Honors Bio Evolution 2024-2025 - Carrico

Evolution

Change over time

Darwin's three patterns of biodiversity

1. Species vary globally

2. Species vary locally

3. Species vary over time

Fossils

The preserved remains or traces of organisms that once lived on Earth.

Hutton + Lyell's conclusions about Earth's history

1. The Earth is extremely old 2. The processes that changed Earth in the past are the same processes that operate in the present

Uniformitarianism

The laws of nature are constant over time

Lamarck's (incorrect) suggestions

1. Organisms can change over time by selectively using or not using various parts of their bodies 2. Individuals can pass these acquired traits onto their offspring

Malthusian Theory

The theory that population grows faster than food supply

Artificial selection

nature provides the variations and humans select those they find useful

Adaptation

A trait that helps an organism survive and reproduce

Fitness

Ability of an organism to survive and reproduce in its environment

Natural selection

A process in which individuals that have certain inherited traits tend to survive and reproduce at higher rates than other individuals because of those traits.

The principle of common descent

All species-living and extinct-are descended from ancient common ancestors.

Biogeography

Study of past and present distribution of organisms

Homologous structures

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

Analogous structures

Body parts that share a common function, but not structure

Vestigial structures

A structure that is present in an organism but no longer serves its original purpose

Evidence of common descent

Universal genetic code and homologous molecules

The Grants' documentations were...

Natural selection in wild finches takes place frequently and sometimes rapidly

The Grants' work shows...

Variation within a species increases the likelihood of the species' adapting to and surviving environmental change

Gene pool

The stock of different genes in an interbreeding population.

Allele frequency

Number of times that an allele occurs in a gene pool compared with the number of alleles in that pool for the same gene

Evolution involves...

a change in the frequency of alleles in a population over time

Sources of genetic variation

1. mutation 2. genetic recombination during sexual reproduction 3. lateral gene transfer

The number of phenotypes for a given trait...

Are dependent on how many genes control the trait

Single-gene trait

A trait that is controlled by only one gene

Polygenic trait

A trait controlled by two or more genes

Natural selection on single-gene traits

Changes allele frequencies, and ultimately, changes in phenotype frequencies

Natural selection on polygenic traits

Can affect the relative fitness of phenotypes and thereby produce one of three types of selection: directional selection, stabilizing selection, or disruptive selection

Directional selection

when individuals at one end of the curve have higher fitness than individuals in the middle or at the other end

Stabilizing selection

When individuals near the center of the curve have higher fitness than individuals at either end

Disruptive selection

When individuals at the outer ends of the curve have higher fitness than individuals near the middle of the curve

Genetic drift

A change in the allele frequency of a population as a result of chance events rather than natural selection. (aka just random change)

Bottleneck effect

A change in allele frequency following a dramatic reduction in the size of a population

Founder effect

A change in allele frequencies as a result of the migration of a small subgroup of a population

Genetic equilibrium

A situation where a population does not evolve, and allele frequencies in its gene pool do not change

Hardy-Weinberg principle

A principle that states that allele frequencies in a population will remain constant unless one or more factors cause the frequencies to change

Sexual selection

When individuals select mates based on heritable traits

Species

A population or group of populations whose members can interbreed and produce fertile offspring

Speciation

The formation of a new speces

Reproductive isolation

When two populations become isolated and evolve into separate species

Behavioral isolation

Form of reproductive isolation in which two populations have differences in courtship rituals or other types of behavior that prevent them from interbreeding

Geographic isolation

Case where two populations are physically separated by geographic barrier(s)

Temporal isolation

When two species breed at different times of day, season, or years.

Molecular clock

Mutation rates in DNA that are used to estimate the time that two species have been evolving independently

Hox gene

series of genes that controls the differentiation of cells and tissues in an embryo (can lead to big changes later in life)

Binomial nomenclature

Classification system in which each species is assigned a two-part scientific name

Genus

A group of similar species

Systematics (or taxa)

the science of naming and grouping organisms

Linnaean System

(KPCOFGS) Kingdom, Phylum, Class, Order, Family, Genus, Species

Family

Group of genera that share many characteristics

Order

Group of similar families

Class

Group of similar orders

Phylum

Group of closely related classes

Kingdom

the most general of the seven levels of classification (ex: all multicellular animals are placed in the kingdom Animalia)

Phylogeny

The evolutionary history of lineages

Clade (or monophyletic group)

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

Cladogram

Diagram that shows the evolutionary relationships among a group of organisms

Derived character

A trait that arose in the most recent common ancestor of a particular lineage and was passed along to its descendants

Domain

A larger, more inclusive category than a kingdom

Bacteria

Domain that is unicellular and prokaryotic

Archea

Domain of unicellular prokaryotes that have cell walls that do not contain peptidoglycan

Eukarya

domain consisting of all organisms that have a nucleus; includes protists, plants, fungi, and animals

Evolution

Change over time

Darwin's three patterns of biodiversity

1. Species vary globally

2. Species vary locally

3. Species vary over time

Fossils

The preserved remains or traces of organisms that once lived on Earth.

Hutton + Lyell's conclusions about Earth's history

1. The Earth is extremely old 2. The processes that changed Earth in the past are the same processes that operate in the present

Uniformitarianism

The laws of nature are constant over time

Lamarck's (incorrect) suggestions

1. Organisms can change over time by selectively using or not using various parts of their bodies 2. Individuals can pass these acquired traits onto their offspring

Malthusian Theory

The theory that population grows faster than food supply

Artificial selection

nature provides the variations and humans select those they find useful

Adaptation

A trait that helps an organism survive and reproduce

Fitness

Ability of an organism to survive and reproduce in its environment

Natural selection

A process in which individuals that have certain inherited traits tend to survive and reproduce at higher rates than other individuals because of those traits.

The principle of common descent

All species-living and extinct-are descended from ancient common ancestors.

Biogeography

Study of past and present distribution of organisms

Homologous structures

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

Analogous structures

Body parts that share a common function, but not structure

Vestigial structures

A structure that is present in an organism but no longer serves its original purpose

Evidence of common descent

Universal genetic code and homologous molecules

The Grants' documentations were...

Natural selection in wild finches takes place frequently and sometimes rapidly

The Grants' work shows...

Variation within a species increases the likelihood of the species' adapting to and surviving environmental change

Gene pool

The stock of different genes in an interbreeding population.

Allele frequency

Number of times that an allele occurs in a gene pool compared with the number of alleles in that pool for the same gene

Evolution involves...

a change in the frequency of alleles in a population over time

Sources of genetic variation

1. mutation 2. genetic recombination during sexual reproduction 3. lateral gene transfer

The number of phenotypes for a given trait...

Are dependent on how many genes control the trait

Single-gene trait

A trait that is controlled by only one gene

Polygenic trait

A trait controlled by two or more genes

Natural selection on single-gene traits

Changes allele frequencies, and ultimately, changes in phenotype frequencies

Natural selection on polygenic traits

Can affect the relative fitness of phenotypes and thereby produce one of three types of selection: directional selection, stabilizing selection, or disruptive selection

Directional selection

when individuals at one end of the curve have higher fitness than individuals in the middle or at the other end

Stabilizing selection

When individuals near the center of the curve have higher fitness than individuals at either end

Disruptive selection

When individuals at the outer ends of the curve have higher fitness than individuals near the middle of the curve

Genetic drift

A change in the allele frequency of a population as a result of chance events rather than natural selection. (aka just random change)

Bottleneck effect

A change in allele frequency following a dramatic reduction in the size of a population

Founder effect

A change in allele frequencies as a result of the migration of a small subgroup of a population