Lecture 14 - the evolution of communication Flashcards

1
Q

2 examples of deceptive communication

A

1) cuckoo chicks decieve hosts into feeding it

2) moths can mimic hornet/wasps warning colous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

example of sexual deception in flowers

A
  • fly and bee orchids - decepts the male of the species into mating with a female because their flower petals look like a female - way for the orchid to be pollinated
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

example of sexual deception in fish

A

young male blue gill sunfish deceive older males by pretending to be females and sneak onto the territory to gain extra fertilisations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

example of sexual deception in a spider

A
  • bolas spider attracts male moths by mimicking female moths pheremones - this works because the balance of probability that there is gonna be a female at the end of the pheromone trail is higher than the likelihood it will be a spider - the spiders cash in on this
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

define sexual selection

A

Female choice selects for male traits that persuade females to mate with them…. This leads to a co-evolutionary arms race between the sexes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what are the 3 main ways that animal signals may be honest/reliable according to maynard smith and harper

A

1) common interest
2) handicap/ cost
3) index of quality (uncheatable signals)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

example of honest communication due to common interests in honeybees?

A

waggle dance - signal to other members of the colony direction of high quality food source

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

example of honest communication due to common interests with learned cues

A
  • long tailed tits - cooperative breeders - their calls are individually distinctive - helpers assist relatives - calls carry a kinship signal because you learn the calls from your parents- allows discrimination from kin to kin

this is an example of ‘environmental’ cues to kinship

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

example of honest communication due to common interests with genetic cues

A

’ green beard’ genes in fire ants

  • all egg laying females are Bb- bb females die prematurely
  • BB females are killed by Bb workers
  • Bb look out for other Bb so they can lay eggs
  • it it thought they recognise each other by odour cues (phenotypic effect)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what does a ‘green beard’ gene do?

A

1) Causes a phenotypic effect
2) Permits recognition of itself in other bearers
3) Causes differential behaviour towards bearers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

who proposed the green beard gene idea?

A

Richard Dawkins - proposed in his book the selfish gene - the idea that you are nice to other individuals with the same gene

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is an example of unrelated common interest communication?

A

raven yelling - ravens feed on carcasses - they are dependent on them in the winter to survive - they make a specific call indicating where the carcass is to other ravens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

why is raven yelling an example of honest communication?

A

because normally it would not be within their interest to share the food they have found with others but it is a technique they use when the food is on another ravens territory to overwhelm them so the territory holders couldn’t repel them - honest communication favoured by common interests

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what were the 3 initial hypotheses for why ravens yell?

A

1) Attract a “carcass opener” such as a bear (and incidentally more ravens)
2) Selfish herding: attract more ravens in case of predator attack
3) Overwhelm defence of territory holding ravens - the correct hypothesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

another way an animals signal may be honest/reliable is through it being costly/ a handicap to them- what is an example of this?

A

chicks begging

  • Parents often give more food to chicks that beg more
  • Begging calls can attract predators
  • the more food received by a chick the greater probability of survival
  • survival curve shows that hungry chicks benefit the most from begging
  • chicks dont constantly beg because the nests are more likely to be predated and it is an energetically costly process
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what experiment proved begging to have an effect on predation?

A
  • Artificial nests were more likely to be predated when begging calls played
  • the begging of tree nesters, attracts more predators than the begging of ground-nesters - Predation risk is lower in trees than on the ground, so tree nesters beg more loudly
  • the ground nesters have a high frequency beg (high frequency sound doesn’t travel as far)
17
Q

what effect does relatedness have on begging?

A

the cost of begging is less if you are less related to siblings - positive correlation between begging loudness and extra pair percentage

18
Q

a honest costly signal can also be in terms of display explain this

A
  • higher quality males have a higher probability of survival than low quality
  • the signal reduces survival because is it energetically costly to carry a heavy ornament/big display
  • females attracted to displays so mating increases
    display = honest signal of male quality
    = handicap that only high quality males can afford
19
Q

another way animals signals can be honest is by the the signals being uncheatable - give an example of this

A

in toads - the deeper the call the bigger size of the male and better their ability to deter rivals - honest signalling to females as they call to attract them

20
Q

some animals can cheat body size up to a point - give some examples of how they can do this

A
  • Inflating abdomen
  • Puffing out chest
  • Making hair stand on end
  • Elongating larynx to make deeper call