Lecture 21: Speciation and Hybridization

Question 1

What is a species

Answer 1

phenotypic similarity based on how similar the species look

Question 2

Sympatric

Answer 2

species in the same geographic space

Question 3

Allopatric

Answer 3

species belonging to different geographical locations

Question 4

what is another widely used definition of a species

Answer 4

phylogenetic species concept, looking at genetic similarities

Question 5

Taxonomic (morphological)

Answer 5

this is based on the measurable differences of varying individuals

Question 6

Biological Species concept

Answer 6

based on if 2 individuals can reproduce with one another.

Question 7

What species concept did Darwin look at

Answer 7

taxonomic which he explained to be incidental microevolutionary

Question 8

Explain some of the points of BSC

Answer 8

focuses on the process
tests that if the geological Barries go away will the 2 be capable of reproducing

Question 9

if two individuals reproduce successfully in a lab does it mean they belong to the same group?

Answer 9

No because this doesn’t guarantee that they will do so in the wild

Question 10

Where does speciation occur

Answer 10

allopatric speciation is more common because evolution with minimal gene flow, so they end up evolving separately due to geographical distance

Question 11

What causes reproductive isolation

Answer 11

anything that goes wrong during post-zygotic phase

Question 12

What are pre-zygotic barriers

Answer 12

geography
behaviour
genetic structure
sperm-egg compatibility

Question 13

What are post-zygotic barriers

Answer 13

intrinsic (sterility)
extrinsic (populations that cannot survive the environment

Question 14

How and why do organisms diverge?

Answer 14

mutations
natural selection
genetic drift

Question 15

Why do we have so many species on earth

Answer 15

due to speciation

Question 16

Adaptive radiation

Answer 16

evolution of phenotypic diversity in a species

Question 17

what identifies an adaptive radiation

Answer 17

1. common ancestor
2. rapid speciation
3. phenotype-environment correlation
4. Trait utility

Question 18

Hybridization

Answer 18

Exchange of genes between species due to inter species mating

Question 19

polyploids

Answer 19

individuals with additional copies of genome

Question 20

allopolyploidy

Answer 20

arises from hybridization where duplicated karyotypes between species

Question 21

evolutionary significance of polyploid

Answer 21

high fitness
reproductively isolated from parents making them sympatric speciation