Introduction to Animal Behaviour

  • WageningenX: AB101x

Module 1: The Science of Animal Behaviour

Introduction

An interesting anecdote about an experiment by Niko Tinbergen in the early thirties, attempting to understand how beewolves find their way back to their tunnels. He placed pinecones in a circle around the tunnel, then moved them later, to see if the beewolves would search (incorrectly) at the center of the circle of pinecones. They did, leading to the conclusion that they seem to use landmarks for navigation. Numerous experiments were performed to work out additional details.

Module Overview Animation

Evolution is of key importance to the science of animal behavior.

Three main prcesses drive evolution:

  1. mutations, random changes in genetic material
  2. genetic drift, the influence of chance on whether an individual reproduces
  3. natural selection, the tendency for individuals better adapted to the environment to reproduce more

Tinbergen's 4 Whys:

  1. causation: what makes an individual show a certain behavior?
  2. development of behavior: how did an individual develop the ability to show this behavior?
  3. evolution: how did this behavior evolve?
  4. function and survival value: what is the function of this behavior?

The first two whys make up the proximate questions, related to causes, and the last two make up the ultimate questions, related to consequences.

Evolution and Natural Selection

Species that share evolutionary history should be similar, and by studying the similarities we can reconstruct their evolutionary relationships, called a phylogeny.

Not all similar traits are due to inheritence: sharks and dolphins look similar because of adaptation to the environment. Shared traits attributed to inheritance are called homologous, while those attributed to convergent evolution are called analogous.

Applications of Animal Behavior

The science of animal behavior has broad applications. For example, it improves our ability to raise animals for food or other products, to understand pets, to protect crops from destructive animals, to manage wildlife such as fish, and to understand humans--we are, after all, animals ourselves.

The 4 'Why' Questions

For the example of birdsong, the 4 Whys might look like

  1. Causation: Why is the bird singing? For territorial reasons? Hormonal? Environmental? And physiologically, how is it producing the song, and how does it organize the song?
  2. Development: How did the bird come to sing as it does? Did it learn the song? Did it practice in order to be able to sing well?
  3. Function: What is the effect of singing, its value? Does it allow a bird to defend its territory, or attract a mate, when singing in a particular way?
  4. Evolution: How did the singing evolve? How does the song relate to the song of related species? How did the song change along with the evolution of the species?

Understanding all four types of questions allows a more complete picture of the animal behavior.

The Scientific Method

We must form hypothesis and devises tests that may support or reject them.

The example given is: why do cats scratch at closed doors? Hypotheses: 1) cats want to go through the doors 2) cats are sadists. The first is easy to test; the second, not so much.

Discussion: Animal Welfare

An interview with Dr. Bas Rodenburg, associate professor at Wageningen University who researches animal welfare, with a particular focus on production animals.

We can study animal welfare by examining the system in which the animals are kept--how much space they have, how much access to food, etc.--as well as by investigating the animal itself, checking for signs of its health and happiness.

In the example given, the goal of such research might be to develop designs for egg farms that reduce undesired behavior, such as cannibalism or injury.

One interesting fact was that animal mood is 'contagious': introducing a very happy and playful pig into a group caused the other pigs in the group to become more happy and playful.

Approaches to Studying Behavior

There are four main approaches to studying behavior:

  • observational studies
  • experiments
  • comparitive analyses
  • theoretical models

The observational studies involve observing the behavior of the animal without interfering. This can give good information about behaviors and relationships between them, but cannot determine causation.

Experiments allow us to test hypotheses about the causes of behavior.

Comparative analyses might compare the behavior of one species to the behavior of a related species, to understand how they might vary due to environmental or genetic factors.

Finally, theoretical models use our understanding of animal behavior to try to predict how animals will behave, and what the results will be. These predicitons can then be tested through experiments, and if the predictions were accurate, then the model is supported as a good desctiption of the animal's behavior.

Further Reading

One journal article is suggested:

Additionally, four books are recommended:

  • Ridley (2003) Evolution (3rd edition) Wiley-Blackwell.
  • Coyne (2010) Why Evolution is True. Oxford University Press.
  • Weiner (1994) The Beak of the Finch: A Story of Evolution in Our Time. Knopf.
  • Dawkins (2006) The Selfish Gene (30th Anniversary edition). Oxford University Press.

Finally, one web link:

Module 2: Learning, Cognition, and Development

Module Overview Animation

Behavior that is performed without any apparent learning is referred to as innate, instinctive, or unlearned behavior.

The simplest form of learning is called habituation. This form of learning is when the response to a stimulus is reduced as it is learned to be unimportant.

In associative learning, two previously unconnected events become linked, such as the assocation of the sound of a bell with food.

