T9

Question 1

SPECIES

Answer 1

a group of organisms that can reproduce to produce fertile offspring

Question 2

courtship behaviour

Answer 2

this looks at the behaviours of individuals when looking for a partner to see if the same species
can compare courtship behaviours to determine this

Question 3

anagensis speciations

Answer 3

selection acting within a species to cause it change, no ancestor maintained
linear change in species

Question 4

cladogensis

Answer 4

speciation is ancestral
the ancestral species evolves into 2 reproductively isolated decedent species

Question 5

pre zygotic -reproductive isolation

Answer 5

this is reproductive isolation that occurs before fertilisation/sex has taken place

can be due to
- different habitats
- different mating displays

preventing them from mating

Question 6

post zygotic

Answer 6

reproductive isolation after fertilisation

hybrid sterility - infertile offspring as two different species mating - mule

hybrid inviability - not developing into an offspring

Question 7

reproductive isolation importance

Answer 7

to prevent gene flow between populations to allow for divergence
- the allele frequencies can change between populations and allow them to evolve independently

Question 8

biological species concept

Answer 8

defines a species taxon as a group of organisms that can successfully interbreed and produce fertile offspringi

Question 9

issues with bio species concept

Answer 9

only applies to sexual organisms

requires substantial work to demonstrate

doesnt always work

Question 10

physiological, morphological, ecological species concepts

Answer 10

grouping organisms with these requirements as same species

can also apply to bacteria where no sexual reproduction

Question 11

phylogenetic species concept

Answer 11

quick and efficient

extract genetic information from individuals to generate a phylogenetic tree

form clusters of same species

Question 12

allopatric model of speciation

Answer 12

speciation through geographical isolation
1) initially populations in same environment
2) some event happens causing the environment/lake to split into 2 populations
3) now geographically isolated so no gene flow, different selection pressures, different allele selections, so populations can diverge and different traits
4) lake rejoins but still reproductively isolated as produce 2 different species, unable to reproduce

Question 13

sympatric isolation

Answer 13

speciation without geographic isolation
- requires divergence to occur in a population - which is much harder due to gene flow

examples
- polyploidy
- mechanical issues
- courtship behavhiours
- different fertility windows