Diversity and Evolution

Question 1

natural selection

Answer 1

• heritable variation for a particular trait (morphology, behaviour) exists in a population
• individuals with the trait that is suited for the particular environmental conditions will be more likely to survive and reproduce, and thus the frequency of that trait will increase

(differential reproduction of inherited traits)

Question 2

adaptation

Answer 2

match of form and function to the environment

ex. no giant horns in dense forest environments (because they are not advantageous)

Question 3

stabilizing selection

Answer 3

Type of natural selection in which the population mean stabilizes on a particular non-extreme trait value.

Question 4

directional selection

Answer 4

A mode of natural selection in which an extreme phenotype is favored over other phenotypes, causing the allele frequency to shift over time in the direction of that phenotype.

Question 5

disruptive selection

Answer 5

Describes changes in population genetics in which extreme values for a trait are favored over intermediate values. In this case, the variance of the trait increases and the population is divided into two distinct groups.

Question 6

coevolution

Answer 6

the evolutionary change in one species is responded to by a change in a second species and so on

-i.e. a cheetah evolves to run faster, the monkey evolves to run faster

Question 7

diffuse coevolution

Answer 7

• coevolution between one species and a suite of other species
• ex. dung beetle moving many species of seeds in DUNG

Question 8

What are strategies/adaptations for coevolution not occurring?

Answer 8

in DUNG beetle:

Make seed bigger - cost, more energy and attractive to mice on forest floor

Change shape of seed - dung beetle wouldn’t want to have that in their ball

Question 9

group selection

Answer 9

-groups differ in attributes and these differences relate to differences in group survival

Question 10

sexual selection

Answer 10

-a component of individual selection that is created by the pressures that males and females exert on conspecifics as they compete for mates

• male-male competition
• female choice

Question 11

kin selection

Answer 11

• selection operating between closely related individuals to produce altruistic behaviours
• helps your genetic success bc your kin have some of your genes

Question 12

inclusive fitness

Answer 12

-a measure of total genetic success via personal reproduction (direct fitness) and effect on reproduction of non-descendant kin (indirect selection

Question 13

anagenesis

Answer 13

• a single species that evolves into another species over time
• aka chronospecies

Question 14

cladogenesis

Answer 14

• a single species evolving into two or more species over time
• increases diversity

Question 15

allopatric speciation

Answer 15

-speciation with a physical barrier (e.g. a river) that prevents gene flow and allows two populations to diverge

Question 16

sympatric speciation

Answer 16

-speciation without a physical behaviour, rather a behavioural or ecological barrier exists

Question 17

why might the theoretical ideas behind “coevolution” be important when considering the conservation of a species

Answer 17

• well these species are dependent and in a system with one another
• one change will affect other aspects of the population