When individuals learn something through direct experience, such as by trial-and-error, this is called individual learning. When individuals learn something by observing others, such as a young learning to hunt by watching its parents, this is called social learning.

Whether learning occurs may be dependent on factors such as age, social status, sex, or personality. If an individual can reliably acquire food by stealing it from others, it need not learn to hunt.

Why do animals learn?

Learning enables animals to adapt to a changing or complex environment. We can expect behaviors to be learned when experience is valuable, and innate when experience is not important.

There are two main situations in which experience would not be important:

  1. If the environnment is fixed, then behavior need not be modified. Optimal behavior can be encoded as instinct.
  2. If the best response to a stimulus changes on each encounter, or if the stimuli are rarely encountered more than once, then learning has no benefit.

In the real world, usually environments will fall between these two extremes.

Learning can modify innate responses. For example habituation enables an animal to learn to ignore a certain stimulus that it would naturally respond to. The opposite, sensitization, enables an animal to learn to respond to a new stimulus that it would otherwise ignore.

The example given of habituation is the "dear enemy" effect in territorial animals. The effect is displayed when an animal reacts less aggressively to the territorial call of a familiar neighbor than to an unfamiliar individual. This habituation is useful because the familiar neighbor likely already has an established territory, and is unlikely to be a threat, whereas unfamiliar individuals may be seeking a new territory.

Learning by association

Animals respond to stimuli. We call those responses which are exhibited without any learning unconditioned responses, and those which occur after learning conditioned responses.

Associative learning is often divided into two fundamental types: classical conditioning and instrumental conditioning.

Classical conditioning, also known as Pavlovian conditioning involves making an association between a stimulus and a reinforcer, while instrumental conditioning or operant conditioning involves associating an action with a reinforcer.

The standard example of instrumental conditioning is the Skinner box, in which a rat is trained to press a lever in response to a stimulus in order to be rewarded with food.

Two opposite processes involved in learning are generalisation and discrimination.

Generalisation occurs when animals respond to stimuli related to the one that was learned, such as responding to different tones of bell than the one that was used during training.

Discrimination occurs when animals learn not to respond to similar stimuli, such learning to respond only to the correct tone of bell, rather than all similar tones.

Learning from others

When the performance of a behavior by an individual causes the same behavior in others, it is referred to as social facilitation. For example, blue tits seeing others opening milk bottles might learn to open them as well.

When the presence of an individual, without demonstrating a behavior, encourages others to learn the behavior, it is known as local enhancement. For example, a blue tit seeing others near a milk bottle might examine the bottle more thoroughly, and thus learn to open it.

When the traces left behind are enough to cause a novel behavior to propagate, this is called stimulus enhancement. For example, a blue tit seeing an opened milk bottle could learn to open the bottle itself.

Just because one individual learns from another, this does not mean that teaching is occurring. We can define teaching according to three criteria:

  1. An individual must modify its behavior in the presence of naive individuals in a way that facilitates learning.
  2. The teach should incur some cost as a result, such as additional time expenditure.
  3. The students should incur a clear benefit, such as learning more quickly than they would have without the teaching.

According to this definition, teaching has been observed in only four species: rock ants, meerkats, pied babblers, and superb fairy wrens. However, it should be expected, given the diversity of these species, that teaching does occur in other species.

Cognition and insight

Cognition refers to processes involving mental representations of the outside world.

A theory of mind is the ability of an animal to understand the mental states of other individuals as differing from its own. This ability appears in humans at around age four.

Solving novel problems without resorting to trial-and-error is known as insight. It requires some ability to plan ahead.

Measuring animal intelligence, such as with an IQ test, is difficult. Different animals will have their intelligence optimized for different problems, so results are not likely to be comparable. For example, a common element of human IQ tests is recognizing rotations of a figure as being equivalent. Pigeons outperform humans at this test.

Behavioural development

Behaviors deveop as a result of both nature and nurture. If two genotypes display different responses to environment, this is called a gene-environment interaction.

Animals can develop behaviors through play. We can define play as exhibiting behaviors in a non-functional context, that is, without any apparent direct benefit.

Three forms of play are:

  1. object play
  2. locomotor play
  3. social play

Object play, such as a dog playing with a ball, enable animals to practice foraging skills.

Locomotor play involves individuals running around in a seemingly playful manners, such as a young horse running around in a field. This can help develop motor skills.

Social play involves animals play-fighting and such, and enables animals to develop appropriate social responses for different interactions.

Play is normally performed when an animal is safe and unstressed, so it can be used as an indicator of animal welfare.

Stress and companion animals

Name Role
James Savage Instructor
Lysanne Snijders Instructor
Marc Naguib Instructor
edX Publisher