Behavioural ecology

Question 1

What is fitness defined as?

Answer 1

The success of an organism to contribute offspring to future generations

Question 2

What is the phenotypic gambit?

Answer 2

The assumption that genetic architecture is not constraining or inhibiting evolutionary trajectories

• simplifying assumption in evolutionary biology, particularly in evolutionary game theory, that the evolution of a trait’s phenotype (observable characteristics) can be analyzed without knowing the details of the underlying genetic architecture

Question 3

What are proximate and ultimate questions?

Answer 3

Ultimate questions ask about the behaviours evolutionary significance. (why and when?)

Proximate questions ask about the immediate cause of a behaviour. (how and what?

Question 4

What are tinbergen’s four questions?

Answer 4

Ontogeny (how it works across time)
Mechanism (how it works at one time)
Phylogeny (how it came to be across time)
Adaptive significance (how it came to be at one time)

Simply:
Development
Causation
Evolution
Function

Ontogeny is the process of development fertilisation to maturity

Question 5

How can we test if behaviour is inherited?

Answer 5

1. Correlation between parents and offspring - common garden experiment
2. Cross-breeding experiments
3. Artificial selection experiments
4. Molecular underpinnings

Question 6

How did the tests for inheritance work with blackcap migration?

Answer 6

1. Correlation: nestling raised in captivity still showed migratory restlessness in the direction of their parents (Austrian vs German)
2. Cross-breeding: Austrian and German hydrid went directly south (middle of two species directions)
3. Artificial selection: Migratory birds appear to be shorting routes or losing migration in response to climate change

Question 7

Give some info about animal decision making

Answer 7

• Simple decisions can affect an animals chances of survival and reproduction
• Decisions are shaped behaviours by natural/sexual selection
• Behaviour is often heritable and can be plastic
• Decisions often represent trade-offs

Question 8

Describe how great tits use adaptive decision making with respect to sparrowhawk populations

Answer 8

Great tits have an optimal body mass that balances the trade-off between hypothermia in the night and speed for escaping predators.

Individuals changed behaviour to balance risk of starvation with risk of predation, when sparrowhawk populations dipped in response to DDT, there were many more fat sparrowhawks.

Question 9

Why do animals form and maintain groups?

Answer 9

It is proposed that group living is a trade-off where benefits > costs, this will lead to an optimal group size

Benefits include direct and indirect fitness

Question 10

What are benefits of grouping?

Answer 10

• Anti-predator benefits
  The dilution effect (safety in numbers),
  The confusion effect (harder to attack large group),
  Shared vigilance (many eyes on predator allows earlier detection)
• Foraging benefits
  Lower individual level vigilance yet higher flock vigilance
  Cooperative hunting
  Information
  Learning
• Reproductive benefits
  Cooperative breeding (more info on later card)

Question 11

How do groups share information?

Subsection of benefits of grouping, foraging benefits

Answer 11

• Local enhancement: individuals are attracted to others at the foraging site
• Information centre: like a communal roost, tested in ravens
• Social networks: birds more central in social network were more likely to receive information - continuous spectrum of sociality

Question 12

What are the costs of grouping?

Answer 12

• Competition: more individuals means more competition for resources - food, breeding sites and reproductive opportunities.
• Disease and parasites: large groups vulnerable to infectious diseases - related to urban densitiy and social network ties e.g tassie devils
• Predation: Groups may be more conspicuous to predators - bait balling

Question 13

How do animals overcome the group cost of competition?

Answer 13

More scramble competition is resolved by ideal free distribution which says that individuals should aggregate proportionally to the amount of resource available.
Dominance heirachies benefit individuals by reducing uncertainty, lowering the number of necessary fights between individuals.

