Speciation

Question 1

What is allopolyploidy?

Answer 1

2 closely related species hybridize and form polyploid offspring

Question 2

What is autopolyploidy?

Answer 2

diploid individual may produce tetraploid offspring each of which has 4 complete sets of chromosomes

Question 3

What is clinical variation?

Answer 3

environment changes from different elevations (Ex. mountains)

Question 4

What is a ring species?

Answer 4

“could mate” Ex. Big and small dogs mating, very artificial

Question 5

What are unreduced gametes?

Answer 5

gametes spontaneously get the same number of chromosomes as a somatic cell

Question 6

What are the 3 specific types of speciation?

Answer 6

1. Allopatric speciation
2. Parapatric speciation
3. Sympatric speciation

Question 7

What is allopatric speciation?

Answer 7

when 2 populations are geographically separated

Question 8

What are the 3 types of allopatric speciation?

Answer 8

1. Species Cluster
2. Hybrid Zones
3. Reinforcement

Question 9

What is a species cluster?

Answer 9

a group of close related species recently descended from a common ancestor

Question 10

What are hybrid zones?

Answer 10

where members of each population may mate with individuals from the other before pre zygotic reproductive isolation is complete

Question 11

What is reinforcement?

Answer 11

natural selection promotes the evolution of pre zygotic isolating mechanisms which favours individuals who mate only with members of their own population when post zygotic isolating mechanisms cause hybrid offspring to have lower fitness

Question 12

What is genetic divergence in allopatric populations?

Answer 12

many traits that function as pre zygotic isolating mechanisms may have originally evolved in response to sexual selection

Question 13

What is parametric speciation?

Answer 13

speciation arising between adjacent populations, populations also adapt to different environmental conditions

Question 14

What is sympatric speciation?

Answer 14

reproductive isolation evolves between distinct subgroups that arise within a population

Question 15

What is a host race?

Answer 15

isolation from populations in the same species as a consequence of their adaptation to feed on a specific host plant species

Question 16

What are the 3 post zygotic isolating mechanisms?

Answer 16

1. hybrid inviability
2. hybrid sterility
3. hybrid breakdown

Question 17

What is hybrid inviability?

Answer 17

when the result of hybrid organisms die as embryos or at an early age because the 2 sets of developmental instructions do not interact properly

Question 18

What is hybrid sterility?

Answer 18

hybrids between closely related species produce adult offspring but they are not fertile and cannot reproduce

Question 19

What is hybrid breakdown?

Answer 19

when first generation hybrids are healthy and fertile but second generations exhibit reduced survival or fertility

Question 20

What are the 5 methods of pre zygotic speciation?

Answer 20

1. Ecological isolation
2. Temporal isolation
3. Behavioural isolation
4. Mechanical isolation
5. Gametic isolation

Question 21

What is ecological isolation?

Answer 21

species living in the same geographical region but do not interbreed

Question 22

What is temporal isolation?

Answer 22

species that live in the same habitat but mate at different times of the day or year

Question 23

What is behavioural isolation?

Answer 23

when the signals used for one species are not recognized by another species

Question 24

What is mechanical isolation?

Answer 24

differences in the structure of reproductive organs or other body parts that prevent individuals from breeding

Question 25

What is gametic isolation?

Answer 25

individuals of a different species mate but an incompatibility between the sperm and the egg prevents fertilization

Question 26

What is the morphological species concept?

Answer 26

when species are separated based on their morphological (phenotypic) characters and traits

Question 27

What is the biological species concept?

Answer 27

differentiates based on species that can interbreed and produce viable and fertile offspring

Question 28

What is the phylogenetic species concept?

Answer 28

defines species as a group of organisms bound by a unique ancestry

Question 29

What is the ecological species concept?

Answer 29

defines species as a group of unique organisms that share a distance ecological niche