more stuffs for final midterm

Question 1

what is speciation

Answer 1

process by which lineages split into independent evolutionary trajectories

Question 2

if evolution consists of change in allele frequency, what is speciation

Answer 2

lack of gene flow

Question 3

what are the two forms of reproductive barriers

Answer 3

prezygotic and posyzygotic

Question 4

what is a prezygotic RI

Answer 4

dont meet, dont mate, or mate but it doesn’t fertilize

Question 5

what is postzygotic RI

Answer 5

reduced hybrid fitness

Question 6

what are the speciation concepts

Answer 6

morphospecies species concept
phylogenetic species concept
biological species concept

Question 7

what is the morphospecies species concept and pros and cons

Answer 7

species defined by unique morphological characteristics

pros: simple, applies to extinct and asexual too
cons: no clear genetic/evolutionary justification (could be arbitrary)

Question 8

what is the phylogenetic species concept and pros and cons

Answer 8

species= smallest (monophyletic) group thats defended from a common ancestor that possesses diagnosable traits (genetic or morphological)

pros: testable, quantifiable, even works for asexuals

Cons: phylogenies are just estimates. Also any trait unique to a population however trivial defines them as a distinct species

Question 9

what is biological species concept and pros and cons

Answer 9

species are groups of (potentially) interbreeding natural populations

pros: simple
cons: only applies to extant sexual species, also populations can live in different places and still be able to interbreed (Liger)

Question 10

what are the types of geography of speciation

Answer 10

allopatric, peripatric, parapatric, symoatric

Question 11

what is allopatric mean

Answer 11

geolographical barrier

Question 12

what does peripatric mean

Answer 12

peripheral population with founder effect

Question 13

what does parapatric mean

Answer 13

continuous population

coexist in same habitat but have distinct niches

Question 14

what does sympatric mean

Answer 14

no geographical separation

occupy same niche

Question 15

what is a cryptic species

Answer 15

2 or more species who were classified as a single species based on morphological similarities

Question 16

what is by-product selection

Answer 16

indirect natural selection leading to RI

Question 17

explain the two types of indirect natural selection

Answer 17

prezygotic: by-product selection

postzygotic selection: results from selection and adaptations to different niches

Question 18

what is direct natural selection also known as and explain it

Answer 18

reinforcement

which is when natural selection leading to prezygotic isolation as a result of reduced hybrid fitness

Question 19

what evolves faster prezygotic RI or postzygotic RI

Answer 19

prezygotic

Question 20

under what type of geographical speciation does prezygotoc isolation evolve faster

why

Answer 20

faster in sympatry than allopatry

since more possibility to make a mistake (making hybrid) there will be stronger selection to not (since populations mix under sympatry)

Question 21

what are the two types of sexual selection and explain them

Answer 21

environment specific: different sexual selection arises due to changes in environment

environment independent: sexual selection arises from interactions between sexes, independent of environment

Question 22

what s the Bateson - Dobzhansky - Muller model

Answer 22

1. population split in two
2. selection selects for different genotype in at least one of the populations
3. populations reconnect resulting in hybrids

shows evolution of genetic incompatibilities

Question 23

is speciation due to BDMs environment dependent or independent

Answer 23

can be either

Question 24

what is mutation oder speciation

Answer 24

when speciation is driven by BDMs incompatibilities driven by natural selection

Question 25

what is ecological speciation

Answer 25

speciation arising from reproductive isolation

Question 26

can BDM incompatibilities arise in the same environment

Answer 26

yes, tho it helps if they are different

Question 27

what is Haldane’s rule

Answer 27

in F1 hybrids, when only one sex is sterile/inviable it is usually the heterogametic sex (ex: XY)

Question 28

what is the general rule from quantitative trail loci theory

Answer 28

speciation is more likely if relevant traits are governed by fewer genes

Question 29

what is polyploidizaton

Answer 29

a form of mutation, change in number of whole sets of chromosomes

Question 30

what are the types of polyploidization

Answer 30

autopolyploidy

allopolyploidy

Question 31

what is autopolyploidy

Answer 31

more than two copies of homologous chromosomes that arises from fusion of gametes of the same species

Question 32

what is allopolyploidy

Answer 32

more than two copies of homologous chromosomes that arises from fusion of gametes of different species

Question 33

what does mitochondrial eve not mean

Answer 33

only one female alive then

we all have same mtDNA

Eve was anatomically modern

Question 34

what does mitochondrial eve mean

Answer 34

that non-africana populations older than 200 000 ya did not contribute mtDNA to modern humans

Question 35

what is an ancestral polymorphism

Answer 35

alleles can diverge before species does

Question 36

what are the hypotheses for evolution of typical primate traits

Answer 36

arboreal hypothesis: traits adapted to suit arboreal life

visual predation theory: traits evolved as adaptations for nocturnal insectivores

angiosperm radiation theory: early primates coevolved with flowering plants

Question 37

what are the features of modern synthesis

Answer 37

1. variation arises by mutations, most of which with small effect, and from recombination
2. change in populations due to natural selection
3. species are composed of variable populations
4. species arise through evolution of gradual RI
5. macroevolution is a result of 1-4

Question 38

what did mike Lynch theorize

Answer 38

larger species have smaller Ne so drift is stronger. so introns and mobile genetic elements stay in genome since drift is stronger than weak selection coefficient to get rid of them