ZY3020 Animal Behaviour 1 - Module Introduction and History
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Defining Behaviour
Psychologists B.F. Skinner and D.O. Hebb:
"All observable processes by which an animal responds to perceived changes in the internal state of its body or the external world."
OED definition:
"Deportment, manners…moral conduct…way in which a…machine, substance etc. acts or works; response to stimulus."
Repeatable measurement:
Inherent consistency of many behaviour patterns allows reliable repeated observation. This enables researchers to collect quantitative data and conduct statistical analyses to identify patterns and relationships in animal behaviour.
Function of Behaviour Patterns
Behaviour patterns frequently have a functional outcome. This suggests that behaviours serve specific purposes in an animal's life, such as survival, reproduction, or social interaction.
Gives them an air of purpose. The functional outcomes of behaviours often make them appear as though they are performed with intention or goal-directedness.
Decision making: "hard-wired" vs flexible response? Animals may exhibit both innate (hard-wired) behaviours that are genetically programmed and flexible behaviours that are modified by experience and environmental conditions.
Goal Pursuit
Three ways of appearing to pursue a goal:
Goal-directedness:
e.g., Digger wasp – purposeful behaviour based upon an internal representation. Digger wasps exhibit complex behaviours that suggest an internal representation of their goals, such as finding and provisioning nests with prey.
Goal-achieving:
e.g., Woodlice – requirement for some commodity makes animal restless until goal is achieved. Woodlice exhibit goal-achieving behaviour by seeking out specific resources, such as moisture, and becoming restless until they are obtained.
Goal-seeking:
e.g., Domestic chicken – performance of the behaviour itself that is important. Domestic chickens engage in goal-seeking behaviours, such as pecking and scratching, which appear to be intrinsically rewarding, regardless of their immediate consequences.
Why Study Animal Behaviour?
To capture animals for food. Understanding animal behaviour is essential for effective hunting, trapping, and fishing practices, allowing humans to predict and exploit animal movements and responses.
To domesticate animals. Knowledge of animal behaviour is crucial for successful domestication, enabling humans to select and breed animals with desirable traits and manage them effectively in captivity.
To conserve animals. Studying animal behaviour is vital for conservation efforts, providing insights into habitat requirements, social structures, and responses to environmental changes, which inform management strategies.
To maintain well-being of captive animals. Understanding animal behaviour is essential for ensuring the welfare of animals in zoos, aquariums, and research facilities, allowing caretakers to provide appropriate environments and enrichment activities.
To answer academic questions:
e.g., function and evolution of behaviour. Animal behaviour research addresses fundamental questions about the origins, mechanisms, and adaptive significance of behaviour, contributing to our understanding of the natural world.
Research Questions in Animal Behaviour
What is its function (adaptive purpose)? Understanding the adaptive function of a behaviour involves identifying how it contributes to an animal's survival and reproductive success in its natural environment.
How is it initiated and controlled (mechanism)? Investigating the mechanisms underlying behaviour involves exploring the physiological, neurological, and hormonal processes that trigger and regulate specific actions.
How does it change or develop (ontogeny)? Studying the ontogeny of behaviour involves examining how behaviour develops over an animal's lifetime, including the roles of genetics, learning, and environmental influences.
What is its history (evolution)? Examining the evolutionary history of behaviour involves tracing its origins and diversification across different species, revealing how natural selection has shaped behavioural traits over time.
Migrating Birds Example
Questions one might ask:
Why do they do it? What are the ultimate reasons for migration, such as access to breeding grounds, food resources, or favorable climates?
How did it all begin? How did migratory behaviour evolve in birds, and what selective pressures favored its development?
What do they gain that outweighs the costs of such a journey? What are the benefits of migration in terms of survival and reproduction, and how do these benefits outweigh the energetic costs and risks involved?
Was sea temperature rise etc. responsible? How do environmental factors, such as sea temperature, influence migratory patterns and timing in birds?
Did migratory paths modify with time? How have migratory routes changed over time in response to environmental changes and other factors?
How do they "know" it is time? What cues do birds use to initiate migration, such as changes in day length, temperature, or food availability?
How do they find their way? How do birds navigate during migration, using cues such as the sun, stars, magnetic fields, and landmarks?
Do the first-time travellers inherit a directional tendency? Is there a genetic component to migratory orientation, such that first-time migrants inherit a general sense of direction?
