BIO120 TEST #2 UOFT LECTURE 9-15

taxonomic diversification

divergence causing a change in species name

Taxonomy

The scientific study of how living things are classified; like the vocabulary to the grammar of systematics

Carol Linnaeus

"Father of Taxonomy"; established his classification of living things; famous for animal naming system of binomial nomenclature; came BEFORE Darwin

sympatric

within a region

Allopatric

across regions

taxonomic (morphological) naming of species

naming based mostly on distinct measurable differences

biological naming of species

naming based on inter-fertility

Biological Species Concept (BSC)

Defines species as groups of interbreeding populations that are reproductively isolated from other groups

allopatric speciation

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

vitelline envelope receptor (VERL)/Lysin interaction

an example of reproductive isolating barrier (prezygotic barrier) in Lecture 9, VERL (egg of abalone) only takes specific lysin sperm. Like a molecular "lock and key"

pre-zygotic barriers

A reproductive barrier that impedes mating between species or hinders fertilization if interspecific mating is attempted, so NO zygote gets formed (geography, ecology, temporal, behaviour, mechanical [genital compatibility], cellular)

apple maggot flies

have different timing of mating depending on preferred host plant; example of prezygotic barrier because the different mating periods reduces fly gene flow by 94%!!! in sympatry

post zygotic barriers

prevent proper functioning of zygotes once they are formed; caused by combinations of genes with low fitness in the hybrid; CANNOT be favored by natural selection;

Intrinsic Postzygotic Barriers

hybrid inviability, hybrid sterility, or abnormal development of hybrids

Extrinsic Postzygotic Barriers

mismatch of phenotypes in hybrids to environment

sterile

incapable of reproducing

Hinny

cross of a male horse and female donkey; opposed to mules which is vice versa. example of intrinsic postzygotic isolation in lecture 9

Heliconius butterflies

example of extrinsic post-zygotic isolation; CAN form hybrids, but those hybrids can't mate and are less viable

ecological speciation

the evolution of reproductive barriers between populations by local adaptation

correlation

4 things commonly ID an adaptive radiation:
1) recent common ancestry
2) phenotype-environment ______________
3) trait utility
4) rapid speciation

clade

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

hybridization

the exchange of genes between species

key innovation

what causes adaptive radiations?
1) ecological opportunity
2) __________________________
3) high rates of speciation to characterize the clade

ploidy

is the number of complete sets of chromosomes in a cell

polyploidy

A chromosomal alteration in which the organism possesses more than two complete chromosome sets. A form of sympatric speciation

allopolyploidy

polyploidy resulting from contribution of chromosomes from two or more species; most COMMON type of polyploidy

Autopolyploidy

arises from duplicated karyotype within a species; an individual that has more than two chromosome sets that are all derived from a single species

Karyotype

an individual's complete set of chromosomes

speciation continuum

continuous sequence of genetically-based changes that occur as two lineages diverge from one another on the pathway to reproductive isolation. SPECIATION IS NOT A UNIDIRECTIONAL PROCESS

reproductively isolated

polyploids are _________ _____________ from their diploid parents

hybrid vigor

A phenomenon in which the hybrid state is selected because it has greater survival and reproductive success; also known as heterosis

Larmack's theory

all organisms have an inherent tendency to become more complex; wrong! only some lineages have evolved greater complexity in terms of cells, tissues types, physiology, development, reproduction, social behaviors ect.

cooperation

greater complexity arises from greater ____________ amongst previously independent units; independent of each other to dependent of each other. Human interaction is am example.

