Concepts

Question 1

Batesian mimicry

Answer 1

animal species that closely resemble poisonous species, but aren’t poisonous themselves

Question 2

Mullerian mimicry

Answer 2

heliconious and other butterfly species in central America mimic each other but are all distasteful

Question 3

Phenotypic variation

Answer 3

phenotype - what you see
product of interactions between genetic makeup
- genotype can have strong affect

Question 4

Developmental plasticity

Answer 4

genetically controlled response to environmental variation

Question 5

gene flow

Answer 5

movements of individuals are common and can result in movement of genes between pops.

• repro. and fert. involving dispersing gametes can cause departures from h-w equil = if donor population has a diff genetic structure from sink pop.
• may be swamped by gene flow through immigration where selective regime is diff

Question 6

mutation

Answer 6

rare -
procides great evolutionary potential
changes in base pair sequences in DNA of alleles

Question 7

genetic drift 1

Answer 7

Population bottlenecks are caused by catastrophic declines in numbers

• result in random total losses of rare mutations from populations and changes in allele frequencies: i.e. evolution!
• e.g. all cheetahs have the same mtDNA base pair sequence: evidence of a past bottleneck
• e.g. greater prairie chickens in Illinois declined from 100 million in 1900 to <50 in 1990’s: low genetic diversity is now reflected in low reproductive success

Question 8

genetic drift 2

Answer 8

If populations remain small they stay in a bottleneck

• Allele frequencies can then change dramatically and randomly, as a result of ‘gamete sampling error’
• Random (non-adaptive) evolution can result, especially in small populations

Question 9

non-random mating

Answer 9

Pollen transfer by visiting insects is to the other type because pollen is carried on head (pin) or abdomen (thrum)
- ‘Selfing’ in many flowering plant species produces populations in which homozygotes are over-represented compared to H-W equilibrium expectation

Question 10

Biological species concept

Answer 10

implies that individuals in different species can’t interbreed

• plants reproduce asexually
• nematodes, rotifers self fertilising hermaphrodites

Question 11

Ecological species concept

Answer 11

each species has discrete ecological niche defined in diff ways, and diff from all other species
- ecological niche of a species can represented as an n-dimensional hyperspace

Question 12

Phylogenetic species concept

Answer 12

Bacteria and other cryptic species (pipistrelle bats) can only be distinguished by call or DNA sequences
- organisms within species have discrete evolutionary history