Or do they learn directions from experienced travellers? Do young birds learn migratory routes from experienced adults through social learning and imitation?
Niko Tinbergen’s Four Questions (Four Whys)
Mechanism (causation):
How is the behaviour achieved? How do physiological, neurological, and hormonal mechanisms control the behaviour?
Concerned with how the system operates in terms of underlying mechanism and organization. This involves investigating the specific neural circuits, hormonal pathways, and sensory systems that mediate the behaviour.
Development (ontogeny):
How does the behaviour develop? How does the behaviour change over the course of an animal's lifetime?
Concerned with the way the system reflects its embryological, cultural, or other developmental influences. This involves examining the roles of genetics, learning, and environmental factors in shaping the behaviour.
Function (adaptive value):
What is the behaviour for? How does the behaviour contribute to an animal's survival and reproductive success?
Concerned with what the system is designed to do, i.e., its role in the life of the organism. This involves identifying the specific benefits that the behaviour provides to the animal in its natural environment.
Evolution (phylogeny):
Where has the behaviour come from? How has the behaviour evolved over time?
Concerned with the ancestral selection pressures and phylogenetic pathways that have shaped and constrained the system. This involves tracing the origins and diversification of the behaviour across different species.
Ultimate vs. Proximate Explanations
Functional explanations are sometimes referred to as ultimate explanations:
Concerned with the adaptive consequences of a behaviour and thus the reason ('why?') it has evolved. Ultimate explanations focus on the evolutionary pressures that have shaped the behaviour over generations.
Explanations in terms of mechanism are referred to as proximate explanations:
Concerned with the physical systems that influence the performance of a behaviour ('how?'). Proximate explanations focus on the immediate causes of the behaviour, such as physiological and neurological mechanisms.
Functional = ultimate (Why?)
Mechanism = proximate (How?)
Tinbergen's Four Questions - Table
Current
Mechanism (Causation) - Proximate (How?)
How does this behaviour occur in an individual? What are the immediate triggers and underlying mechanisms that elicit the behaviour in a particular individual?
Ontogeny (Development) - Proximate (How?)
How does this behaviour arise in an individual? How does the behaviour develop over the course of an individual's lifetime, and what factors influence its development?
Historical
Adaptive Value (Function) - Ultimate (Why?)
Why is this behaviour adaptive for the species? How does the behaviour contribute to the survival and reproductive success of the species as a whole?
Phylogeny (Evolution) - Ultimate (Why?)
How does this behaviour arise in the species? What is the evolutionary history of the behaviour, and how has it been shaped by natural selection over time?
Geese Imprinting Example
Behaviour: Young geese follow and imprint on their mother.
Proximate Cause (How?):
During an early, critical developmental stage, the young geese observe their mother moving away from them and calling. This critical period is a specific time in development when the young geese are particularly sensitive to learning and forming attachments.
Ultimate Cause (Why?):
On average, geese that follow and imprint on their mother receive more care and learn necessary skills, and thus have a greater chance of surviving than those that do not follow their mother. Imprinting ensures that young geese stay close to their mother, who provides protection, warmth, and guidance in finding food and avoiding predators.
Sparrow Song Example
A male sparrow is singing at dawn.
Cause (Mechanism):
Internal or external stimuli, i.e., mate is nearby. The singing behaviour may be triggered by hormonal changes, territorial intrusions, or the presence of a potential mate.
Development (Ontogeny):
Hatchlings do not sing; they learn to sing as they mature. Young sparrows learn their songs by listening to and imitating adult males, gradually refining their vocalizations over time.
Function (Adaptive Value):
Keep intruding males away from his nest?
Attract females? The song serves as a signal to other males, indicating the singer's territory ownership and willingness to defend it. It also serves as a display to attract females, demonstrating the singer's fitness and quality as a mate.
Evolution:
Song has evolved over time to become more elaborate to help with function (birds that sing correctly get mates and pass on their genes). Natural selection has favored males with more complex and attractive songs, as they are more likely to attract mates and pass on their genes to the next generation.
Addressing the Four Whys
Experimental approach: Conduct controlled experiments to manipulate variables and test hypotheses about the causes and functions of behaviour.
Observational studies: Observe and record behaviour in natural settings to identify patterns and relationships in the absence of experimental manipulation.
