Modes of Speciation

Question 1

List the 4 modes of speciation

Answer 1

allopatric, sympatric, parapatric, peripatric

Question 2

What causes allopatric speciation?

Answer 2

A geographical barriers between species

Question 3

What causes sympatric speciation?

Answer 3

genetic polymorphism (evolution of a new species from a surviving ancestor, inhabiting the same area)

Question 4

What causes parapatric speciation?

Answer 4

partial spatial isolation (across large area where geographical variances occur and specific mutations may increase survival)

Question 5

What causes peripatric speciation?

Answer 5

isolation of a population of the periphery, a new species evolves from an isolated peripheral species

Question 6

Define species

Answer 6

group of similar individuals that are capable of sharing genes and breeding/inbreeding

Question 7

Define speciation

Answer 7

one species splits into two or more separate species. Requires an isolating mechanisms to limit or prevent gene flow

Question 8

Define biodiversity

Answer 8

number & range of different species that exist

Question 9

Recall the process of speciation

Answer 9

1. Variation
   Must have different genotypes
2. Isolation
   Different groups of population prevented from interbreeding
   Prevents gene flow -> stops differences from one population reaching another
   Via oceans, rivers, mountains, temperature etc.
3. Selection
   Natural selection occurs

Question 10

Define isolating mechanisms

Answer 10

intrinsic characteristics of species that reduce or prevent successful reproduction with members of other species.

Question 11

What are 4 examples of isolating mechanisms?

Answer 11

geographical, temporal, behavioural, reproductive

Question 12

When can these mechanisms occur?

Answer 12

Prezygotic and postzygotic