Behavioural Ecology Flashcards
Explain difference between proximate and ultimate causes of behaviour.
Perhaps use red squirrels or butterfly/moth eyespots as examples
Proximate describes HOW organisms act this way such as their mechanisms and development (ontogeny).
Ultimate describes the root cause, ie. the WHY. This looks at the evolutionary cause and tje function (selective pressure)
What are these 2 main proximate causes for animal behaviour:
1. G——dev——– mechanisms
2. Se——-mo— mechanisms
Try and give examples of these.
- Genetic-devleopmental mechanisms: Such as effect of heredity on behaviour, sensory-motor system development through their environments
- Sensory-motor mechanisms such as nervous systems, hormone systems and skeletal-muscular systems for the response
What did Tinbergen (the creator of the ultimate / proximate causes) do to the wolf-bee? Wa this testing a proximate or an ultimate hypothesis?
Baffled it by moving pinecones away from it’s nest hole when it was out hunting to see if it did indeed circle to identify landmarks before it left home. Tested an PROXIMATE hypothesis.
What was Tinbergen 19– doing with all those eggshells? Was this testing an ultimate or a proximate hypothesis?
- Tested an ULTIMATE hypothesis by seeing that gulls did indeed move eggshells further away from their nests to reduce chick mortality from crows finding their nests.
https://brill.com/view/journals/beh/19/1-2/article-p74_3.xml
What was the experimental design for Vallin et al. 2005 study on Peacock butterflies.
One had no eye spots and sound.
One had eyespots and no sound
One had both
One had both and control paint around the spots
One had niether
One had both and control chunks taken out of the wings.
What were the findings of V—– et al. 20– studies on Peacock Butterflies.
Vallin et al. 2005: Eyespots were what mattered to reduce bluetit predation. Hissing did not matter for bluetits much at all. Hissing may be for bats.
How can we identify the evolutionary history of behaviours?
Can use Apidae bees as an example
Apidae bees.
You look at living members of the phylogeny and see which ancestors share this behaviour. Sometimes they appear to have evolved this behabviour convergently. As we must use the most PARSIMONIOUS methods with phylogenies, this can mean that we have got the phylogenies wrong, as perhaps with the Apidae bees, where swarming n nectar storing seem to have evolved twice, in them and in the honeybees
Which of these bees swarm? Which of them are eusocial? Which transfer nectar?
Euglossinae - Orchid bees
Apinae - Honey bees
Bombinae - Bumble bees
Meliponinae - Stingless bees
All but euglossinae are eusocial
Apinae and Meliponae both show swarming and nectar transfer from foragers to reciuevers.
Eusociality appears to have a single evolutionary origin, but problematically swarming & nectar transfer appear to have evolved twice in apinae and then meliponae. Bombinae evolved before meliponae confusing the phylogeny.
There are many proximate and ultimate hypothesis as to why humans eat sweet things. Give a couple.
These things taste sweet and nice - Proximate
Sugar is an energy source - ultimate
Our ancestors depended on sugar-rich fruits and we inherited them - Ultimate
Our genes shape the development of nerve cells that perceive sweetness and pleasure - Proximate - DEVELOPMENT of nerve cells
The sensory input from taste in the tongue to brain cells reinforces sweetness - Proximate and mechanistic.
Why do Hanuman langars likely commit infanticide?
A new dominant male will commit infanticide to father it’s own children sooner before being overthrown.
Group selection suggests populations with more s–r—– individuals would survive better. Group selection would thus be favoured if i—- compeititon is important and if groups are relatively l–l—– in relation to individual lifespan
self-restraining, intergroup, long-lived
Infanticide is also found in l—, giant w—- and j—–. The last 2 examples are committed by the females.
lions, waterbugs, jacanas
How did Young & Clutton Brock 2006 add to Bell et al. 2014 study on meerkats
Showed that dominant female litters less likely to survive is subordinate females have pups at the same time, thus infanticide made sense
Young and Clutton-Brock 2006 showed that if s—– AND d—— pregnant, litter survival went down even further to –%
subordinate, dominant, 10%
Why may honeybees sacrifice themselves with their stings?
Honey bee workers rarely reproduce anyway
Sacrifice saves their reprodiuctive investment
When sting is impeded, pheromone alerts other bees of intruder to protect nest.
Why may —— fish change sex?
