eco test 1

Aristotle

Scala natura hierarchy (ancient greece 384-322bce)

robert hooke

microscope, bacteria & protists (enlightenment)

anton lee

bacteria and protists (enlightenment)

Jean Baptiste Lamarck

transformism (1774-1829)

george cuvier

paleontology, comparative anatomy

thomas malthus

economist, human population growth

alfred wallace

conducted field studies in south east asia, developed ideas on evolution very similar to Darwin

epigenetics

study of dna modifications that alter expressions

uniformitarianism

Hutton-the idea that geological processes have been occurring at roughly the same rates throughout time

james hutton

founder of modern geology

eugenics

The science of improving a human population by controlled breeding to increase the occurrence of desirable heritable characteristics.

adaptive radiation

The diversification of organisms that occurs when many niches are vacant

theory of evolution

All living things that exist today are descended from a common ancestor and adapt to their environments over time through the process of natural selection

theory of evolution explains…

homology, vestigial structures

homology

taxa inherit the same trait from a common ancestor

analogy

taxa independently evolve the same trait

microevolution

a change in allele frequency within a population over generations

macroevolution

describes evolutionary changes and patterns at or above the species level, especially things such as speciation and extinction

biological species concept

Species are determined by whether or not they can mate and produce fertile, viable offspring

horizontal gene transfer

involves the transmission of DNA between different organisms pr species as opposed to between parent and offspring

transduction

the horizontal transfer of DNA via viral vectors

conjugation

The transfer of genetic material between bacterial cells by direct cell-to-cell contact or by a bridge-like connection

transformation

Picks up DNA from the environment. No virus is involved

gene flow

The movement of alleles between populations. occurs via immigration or emigration and dispersal of gametes or seeds

genetic drift

chance reduction in population size, which results in changes in allele frequencies within a population

bottleneck effect

A reduction in population size caused by the survival of a random subset of the population following an environmental event

the founder effect

a small population that occurs as a result of the migration of a subset of a few individuals into a new geographic location

disruptive selection

When possessing either of the extremes of a trait is more adaptive than possessing the average trait

natural selection

can cause some phenotypes to be favored over others, causing changes in survivorship or fecundity

stabilizing selection

When extreme variants are less fit than intermediate types

directional selection

when variants at one end of an extreme are favored over variants on the other end of the extreme

sexual selection

can cause some phenotypes to be favored as mates over other phenotypes

Hamilton rule

A gene for altruism will spread only if the loss of direct fitness or the altruist is offset by the indirect fitness gains

eusociality

social strategy characterized by cooperative brood care

systematics

the branch of biology that focuses on
the identification and classification of species, and
their phylogenetic (evolutionary) relationships.

Taxonomy

a sub-branch of systematics that
focuses on classifying species and curating
taxonomic nomenclature

Cladistics

a sub-branch of
systematics that focuses on resolving evolutionary
relationships

carl linnaeus

Created our modern system of
taxonomy, including binomial
nomenclature

rules of taxonomic nomenclature

scientific name, genus name, species name, ranks above species

Sister groups

taxonomic pairs that share a common
ancestor

Polytomy

an un-resolved branch-point in a tree that
indicates we are unsure about which of 3 or more taxa
diverged first

Plesiomorphy

The original, ancestral
state of the characteristic

Apomorphy

The changed, or derived
character state

Synapomorphies

apomorphies shared by multiple taxa due to
common ancestry

Homoplasies

apomorphies shared by multiple taxa due to
convergent evolution

monophyletic group

a taxon that includes the ancestor and all of its
descendants

Paraphyletic taxon

a taxon that includes the ancestor and some but not
all of its descendants

Allopatric speciation

•occurs when reproductive isolation occurs due to geographic isolation.  When the barrier is removed, individuals can no longer interbreed.

Sympatric speciation

•occurs when reproductive occurs while populations are geographically overlapping

Prezygotic barriers

block fertilization from occurring

Postzygotic barriers

prevent the hybrid zygote from developing into a viable, fertile adult

Habitat isolation

Two populations  occupy different habitats, and so encounter each other rarely or never.

Temporal isolation

Populations that breed at different times of the day, different seasons, or different years cannot mix their gametes

Behavioral isolation

Courtship rituals and other behaviors unique to a population are effective barriers

Mechanical isolation

Morphological differences can prevent successful mating

Autopolyploidy

occurs when an organism exhibits multiple (>2) copies of its genome

Gametic isolation

Sperm of one species may not be able to fertilize eggs of another species

Reduced hybrid fertility

Even if hybrids are vigorous, they may be sterile

Hybrid breakdown

When first-generation hybrids are viable and fertile, but their F2 offspring are sterile or inviable

Proximate causation

The physical or molecular mechanisms underlying traits and behaviors (the
“how”; “zooming in”)

Ultimate causation

The ecological or evolutionary context that explains traits and
behaviors (the “why”; “zooming out”)

Abiotic Environment (non-living)

Physical factors: temperature, light, relative humidity,
precipitation etc.
– Chemical factors: pH, oxygen, nitrogen, phosphorus

Biotic Environment (living)

Other organisms (conspecifics and heterospecifics)