Comparative approach: Compare the behaviour of different species to identify commonalities and differences, providing insights into the evolution and adaptive significance of behaviour.
Theoretical models: Develop mathematical and computer models to simulate behaviour and test hypotheses about the underlying mechanisms and evolutionary pressures shaping behaviour.
All or combinations of the above!
History of Animal Behaviour
The beginnings with Darwin
Classical Ethology
Comparative psychology
Nature versus Nurture controversy
Sociobiology/Behavioural ecology
The Beginnings with Darwin
Darwin (1809-1882)
In his book The Descent of Man and Selection in Relation to Sex, he suggested that evolution would act not only on the physical characteristics of animals but also their mental abilities. Darwin's work laid the foundation for the study of animal behaviour by emphasizing the importance of natural selection in shaping both physical and behavioural traits.
Darwin's Contributions
On the Origin of Species:
Provides conceptual frame for Animal Behaviour. Darwin's theory of evolution by natural selection provided a framework for understanding how behaviour can evolve to enhance an animal's survival and reproductive success.
The emotions in man and other animals:
Included careful observations of animals. Darwin's observations of animal behaviour, particularly in the context of emotions, provided valuable insights into the similarities and differences between human and animal behaviour.
Limitations of Darwin's Observations
His observations were anecdotal and anthropomorphic. Darwin's interpretations of animal behaviour were sometimes based on subjective impressions and comparisons to human emotions, which limited the scientific rigor of his conclusions.
e.g., Dogs expressed anger, shame, and love. Attributing human emotions to animals without sufficient evidence can lead to inaccurate interpretations of their behaviour.
Early to Mid 1900s
Ethologists- Europe
Field-based research: Ethologists conducted their research in the natural habitats of animals, observing their behaviour in realistic contexts.
Evolutionary questions: Ethologists focused on understanding the evolutionary origins and adaptive functions of behaviour.
Comparative psychologists- America
Laboratory-based research: Comparative psychologists conducted their research in controlled laboratory settings, manipulating variables to study the mechanisms underlying behaviour.
Mechanism questions: Comparative psychologists focused on understanding the physiological, neurological, and psychological mechanisms that control behaviour.
Perceptions of Ethologists vs. Comparative Psychologists
Ethologists:
Zoologists interested in a wide range of species and species-typical ways they behaved. Ethologists were interested in understanding the diversity of behaviour across different animal species and how behaviour is adapted to specific ecological niches.
Comparative psychologists:
More interested in similarities, seeking general laws in behaviour. Comparative psychologists sought to identify universal principles of behaviour that apply across different animal species, including humans.
Classical Ethology
Niko Tinbergen, Konrad Lorenz, Karl von Frisch
Ethologists that received a Nobel prize for their contributions in understanding the proximate causes of behaviour. These three scientists made groundbreaking discoveries about the innate behaviours of animals and the mechanisms that control them.
Approach of Classical Ethologists
Compared behaviour among closely related species to come up with hypotheses as to how the behaviour evolved. By comparing the behaviour of closely related species, ethologists could identify homologous behaviours that share a common evolutionary origin and trace the divergence of behaviour over time.
Konrad Lorenz (1903-1989)
Austrian zoologist
Investigated imprinting, famously in greylag geese. Lorenz's work on imprinting demonstrated the importance of early experiences in shaping behaviour and the existence of critical periods for learning.
Lorenz and Imprinting
A goose will imprint on the first moving object it sees. Imprinting is a form of learning that occurs during a critical period in early life, in which young animals form a strong attachment to a particular object or individual.
This is important for recognizing its own species for other behaviours, such as mating. Imprinting helps young animals to identify members of their own species, which is essential for successful social interactions and reproduction.
Karl von Frisch (1886 – 1982)
Austrian zoologist
Bee behaviour, including "waggle dance" Von Frisch's research on bee communication revealed the complex ways in which bees share information about the location of food sources.
Karl von Frisch and the Waggle Dance
Waggle dance shows direction of flowers to other bees. The waggle dance is a ritualized behaviour that bees use to communicate the direction and distance of food sources to other members of their colony.
Niko Tinbergen (1907-1988)
Dutch zoologist
Studied instinct Tinbergen's research on instinctual behaviour helped to clarify the distinction between innate and learned behaviours and to identify the environmental triggers that elicit specific behavioural responses.