Anthias fish. If NO dominant male, a female stepping in to take his place can suddenly increase her chances of reproductive success
How do garden spiders reduce risk of being Consumed during sex? 2 ways
- Nuptial gifts
- Crab spider may tie down female
The R—– spider shows some unusual behaviour. Why?
The male will place himselves in the (much larger) females jaws as iti is shown that canibalised males copulate longer and have higher paternity than those which do not.
- Mayliane Andrade studied this.
Search images in animals:
How did bluejays react when shown 2 different species of criptid moth compared to just one?
Improved when presented with images of 1 species, not both
What did Tinbergen observes about Passerine birds (bluetits and that) and search images?
Tinbergen observed that when a new type of caterpillar appeared in woodlands, birds rarely brought it back to nest. When a couple had been found, many more collected then.
Thus hypothesised the birds were building up a search image.
What did young skunks show us about how they find food by smell?
Could find & detect food from longer distances as they gained experience
Looking at lizard phylogenies can show us when vision/a—- foraging and olfaciont/s—– foraging diverged. A rooted o—- is used for comparison
ambush, searching
How are social insects and other group animals different in their foraging techniques? D——– Vs i——- foraging
- Insects are related. Wolves and such often aren’t.
- Insects use deliberate communication
- Wolves and such use incidental communication instead (watching foragers). They can thus take on prey bigger than themselves.
K— v– F—- investigated the waggle dance.
The r—– dance is done if food <50m
The f—–of e—– dance is done if food is >50m.
D—— obtained by angle of bee on vertical cones transposed to the sun.
D—– is obtained on how long it takes to perform dance
Karl Von Frisch, Round, Figure of eight, Direction, Distance
Karl Von Frisch saw how bees communicate distance by creating irregularly p—– tunnels to confuse bees. These bees thought the distance was l—— than it actually was so did significantly less r—- dances. Thus we know bees use visual cues to determine distance. What mechanism did bees do this by\?
patterned, longer, round.
- Showed that it was a NEUROMECHANISM in bees which was used to infer distance
T/F bee foragers found food faster when waggle dance was used.
FALSE, just found better QUALITY food. Thus colony only benefits from this behaviour in winter when prey is scarce.
How do researchers know that ospreys rely on eachother for direction of a fish shoal?
Saw that signifiantly more ospreys headed off in the direction of one which has eeturned with an alewife fish than just a random one.
Informed birds found food faster than naive ones.
Why don’t swallows benefit from getting ‘help’ finding prey? Clue: t—— e—-
Their prey is TEMPORARILY EPHEMERAL. Flies move about loads.
Why don’t groups of female lions and other hunting carnivores disband in times of food scarcity, even though their strategy stops being useful then? Who studied this on what species
Creel & Creel hypothesised that it may REDUCE energy cost from chasing prey etc. African wild dogs DFO show that net energy gain INCREASED in larger packs.
Special reading 2: B— et al. 20–, Suppressing subordinate reproduction provides benefits to dominants in cooperative societies of meerkats.
What did they do to maje this study?
What did they find?
Bell et al. 2014
They used contraceptive injections to stop subordinated reproducing
Weight and health of dominant meerkats pups then shown to significantly increase.
Showed that doms benefitted when they were aggresive to subs to stop them reproducing.
Foraging more effective & aggression lower when subs had no pups.
Showed this behaviour was indeed an adaptive strat for the dominant meerkats.
Special Reading 3: D— et al. 20–. About sand goby and infanticide.
1. When do male sand gobies commit infanticide?
2. Why do they?
3. What does this show?
Deal et al. 2017
1. Signifcantly more likely to when shown more ‘predator cues’. Reduced offspring investment & effort attracting mate.
2. When predators around, prioritise own survival thus may engage in filial cannibalism
3. Shows role of dangerous and uncertain environments in eliciting different levels of paternal investment in this species.
What is sexual deception? Give an example.
Mimicing a sexual signal of another species to exploit it. Such as the Bolas spider using female moth pheromones to attract the male.
Name the 3 main ways in which communication can be honest
- There are common interests in which both parties benefit.
- There is a cost to the signal given out.
- The signals are an index of quality which CANNOT be cheated.
How does common interest communication cause ravens to yell?
Yelling at a carcass if you were NOT in your own territory attracted other non-resident ravens and stopped territory holder from repelling all the others.
Tested by leaving carcasses in woods and observing that the resident ravens did NOT yell if they found a carcass.
How does a cost for communication stop chicks always begging?
