Evolution Vocab

Carolus Linneaus

Created binomial nomenclature

Taxonomy

how species are classified

Bionomial nomenclature

two part name for each species

Georges Cuvier

Largely developed paleontology, advocated catastrophism

Catastrophism

geologic changes occur suddenly.

Charles Lyell

uniformitarianism: same geological processes that are at work today slowly formed the earth's surface

Uniformitarianism

geologic processes that occurred in the past can be explained by current geologic processes.

Jean-Baptiste Lamarck

Developed use and disuse and the inheritance of traits.

Malthus

Looked at human population and effect of poverty.

Wallace

"Struggle for existence" theory, weakest die off

Use and Disuse

parts of body used get stronger, parts that aren’t used deteriorate

Inheritance of acquired characteristics

organisms' bodies change during their lifetimes by use and disuse, these changes are inherited by their offspring.

Charles Darwin

formulated theory of evolution by natural selection.

Natural Selection

individuals that have certain inherited traits survive and reproduce more than others

Adaptations

Changes that allow an organism or species to survive and reproduce

Artificial Selection

Breeding organisms with specific traits in order to produce offspring with identical traits.

Populations

Groups of individuals that belong to the same species and live in the same area.

Paleontology

study of fossils

Homology

similar characteristics because of shared ancestry

Homologous structures

Structures in different species that are similar because of common ancestry.

Embryonic homologies

Similar structures in embryos

Vestigial structures

A structure that is present in an organism but no longer has a purpose

Molecular homologies

Shared characteristics on the molecular level

Convergent Evolution

unrelated organisms independently evolve similarities when adapting to similar environments.

Divergent Evolution

species sharing a common ancestor become more different over time.

Analogous Structures

Body parts that share a common function, but not structure.

Biogeography

Study of past and present distribution of organisms.

Continental Drift

continents moving over time

Microevolution

Change in allele frequencies in a population over generations.

Mutations

The source of all genetic diversity.

Crossing over

homologous chromosomes exchange portions of their chromatids

Independent assortment

Independent segregation of genes

Fertilization

male and female reproductive cells join to form a new cell.

Population genetics

Study of allele frequency distribution and change under the influence of evolutionary processes.

Gene pool

Combined genetic information of all the members of a particular population.

Hardy-Weinberg equilibrium

frequency of alleles in gene pool remain constant over time.

Hardy-Weinberg equation

p^2 + 2pq + q^2 = 1

Genetic drift

allele frequency change quickly due to event, Bottleneck Effect and Founder’s Effect

Founder effect

Change in allele frequencies, migration to create new population

Bottleneck effect

A change in allele frequency following population plummeting

Gene flow

Movement of alleles in or out of a population due to the migration of individuals

Relative fitness

The contribution an individual makes to the gene pool of the next generation

Directional selection

Occurs when natural selection favors a variation of a trait.

Disruptive selection

Favors individuals at both extremes of the phenotypic range.

Stabilizing selection

Natural selection that favors intermediate variants by acting against extreme phenotypes.

Diploidy

the presence of two complete sets of chromosomes in an organism's cells.

Heterozygous advantage

Heterozygous alleles have greater selective advantage.

Speciation

The formation of a new species

Macroevolution

speciation

Biological species concept

Species is a group of populations whose members have the potential to produce fertile offspring.

Reproductive isolation

Separation of species or populations so that they cannot interbreed and produce fertile offspring.

Prezygotic barriers

stops individuals from mating

Postzygotic barriers

Prevents hybrid zygote from developing into a viable, fertile adult.

Habitat isolation

Two species occupy different habitats, not isolated by physical barriers.

Behavioral isolation

different mating behavior

Temporal isolation

reproduce at different times.

Mechanical isolation

Morphological differences can prevent successful mating.

Gametic isolation

sperm can’t fertilize egg

Reduced hybrid viability

genes of different species interact and impair hybrid development.

Reduced hybrid fertility

Sterile hybrids due to uneven chromosome number.

Hybrid breakdown

Hybrid is fertile, but when they breed the next generation is sterile.

Allopatric speciation

The formation of new species in populations that are geographically isolated from one another.

Sympatric speciation

The formation of new species in populations that live in the same geographic area.

Autopolyploid

An individual that has more than two chromosome sets that are all derived from a single species.

Adaptive radiation

An evolutionary pattern in which many species evolve from a single ancestral species.

Gradualism

evolution occurs slowly but steadily.

Punctuated equilibrium

long stable periods are interrupted by brief periods of more rapid change.

Protocells

An abiotic precursor of a living cell that had a membrane-like structure and that maintained an internal chemistry different from that of its surroundings.

Oparin and Haldane

Proposed that the primitive atmosphere contained methane, ammonia, hydrogen, and water. these gases collided, producing chemical reactions that eventually led to organic molecules.

Miller and Urey

Tested the hypothesis that life began from simple organic molecules (proteins-amino acids) by creating the conditions of early earth within the lab.

Self-replicating RNA

first genetic material.

Ribozymes

RNA molecules that function as enzymes.

Fossil record

Chronological collection of life's remains in sedimentary rock layers.

Paleontologists

Scientists who study fossils.

Relative dating

determining the age of a fossil by comparing its placement with that of fossils in other layers of rock.

Radiometric dating

The process of measuring the absolute age of geologic material by measuring the concentrations of radioactive isotopes and their decay products.

Prokaryotes

Single-celled organisms without a nucleus.

Endosymbiosis evidence

Mitochondria & chloroplasts have their own DNA, double membranes, and reproduce through binary fission.

Multicellular eukaryotes

Plants, animals, fungi

Colonization of land

Occurred about 500 million years ago when plants, fungi, and animals began to appear on Earth

Panagea

landmass

Mass extinctions

The extinction of a large number of species within a relatively short period of time.

Mesozoic Era

middle life; rise of mammals and dinosaurs; the rise of birds; extinction of dinosaurs, rise of flowering plants.

Cretaceous extinction

The extinction of more than half of all species on the planet, including the dinosaurs.

Permian Extinction

Largest mass extinction in history, as it wiped out about 90% of all marine animal species.

Cambrian Explosion

lots of species emerged at once

Homeotic genes

control spatial organization of organism

Phylogeny

Evolutionary history of a species or group of species.

Phylogenetic trees

Branching diagrams that depict hypotheses about evolutionary relationships.

Molecular systematics

uses nucleic acids or other molecules in different species to infer evolutionary relationships.

Cladogram

Diagram that shows the evolutionary relationships among a group of organisms

Clade

A group of species that includes an ancestral species and all its descendants.

Shared derived characters

An evolutionary novelty that is unique to a particular clade.

Molecular clocks

Evolutionary timing methods based on the observation that at least some regions of genomes evolve at constant rates.

3 domains of life

Bacteria, Archaea, Eukarya