric Speciation

-formation of a new species due to reproductive isolation

-pre-zygotic (occurs before fertilization and no offspring produced)
> temporal (two species mate at different times)
>ecological(two species occupy different habitats)
>behavioural(occurs when two species have different courtship behaviors/mating calls)
>mechanical(physical differences between species i.e. different sized dogs)

-post-zygotic(occurs after fertilization and offspring are not viable/fertile)
> hybrid inviability(hybrids don’t rewatch reproductive maturity)
>hybrid infertility( hybrids are sterile/infertile)
>hybrid breakdown( first gen hybrid are fertile but second gen may not be able to either reproduce/ survive)

Extant

refers to existence/living of a population/species

Inbreeding (naturally)

-reproduction occurs naturally within a small, isolated populations
-leads to gene frequency for a particular characteristic becoming more common in the population over time

Outbreeding (naturally)

-reproduction occurs naturally in larger populations that can freely interbreed and exchange genetic material
-leading to greater variation and genetic diversity

Gene Flow

-exchange of genetic material between larger populations
-inbreeding/outbreeding through migration
-happens through migration