Classification

Classification

Classification

The grouping of organisms by similarities

Taxonomy

A system of naming and classifying organisms based on shared characteristics and universal rules

Cladogram

Diagram depicting patterns of shared characteristics among species

Binomial Nomenclature

The classification system in which each species is assigned a two-part scientific name. The first part is the genus name, and the second part is the species name EX: Homo Sapiens

Phylogeny

The study of the evolutionary history of lineages of organisms

Derived character

A trait that arose in the most recent common ancestry of a lineage and was passed to its descendants.

Evolution

A process of change over time.

Natural Selection

A theory by which organisms that are most suited to their environment survive and reproduce most successfully; also called survival of the fittest. This theory supports the process of evolution.

Adaptation

Heritable characteristics that increase an organism’s ability to survive and reproduce in an environment.

Species

a group of organisms that breed with one another and produce fertile offspring (all individuals come from the same gene pool).

Speciation

the process that leads to the formation of new species.

Charles Darwin

Traveled the Galapagos Island to look for the finches, made a theory called natural selection

Artificial selections

Where humans select and breed animals for specific traits

Variation

Members of any given species are never exactly alike.

Inheritance

The differences from Variation must be heritable.

Selection (survival & reproduction)

Resources are limited causing less organisms to live than are born (overproduction) Thoses who survive pass on there DNA.

Time

As a result to adaptations the population becomes better environment. “Populations evolve, NOT people

Biological Fitness

Tied to reproductive success, the better organism is at passing on thier genes, the more fit they are

Ideas before natural selection

Jean Baptiste Lamarck had the idea of inheritance of Acquired traits

Mimicry

Copying another organism in order to survive.

Trickery

Using color patterns to confuse predators

Camouflage

Being able to blend into surroundings.

Evidence Fossils

Any evidence of an organism that lived long ago.

Relative dating

Putting fossils in chronological order of age because there is no actual numerical data.

Absolute dating

Assign an actual age to fossils based on the half-life decay of chemicals Ex: Radiometric

Homologous structures

Similar physical structure, but with different uses EX whale flippers or human hand

Analogous structures

similar function, but different in physical structure EX butterfly or bat wings

Vestigial organs

Organs that remain but no longer have function

Embryology

study of how organisms develop

Causes of genetic variation

Mutations. Also Random mutations that are heritable are passed on from parents to offspring

Gene shuffling

bringing together a new combination of genes EX crossing over

Gene flow

Movement of individuals & alleles in & out of populations (causes genetic mixing)

Directional selection

when individuals with one extreme form of a trait outcompete the moderate and other extreme form of trait

Stabilizing selections

When individuals with the middle/ moderate form of a trait outcompete the two extremes.

Disruptive selection

when an individuals of both extreme forms of a trait outcompete the middle/ moderate form

Genetic drift

is a mechanism of evolution in which allele frequencies of a population change over generations due to chance.

Founder effect

a situation is which the traits available change as a result of the migration if a small subgroup of a population.

Reproductive isolation

keeping populations separated so they are unable to breed eventually creating separate gene pools

Temporal isolation

When two populations reproduce at different times and thus unlikely to meet up when seeking mates

Geographic isolation

When two populations are separated by geographic barriers (EX rivers or mountains) so unlikely to encounter one another

Behavioral isolation

When to populations have different courtship rituals or other types of behaviors and thus find each other unattractive.

Mass extinction

sudden death of organisms within an ecosystem, which opens up a lot of niches for other organisms to move into

Adaptive Radiation

when a single species evolves into several different species over time.

Convergent evolution

when unrelated organisms resemble one another because of the environment that they live in

Coevolution

when two species evolve in response to changes in each other over time so they evolve together.

Gradualism

organisms are always changing at a slow and constant pace

Punctuated equilibrium

long periods of stabilization followed by short periods of rapid evolution.