division of labor

specialization of parts to specific functions. (think intestines do something different to lungs and neither do both jobs)

merging of prokaryotes

in lecture 11 to exemplify greater complexity via merging

individual selection

natural selection of individual characteristics; usually stronger than "group selection" this might not always be good for the SPECIES

unit of selection

biological entity within the hierarchy of biological organization that is subject to natural selection

peacocks

example in lecture to show how evolution isn't perfect, illustrating that the individual selection outweighs the group selection There is a cost to increasing sexual fitness because the risk of predation is increased

reciprocal altruism

an organism acts in a manner that temporarily reduces its fitness while increasing another organism's fitness, with the expectation that the other organism will act in a similar manner at a later time; repeated cooperation. think prison dilemma

high relatedness

a mode of adaptive cooperation; genes lead to helping relatives can spread via natural selection: think oldest child growing up to help parents raise own kids

breaking down

cooperation is capable of ______ because of "cheaters"; both side might not benefit

genes

the unit of inheritance. THE TARGET OF SELECTION; _________ typically persist by improving the fitness of the GROUP

fair representation

mitosis and meiosis ensures this. genes vary so alleles can't compete within an individual

chimera of zygotes

example in lecture 11: to describe initial competition between cell lineages. when two cells in early development fuse and induces internal competition

meiotic drive

allele biases its own transmission spreading to higher frequency even while reducing fitness; CAN RAPIDLY ELIMINATE ALLELES THAT HAVE HIGHER INDIVIDUAL FITNESS

transposable elements

DNA sequences that have the ability to change their position within a genome. can make over 50% of DNA in genomes of some species, so selfish!!!!

single cell

starting from a _______ prevents initial competition between cell lineages

piRNA and RNA interference

have evolved as silencing mechanisms of transposable elements; or else genomes will EXPLODE!!!! an example of how individual selection favors alleles arising elsewhere that silence TEs, preventing CHEATING

DNA methylation

mutations in genes for _____________________ leads to rampant activation of TEs; this is NOT good. CHEATING!!!!

uniparental inheritance

inheritance pattern in which the progeny have the genotype and phenotype of one parent only, for example, chloroplasts and mitochondria replicate asexually; this PREVENTS COMPETITION within cells of different organelle genomes

transposition-selection balance

an equilibrium in the number of deleterious alleles in a population that occurs when the rate at which deleterious alleles are created by mutation equals the rate at which deleterious alleles are eliminated by selection

mitochondrial transmission

lack of mitosis and meiosis of organelles sets up potential for spread of selfish elements; MAINTAINS COOPERATION (eg active exclusion of sperm mitochondria at fertilization)

maternal

Uniparental inheritance has CONFLICT OF INTEREST!!! mitochondrial mutations that enhance __________ fitness can spread even if cost is severe to male fitness

Cytoplasmic Male Sterility (CMS)

mutations in mitochondria can make hermaphroditic plants "male sterile" so plants are entirely female. Plant loses the ability to produce functional male reproductive organs or pollens, resulting in flowers that only function as female. This means that flowers will rely on pollen from other plants to reproduce, enhancing genetic diversity in agricultural breeding

arms race

CMS has led to the evolution of nuclear "restorer" alleles that reenable fertility through pollen -> ______________ co-oevolution of CMS and restorer genes

germline

separation of _________ with limited numbers of cell division inhibits transmission of selfish cell lineages; helps cooperation along with tumor suppressors, starting with a single cell to reduce competition

cancer

example of selfish cell lineages evolving within an individual; illustrates the shortsightedness of the evolutionary process since cancer EVEOLVES resistance to treatment

alleles

spread through a population by increasing individual fitness

Fair meiosis

provides equal representation of alleles' fitness effects on individuals

Reproductive isolation

Separation of species or populations so that they cannot interbreed and produce fertile offspring; sometimes this only results in infertile males

Taxon

a single named taxonomic unit at any level

systematics

how we actually study biodiversity and the evolutionary relationships amongst organisms that we happen to give a name

monophyletic group

a single ancestor gave rise to all species in that taxon and no species in any other taxon; preferred class

paraphyletic group

a taxon whose members are derived from two or more ancestral forms not common to all members

reptiles

example used in Lecture 9 of a name of a group that doesn't correctly match up with phylogenetic grouping, excluded birds even though they are closely related

ancestral trait

a trait shared w/ a common ancestor

derived trait

a trait that differs from the ancestral trait in a lineage; characteristics that have evolved since ancestral species