Question 14

Define altruism

Answer 14

Altruism benefits another inidividual at cost to oneself

Question 15

Explain kin selection

Family altruism

Answer 15

Parents can be selected to care for offspring due to shared genes. Kin selection favours behaviour that helps genetic relatives.
The coefficient of relatedness, r, is a measure of the proportion of genes shared by descent by two indivuals

Question 16

What did Hamilton’s rule show

explaination not equation

Answer 16

Altruistic behaviour is more likely to evolve the closer the relatedness of the donor to recipient.

Question 17

What is an example of kin selection?

Answer 17

Belding’s ground squirrels give alarm calls to warn others about predators. Calls are mostly given by females which have more relatives nearby.

Prairie dogs alarm call when more kin is in the group.

Question 18

What is a definition and example of cooperation?

Answer 18

Cooperative behaviour is when species work together for a common goal - both are benefited

Question 19

What is reciprocal altruism?

Answer 19

A form of cooperation where one individual A helps another B on one occasion (altruism) and B later reciprocates (hence reciprocal altruism)

Often called “tit for tat” - formalised through game theory though experiments like prisoners dilemma.

Seen in predator inspection by guppies

Question 20

How does the prisoners dilemma tie into reciprocity?

Answer 20

Prisoner’s dilemma explains why over repeated interactions, you will stop defecting (throwing the other person under the bus) because you might be punished.

A build up of trust allows maintained cooperation

Question 21

What is cooperative breeding, and what are the different types?

Answer 21

Cooperative breeding usually occurs when offspring help their mother raise their siblings but can be:
* Obligate cooperative breeders where they are unable to breed alone or in pairs (meerkats)
* Facultative cooperative breeders where the pairs are occassionaly helped (fairywrens) if dispersal is limited.
* Eusocial where helpers are sterile for their entire lives: helpers can derive both direct and indirect fitness - enhanced with haplodiploid organisms

Question 22

Define direct, indirect and inclusive fitness

Answer 22

• Direct: paying rent or social integration (helps your survival or your offspring survival)
• Indirect: kin selection benefits from helping
• Inclusive: The sum of direct and indirect fitness

Question 23

What is the signal theory of communication?

Answer 23

Signal theory says that communication is when a sender uses specially designed signals to modify the behaviour of intended recievers

• Signals benefit the sender
• Signals can target any senses or can be multimodal
• Signals evolve through ritualisation
• Different to cues

Question 24

What information does communication give?

Why communicate?

Answer 24

• Information about the sender: identity, sex, quality, reproductive state, toxicity e.g poison frogs
• Information about the environment including:
• Predators: Inform group members of danger, signal to predator it shouldn’t eat you, inform predator it is discovered, communicate info about predator.
• Food: bees waggle dance to signal location of food

Question 25

What does it mean that signals can be **referential**?

Answer 25

Signals can be subject to decision making rules, or signals can depend on context. * Vervet mokeys make calls specific to the kind of threat: Snake (look down), eagle (look up and run), leopard (climb trees) * If there is a cost to signalling, animals often decide when to signal based on context and recievers e.g alarm calling only to kin

Question 26

What are honest signals?

Answer 26

Signals that are a statistically reliable predictor of something about the signaller.

Question 27

What keeps signals honest?

Answer 27

* **Index signals** are signals that can't be faked. * Some signals are **limited by the condition** of the signaller. * **Habituation** can also keep animals from continuously producing dishonest signals * **Punishment** could keep signals honest but there is less evidence for this. Index example: frog call depth is tied to vocal system and size Conditional example: Ectoparasites reduce brightness of bird plumage Habituation example: Drongos and meerkats, drongos must vary their signals between honest and types of dishonest to avoid this habituation

Question 28

What is an example of a dishonest signal?

Answer 28

**Batesian mimicry** where animals that aren't toxic mimic the signals of those that are to fool predators. e.g frogs

Question 29

What is animal cognition?

Answer 29

**The mental capacities of animals.** Can include perception, individual and social learning, memory and some decision-making processes. It also includes some aspects of behavioural flexibility and meta-cognition. It integrates functional explanations of behaviour with an understanding of the underlying neural and physchological mechanisms.

