bio 3030 final

Uniformitarianism

the rates of change that we see today have been the same through earth history . processes of change are uniform

Catastrophism

the world came about very quick through sudden chromatin changes - great flood, in 7 days
-exclusive idea until 1800s

Lamarckism

(disproven theory) inheritance of acquired traits= changes to an organism during a lifetime are passed on its offspring

Natural selection

process that promotes the maintenance and spread of traits that enhance survival and fecundit

individuals vary
heritable component to variation
individuals with certain attributes survive and/or reproduce better than others

evolution by natural selection consist of?

Adaptation

-attunement to the environment
-a trait that increases fitness in a particular environment
-only get from natural selection

purifying selection

selection for the current phenotype (keeping the phenotype exactly the same)

disruptive selection

selection for two different allele states

directional selection

-selection away from the current phenotype
-replacement of one allele with another

hardy weinburg model is?

to calculate allele frequencies in the next generation
-what happens to alleles in the next generation

key assumptions of hardy weinburg equilibrium

No natural selection on allele
No genetic drift
Random mating
Also no migration of allele for another population

genetic drift

-evolution due to chance events in small populations
-change in allele frequency due to sampling error

neutral theory

most evolutionary change in dna sequences (sequence evolution) is due to genetic drift of mutant alleles that are selectively neutral (Motoo Kimura)

synonymous mutation

when a change in nucleotide sequences doesn't change amino acid sequence

non-synonymous mutation

when a change in nucleotide does change the amino acid sequence

primordial soul model

life began from a series of chemical reactions in water on earth's surface triggered by an external energy source such as lightning strike or ultraviolet (UV) light
Hypothesis

primordial soup model hypothesis

Spontaneous appearance of organic molecules
Emergent properties- resulting in more complex macromolecules
An evolutionary selection occurred for self replication and membrane compartmentalization

RNA world hypothesis

life on earth began with a simple RNA molecule that could copy itself

-RNA can serve as both a genetic code and a folded structure that enables enzymatic function

why did RNA world start

chimera hypothesis

In biology, a chimera is an organism containing a mixture of genetic material from 2 or more (usually distant related) species
-an achaean and bacteria fused to form one

endosymbiont hypothesis

-mitochondria lived inside primitive eukaryotes and evolved to become co dependent
-may have started as a parasite or undigested food

complex life evolved without mitochondria

endosymbiont hypothesis

complexity was not possible without mitochondria

chimera hypothesis

why was the evolution of eukaryotic/mitochondria significant?

Eukaryotes escaped the need for extreme efficiency and replication speed

the organization of the eukaryotic cell

Mitochondrion lost 99% of its genome
Nucleus gained tens of thousands of genes

modern eukaryotic cell

mitochondrial component- metabolic and biosynthesis functions

what are the archaeon & bacterial genomes in eukaryotes?

nuclear DNA(archaeon)
Mitochondrial DNA- (bacterial )

introns

the result of insertion of mitochondrial DNA into nuclear DNA

two adaptations in response to intron problem

spliceosome & nuclear membrane

spliceosome

molecular system that cuts out introns before translation
(already existed in bacteria

nuclear membrane

needed to physically separate transcription and translation

mitonuclear coadaptation hypothesis

selection for mitonuclear coadaptation is only possible if there is no heteroplasmy

mitonuclear coadaptation

The coordination of function by the products if the mitochondrial genome and the nuclear genome to achieve oxidative phosphorylation
,maintained by coevolution

genomic conflict hypothesis

avoiding heteroplasmy is necessary to avoid genomic conflict among mitochondria (selecting for faster replication speed)

genomic conflict

A conflict of interest within an organism wherein one or a set of genes have phenotypic effects that promote their own transmission to the detriment of the transmission of their genes that reside in the same genome

gene level selection hypothesis

Each gene promotes its own spread in the population
Natural selection acts at the level of the gene

selfish gene

does not harm other genes

outlaw genes

directly harm other genes

genomic conflict

contest among genes

the paradox of sex (two fold cost of sex)

lose 50% of reproductive advantage through asexual reproduction
-when producing sexually. female is only 1/2 related to offspring

red queen hypothesis (adaptable genotype theory of sex)

Asexual does not produce enough and is not diverse enough to keep up with environmnetal changes
Pathogen co evolution is proposed as the main driver of sex

sexual reproduction

the production of descendent individuals by combining t=genetic information from “parent” individuals

asexual reproduction

genome is copied and transmitted to descendants

advantages & disadvantages of asexual reproduction

-would gain 50% greater reproductive advantage
-

advantages & disadvantages of sexual reproduction

-reproducing sexually, a female is only 1/2 related to offspring
-cost of mate searching, sexual diseases, destruction of successful gene combinations
-recombination (advantage)

antagonistic pleiotropy

when the fitness effect of a gene is both positive and negative

antagonistic pleiotropy of aging

natural selection favors genes that bestow benefits early in life even if they carry a cost late in life

How is the germline shielded from mutation?

The mitochondria of female germ cells are almost never metabolically active.

r selected species

invest more ein reproduction and less in self maintenance for survival (rat and finch)
-short life, more reproduction

k selected species

invest less in reproduction and more in self maintenance for survival
-long life, less reproduction

2 broad methods for constructing phylogenies

phenetics & cladistics

phenetics

method for constructing phylogenies based on the overall similarity of the organisms . total shared traits
Group organisms by similarity

cladistics

method for constructing phylogenies based on shared derived characters

homology

similar by descent (inherit trait from common ancestor)

homoplasy

similar due to convergent evolution (independently evolve trait)

cladogenesis

formation of 2 or more species from an ancestral species (speciation)

anagenesis

evolutionary change within a species (lineage) over time. descent with modification (adaptation)

biological species concept

-s species sia by interbreeding population reproductively isolated from all other populations

“Good species do not hybridize”

phylogenetics species concept

-a species is any group of organisms with a unique evolutionary history as diagnosed by one or more traits
-any diagnosable (difference) group is a species

proximate causation

the developmental and physiological mechanisms responsible for the trait

ultimate causation

the evolutionary forces that shape the trait

hamiltons rule

social behavior evolves under specific combinations of relatedness, benefit and cost
B x R > C

eusociality

behavior pattern where some individuals do no reproduce to promote the reproduction of others

intrasexual selection

male-male competition
-direct contents for access to mates
-leads to the evolution of armaments

intersexual selection

female mate choice
-coercing females into choice
-leads to evolution of ornaments

indicator trait hypothesis

ornamental traits are honest signals of male quality
-by choosing ornamental traits, female gain fitness benefits beyond attractive sons

genotype
physical condition/resources

what determines male quality

mutualism

two species benefits from the activity of each other

symbiosis

two species depend on the existence of each other

coevolution

changes in the allele frequency in the genome of one species affects the allele frequencies in the genome of a second species

life on earth started

3.5 billion years ago

the big bang was

14 billion years ago

eukaryotes came about

2 billion years ago

earth was created

4.5 billion years ago

gene,group,individual are

the individual

with two mating types

you lose half of the mates