Tested on fake nests. A well-fed chick would bhave a SMALL increase in survival for the same amount of food if it kept begging when full. Thus it would not be worth the predation risk to keep squawking when full.
Under what conditions do bird chicks beg louder?
- If this bird species shows extra-pair parentage, so brrod less closely related.
- If brood parasites are present.
In both of these examples, there is a lower risk of their relatives being eaten. - If they are a tree-nesting species.
Ground nesting birds shown to beg at a ——- frequency perhaps to be less hearable to predators than tree nesting ones.
higher
Why are sexual ornaments in bird species often honest signals of quality?
It is more costly for low quality males to show snazzy ornamentation. Thus it is only an affordable option for the high quality males.
How do certain toad calls give evidence of honest communication due to uncheatability?
Stuyd have shown that bigger toads of a species produce deeper calls, making them an honest signal for male size & ability deterring rivals.
How can species cheat honest communication of size, to an extent?
Inflating abdomen, puffing out chest, making hair stand on end, elongating larynx to make a deeper call.
Hamilton’s rule evolved around the idea of i—– fitness for a species. Under this rule, a behaviour was favoured if c<br.
What are the letters in this equation?
inclusive fitness
c= cost of behaviour to actor
b = benefit to recipient
r = relatedness
In Hamilton’s rule, what is an example of a positive c and b ?
Giving AWAY food
So STEALING food would therefore result in negative values
Under what 3 conditions can cannibalism in the Tiger Salamander evolve?
- Many members of species in population.
- Variation in larval size, so lots of small ones around to eat
- Mostly UNRELATED individuals.
Under Game Theory, why does the sex bias end up around 50:50 eventually?
It is of benefit to the parent that their offspring stand the best chance of producing grand-offspring.
They have the best chance of doing this if population has around a 1:1 sex ratio.
If a species can choose offsprings sex and there are lots of females currently, they may produce sons.
This would fluctuate, and overtime it’d be the best ESS for all broods to be around 50:50 between the sexes.
What does ESS stand for?
An Evolutionary Stable Strategy
Under Game Theory for sex ratios, what an i—– of a species is doing depends on what o—- members of the population are doing
individual, other
Definition: One indivdual directly interacting with another individual for a resource
Pairwise Contests. Thought up by John Maynard Smith
Hawk-dove interactions:
Hawks get …
Doves get …
all or nothing
less, or nothing when a hawk is there
Doves can win against hawks when c>v. What does this mean?
Doves can win against hawks when fighting cost is greater than the resource itself.
Hawks win against doves when v>v/2. What does this mean?
Hawks win against doves when resource to hawks is greater than the resource the doves get on their own.
What happens to the hawks and the doves if c>v and v>v/2 are both true at the same time?
We can get a mixed ESS
In the b—— strat within hawk-dove theory, an individual plays —– when it is the OWNER / RESIDENT of the resource but —- when it is an intruder
Bourgeois, hawk, dove
What are the 2 considered outcomes in rock-paper-scissors game theory?
- 1/3 of a population adopts each strategy
- Members of the popualtion cycle through each strategy, as demonstrated with male side-botched lizards of different morphs n mating strats.
John Maynard Smith introduced Pairwise Contests and he ALSO introduced the idea of o—– f—- theory, in which animals should ba;ance the benefits (energy) of getting a resource with the cost (time & effort) of adquiring it
optimal foraging theory
John Maynard Smith introduced Pairwise Contests and he ALSO introduced the idea of o—– f—- theory, in which animals should ba;ance the benefits (energy) of getting a resource with the cost (time & effort) of adquiring it
optimal foraging theory
What support did —- 1— find for optimal foraging?
Zach 1979 North-Western crows drop optimally sized whelks from the optimal height to get food.
Fill in these scenarios in which cost-benefit logic may NOT be met.
1. Animals — well adapted
2. Observations made were ——–
3. Important —— not considered in model
4. ——- were not valid
1.NOT
2. Innapropriate / unsuitable
3. Factors
4. Assumptions
How did oyster catchers show that an invalid assumption had been made under cost-benefit logic?
Oystercatchers initially predicted to go for largest mussel.
However, these cannot be opened.
Thus they went for an optimal size of 50mm instead.
Belovsky 1978. A classic study. What 3 constraints do moose need to balance?
Energy, rumen volume and sodium from food.
- Aquatic veg has high sodium and little energy.
- Trees have the opposite.
Thus moose eat both.