Question 30

What is cognitive ecology?

Answer 30

Cognitive ecology seeks to understand how cognitive traits and general cognition has evolved in resporse to evironmental and social pressures.

Question 31

What are the types of cognition?

Answer 31

* **Spatial cognition**: the study of how animals learn and memorise routes and locations * **Memory**: the study of retention of learnt behaviour * **Problem-solving**: also known as animal innovation * **Physical cognition**: the study of how animals acquire and use information about the physical world including tool use * **Social cognition**: the study of decision-making rules that animals use when interacting * **Social learning and cultural**: the study of transmission of behaviour between individuals, within and between generations

Question 32

How is cognition measured?

Answer 32

Relative brain size (within taxa only) Neuron counts in brains Cognitive performance

Question 33

Can cognition be inherited?

Answer 33

Evidence from wild tits suggests that better problem solvers can raise larger broods for less effort, however they are also more likely to abandon their brood. The genome suggests it could be, as there is an overrepresentation of genes related to learning and cognition in regions under positive selection.

Question 34

How does artificial selection work in guppies

Answer 34

Big and small brain guppies do better (diversifying) Trade-off between gut size and brain size

Question 35

What are the consequences of cognition?

Answer 35

Cognitive buffer hypothesis - large brains allow animals to adaptively mount quick, flexible behavioural repsonses to frequent or unexpected environmental change

Question 36

What are proposed reasons for the evolution of flexible cognition?

Answer 36

* **Social intelligence** hypothesis (playing politics!) * **Cultural intelligence** (social learning and retaining socially shared knowledge) * **Technical intelligence hypothesis** (tool use, extractive foraging) * **Ecological intelligence** hypothesis (better diets, and remembering whether food is) * **Variable environments** hypothesis (copying with unpredictable environments)

Question 37

What are primary vs secondary sexual characters?

Answer 37

Primary sexual characters are essential for reproduction, secondary sexual characters are not. Secondary sexual characters are usually the outcome of sexual selection

Question 38

What is trivers parental investment theory?

Answer 38

Mating systems are determined by how much parental investment is required for successful raising of offspring.

Question 39

What is intra-sexual selection?

Answer 39

Competition among members of the same sex for access to the opposite sex. This most commonly takes the form of male-male competition.

Question 40

What is inter-sexual selection?

Answer 40

Choices by one sex among members of the opposite sex. Females are usually the choosier sex. (Note: “intra-” means within, and “inter-” means between.)

Question 41

Define male-male competition

Answer 41

Males compete with each other in many ways to maximize reproductive success. Eg: red deer males are selected to be large and have weapons to enable fighting for access to females.

Question 42

Define female choice | of resources or parental care

Answer 42

Females may choose among males on the basis of resources that they have to offer, and therefore clearly benefit from being choosy. For example, hummingbirds pick males dependent on the quality of their territory, and female house finches prefer brighter males, who are better at providing parental care.

Question 43

Female choice of ornamented males? | why

Answer 43

Females often prefer males with extravagant displays, for example male peacocks. The question of what females gain by such choices has been one of the most controversial in evolutionary biology.

Question 44

What are some reasons females might choose ornamented males?

Answer 44

**Good genes** indirectly choosing males with the best genes as they need to survive with crazy traits **Attractive genes** by choosing a showy male, a female's sons may inherit showiness and so enjoy a high reproductive success e.g. runaway selection with tail length in widowbirds **Can be a combo of both**

Question 45

How can females be subject to sexual selection?

Answer 45

* **Genetic correlation**: conspicuous female traits have evolved as a genetically correlated response to selection on males * **Direct selection**: selection that directly favours conspicuous female traits * **Female contest competition** * **Male mate choice** * **Mutual mate preferences**: various combinations of choosiness in the two sexes are possible, depending on costs and benefits.