Lecture 10 - Communication

Question 1

Spotted hyenas displaying

Answer 1

female pseudopenis

• evolved = high levels of male hormones to kill siblings, larger as adults
• now = signalling

Question 2

Cumulative selection - Richard Dawkins

Answer 2

selection builds up

can reach extreme in 40-70 generations

Question 3

Sensory modalities

Answer 3

auditory - ravens
UV - blue tit
tactile - chimps, pick off parasites
olfactory - luna moths, detect pheromones

Question 4

Sensory exploitation

Answer 4

biasing effect of existing perceptual mechanism on origins of new communication signals
- traits bias future evolution

Question 5

examples of sensory exploitation

Answer 5

cuckoo chick and reed warbler host
- cuckoo mimics whole brood begging intensity = high feeding rate

ground nesting species = higher frequency calls, harder for predators to hear

Question 6

Honest signalling

Answer 6

beneficial but costly
only good quality indvs can afford to produce it
can’t be faked

Question 7

Communication between bees and plants

Answer 7

nectar guides in plants for insects e.g. Azalea, eyebright
bees see yellow ans UV well
horse chesnut = nectar guides only yellow while pollen lasts

Question 8

Human waist to hip ratio

Answer 8

reproductive and long term health

men prefer normal weight with low WHR