10. Animal Behaviour

Question 1

What is Behaviour?

Answer 1

Behaviour is defined as a change in the activity of an organism in response to a stimulus (an external or internal cue or combo of cues)

– To fully understand a behaviour, we want to know what causes it, how it develops in an individual, how it benefits an organism, and how it evolved

Question 2

What are Innate Behaviours?

Answer 2

genetically hardwired

Question 3

What are Learned Behaviours?

Answer 3

developed through experience

Question 4

What is Behavioural Ecology?

Answer 4

Behavioral ecology is the study of the behavioral adaptations that evolved in response to ecological selection pressures

Question 5

What is Proximate Causation?

Answer 5

Proximate (or mechanistic) causation explains how actions occur

• Proximate mechanisms can be genetic, neurological, hormonal, immunological, and skeletal–muscular

For example, does a neural or hormonal signal trigger an animal’s courtship display? Does the courtship display vary according to diet, photoperiod, temperature, or other factors?

Question 6

What is Ultimate Causation?

Answer 6

Ultimate (or evolutionary) causation explains why actions occur

• Ultimate mechanisms are based on evolutionary consequences and history (behaviour is just like any other phenotype in that it can evolve by natural selection) – looks at the effects of behaviour on fitness, through an understanding of the ecology of the organism and its evolution
• For example, is a behaviour currently adaptive, meaning that it increases an individual’s ability to produce viable, fertile offspring? How does the behavior help individuals in a particular environment?

Question 7

Argentine Ant Behaviour

Originally from Argentina but are extremely invasive in many parts of the world

– In their native South America, Argentine ants live in colonies and defend territories by fighting with neighbouring Argentine ants

– In Southern California, where they have been introduced, Argentine ants in adjacent colonies are “friendly” to each other

o Ants (workers and queens) move from nest to nest and form large “super colonies”

– However, these ants are extremely aggressive to native ants

Answer 7

Proximate causes

– On a proximate level, ants identify each other via smelly waxy hydrocarbon “tags” on their exoskeletons

– The introduced Argentine ants have almost no genetic variation in the allele that gives rise to these scent tags

– Because of this, these ants cannot distinguish among colonies of other introduced Argentine ants, but perceive native ants and their unfamiliar scents as enemies

Question 8

Argentine Ant Behaviour

Originally from Argentina but are extremely invasive in many parts of the world

– In their native South America, Argentine ants live in colonies and defend territories by fighting with neighbouring Argentine ants

– In Southern California, where they have been introduced, Argentine ants in adjacent colonies are “friendly” to each other

o Ants (workers and queens) move from nest to nest and form large “super colonies”

– However, these ants are extremely aggressive to native ants

Answer 8

Ultimate causes

– Since Argentine ants in super colonies are not fighting to maintain their feeding territories, they have more time and energy available to produce offspring, thus increasing their fitness

– The resulting high density of the super colonies contributes to their invasiveness

– A single, tiny Argentine ant is rarely successful in combat against a single, larger native ant – but when Argentine ants recruit help and fight in mobs, they are a powerful force

Question 9

Innate vs Learned Behaviours

Answer 9

Learning is an enduring change in behaviour that results from a specific experience

Innate behaviour requires no learning - it is inherited and shows little variation based on learning or the individual’s condition

• So, innate behaviours tend to be more fixed and learned behaviours more flexible

– Innate example: the jump-back behavior of kangaroo rats when they hear the sound of a rattlesnake’s tail (the jump-behavior is performed the same way every time)

– Learned example: a rat can be trained to pull a lever if food is released as a reward

Question 10

Innate vs Learned Behaviour Chart

Answer 10

Question 11

What are 5 Types of Learning?

Answer 11

1. Imprinting
2. Spatial learning
3. Conditioning
4. Cognition
5. Habituation

Question 12

What is Imprinting?

Answer 12

Imprinting results in newborn animals bonding with their parent(s)

Question 13

What is Spatial Learning?

Answer 13

Spatial learning entails memorizing the features or layout of an environment, such as a maze, tank, or section of forest

Question 14

What is Conditioning?

Answer 14

Conditioning requires that an animal form an association between two events, such as a lever and food

Question 15

What is Cognition?

Answer 15

Cognition involves complex thought, which is evidenced in behaviors such as tool manufacture and use, language acquisition, and problem-solving

Question 16

What is Habituation?

Answer 16

Habituation is a simple form of learning in which an animal stops responding to a stimulus after a period of repeated exposure

NOTE – Stimulus is not associated with any punishment or reward

EXAMPLE = Prairie dogs typically sound an alarm call when threatened by a predator, but they become habituated to the sound of human footsteps when no harm is associated with this sound, therefore, they no longer respond to them with an alarm call

Question 17

What are Fitness Trade-Offs?

Answer 17

Each behaviour has different costs and benefits, resulting in fitness trade-offs, or inescapable compromises between two traits that cannot be optimized simultaneously

– For example, animals cannot maximize both the energy invested in finding food and in finding mates

Question 18

What is Cost-Benefit analysis?

Answer 18

To link condition-dependent behaviour to fitness, biologists use a framework called cost-benefit analysis

– Costs and benefits of behavioral decisions are measured in terms of their impact on fitness—the ability to produce viable and fertile offspring

Question 19

What are Two things to remember about cost–benefit analysis?

Answer 19

1. The choices made by non-human animals are not known to be conscious choices

For example
an Argentine ant does not sniff another ant and then ask, “Should I greet this ant as a friend or attack if they are a foe?” – instead, generations of natural selection have resulted in nervous and endocrine systems that are capable of taking in information and directing behavior that is likely to pass on to the next generation

2. The behavior of individuals varies within a population
   o Some individuals are more active, fearful, or social than others

Question 20

What is Optimal Foraging?

Answer 20

The hypothesis is that animals maximize their feeding efficiency is called optimal foraging

The concept of optimal foraging can be expressed as

Question 21

What is the assumption behind optimal foraging?

Answer 21

The assumption behind optimal foraging is that if animals maximize benefits and minimize costs, they will have more time and energy for reproduction and higher fitness