Homology

similar traits from common ancestry

homoplasy

similarity of traits as a result of convergent evolution

convergent evolution

independent accumulation of mutations and changes in a given species that cause unrelated species to resemble one another and function similarly

spurge

Cactus, milkweed, and _________ that have independently evolved to have similar structures to prevent water loss. Example in Lec 9 of convergent evolution

cichlid

fish that dominate the African great lakes; example in Lec 9 of convergent evolution. They converged in body forms independently in separate lakes as they radiated.

antibiotic resistance in bacteria

something we create strong selective pressure on, example in lecture 12 of a problem humans need to tackle and prevent

herbicide resistance

hundreds of weedy plants have evolved _________________ because of extensive use of chemicals; caused by 1) preexisting variation, 2) gene flow, or 3) mutations arising that allow it

Canada Fleabane

ex. Lec 12. A weed that spread through Southern Ontario that developed herbicide resistance

selfing weeds

outcrossing weeds have more preexisting resistance variation than _____________ ; reproductive mode affects the source of resistance!!!

multi-herbicide treatment

makes adaptation for resistance less likely b/c evolving for multiple compounds is more complex

evolutionary rescue

rapid evolution in populations in response to environmental change can allow the population to regain positive growth rates before extinction; this something we want to AVOID with weeds

insecticide resistance

more and more mosquitoes are evolving to have this as humans put selective pressure into eradicating them; this is a major problem for the spread of malaria!!

responsive alternation

using another insecticide once a resistance forms

combination

an evolution proof mode of controlling mosquitoes population; PROBLEM: might affect other species of insects we care about too

multi-drug cocktails

slows the evolution of HIV resistance b/c mutations are less likely to have resistance to many drugs at once

habitat fragmentation

Breakup of a habitat into smaller pieces, usually as a result of human activities.

ecology

The study of how organisms interact with each other and their environment. the distribution and abundance of species. Structure of environments. study of biodiversity. _________ is the setting where evolution takes place. The "WHY" to the HOW

Theodosius Dobzhansky

says "Nothing in biology makes sense except in the light of evolution"

endosymbiotic theory for the development of mitochondria

ex of the study of EEB Lec13. Lynn Margulis's explanation for the origin of the mitochondria. "Life did not take over the globe by combat, but by networking"

extrapolate

88% species are unknown, we have to ___________ from the number of taxa found daily. 8.7 million species givetake a million eukaryotic species exists

model organisms

mice to represent all vertebrates, fruit flies for all insects, plants for all plants.

lime disease

Caused by bacterium Borelia. ex Lec13 for how EEBs also want to understand the patterns of distribution of infectious diseases.

cougars

have a very large geographic range compared to something like the American Pika. Ex Lec 13. EEBs need to ask WHY the distribution is like that so we can know how to manage agriculture + to make predictions as to where species will live in response to climate.

dispersal

what determines where species live (factors that determine patterns of distribution)? _______________, abiotic conditions (soil, climate, nutrients etc), species interactions (species don't live in a vacuum, they need to manage competition and predation)

inexhaustible conditions

temperature, salinity, etc

exhaustible resources

food, space. Things that get used up as a factor that limits species distribution

environmental gradient

a graph that shows how the majority of the proportion of species: reproduction > growth > survival

racoons

example of species that are abundance; compared to Galapagos turtles, which is a species that is rare. EEBs want to know WHY

Malthus

helps to explain what determines abundance: population growth is dependent on the availability of resources -> there is then competition and natural selection to combat the limited resources

the sixth extinction

we are in the midst of ________________ because of human activity that contribute to global warming. 32% of know vertebrates are decreasing in population size or distribution

Spix's Macaw

Lec14 example of a species extinct in the wild; currently trying to be reintroduced into the wild

ecological niche

"a species's place in the world"

Hutchinsonian niche

an n-dimensional hypervolume in which each axis is an ecological factor important to be considered; outside the blue gradient the conditions are unsuitable