Tinbergen's Digger Wasp Experiment
Experiment: Tinbergen marked one nest with a ring of pinecones to test if digger wasps use visual landmarks to locate their nests.
Results: When the wasp returned, she flew to the center of the pinecone circle instead of to the nearby nest.
Conclusion: The experiment supported the hypothesis that digger wasps use landmarks to keep track of their nests. This experiment demonstrated the importance of environmental cues in guiding animal behaviour.
Classical Concepts in Ethology
Fixed action pattern
Chain of reactions
Action-specific energy
Fixed Action Pattern (FAP)
A motor response that may be initiated by some environmental stimulus but can continue to completion without the influence of external stimuli. A fixed action pattern is a stereotyped sequence of movements that is triggered by a specific stimulus and proceeds to completion, even if the stimulus is removed.
Once FAP is started, it continues to completion.
Sign Stimulus or Releaser
Stimulus that triggers FAP. A sign stimulus is a specific environmental cue that triggers a fixed action pattern.
Sign stimulus may only be a small part of any environmental situation. The sign stimulus may be a simple feature of the environment, such as a color, shape, or sound.
e.g., Common toad response to prey
Stickleback Example
When presented with unrealistic models, as long as some red is present, the attack behaviour occurs. The red color acts as a sign stimulus that triggers aggressive behaviour in male sticklebacks.
Chain of Reactions
When one FAP brings the animal into a situation that evokes the next FAP, resulting in a chain of FAPs. A chain of reactions is a sequence of behaviours in which each behaviour serves as a stimulus for the next behaviour in the sequence.
Action Specific Energy
Lorenz 1937
Energy for specific actions is constantly being produced in the animal’s nervous system.
This energy is held back by an inhibitory mechanism until an appropriate stimulus releases it.
The released energy activates certain muscle systems and a particular behaviour pattern results.
Lorenz’s hydraulic model.
Lorenz's Hydraulic Model
The model sees motivation as the result of action-specific energy accumulating in the CNS like fluid in a reservoir.
Behavioural output is determined jointly by the pressure of fluid on a release valve and the pull of an external incentive (weight in the pan) against the valve.
Vacuum and Displacement Activities
The concept of action-specific energy is consistent with two types of behavioural activities:
Vacuum activity
Displacement activity
Vacuum Activity
FAP that is displayed in the absence of stimulus. Vacuum activity occurs when an animal performs a fixed action pattern in the absence of the normal eliciting stimulus.
This behaviour results when action specific energy builds up and cannot be contained.
Vestergaard et al. (1999), re. dustbathing in domestic chicks.
Displacement Activity
During conflict, animals may perform seemingly irrelevant behaviour. Displacement activity occurs when an animal engages in a behaviour that appears out of context during a conflict situation.
When two male gulls meet at the territorial boundary, one may, all of a sudden, start pulling the grass. This behaviour may serve to reduce anxiety or to redirect aggression.
Early to Mid 1900s - Revisited
Ethologists- Europe
Field-based research
Evolutionary questions
Comparative psychologists- America
Laboratory-based research
Mechanism questions
Perceptions Revisited
Ethologists: zoologists interested in a wide range of species and species-typical ways they behaved.
Comparative psychologists: more interested in similarities, seeking general laws in behaviour.
Classical Concepts in Comparative Psychology
Abandon anthropomorphism
Learning and reinforcement
Behaviourism
Abandon Anthropomorphism
Lloyd Morgan
L. Morgan was probably the first to make comparative psychology an objective science.
He argued that behaviour must be explained in the simplest way that is consistent with the evidence and without the assumption that human emotions or mental abilities are involved.
Lloyd Morgan (1852-1936)
Study of animal intelligence.
Not the most rigorous experiments but made important points.
His dog Tony – capable of reasoning??
Threw stick over fence – Tony would retrieve but had to use trial and error over multiple times to get stick back through fence.
Led Morgan to believe that animals learn through trial and error learning.
Morgan's Dog Tony
One day, Tony opened the gate by chance by opening the latch with the back of his head.
Over three weeks, Tony’s performance improved – trial and error.
Reasoning?
Morgan’s canon:
In no case may we interpret an action as the outcome of the exercise of a higher psychical faculty if it can be interpreted as the outcome of one that stands lower in the psychological scale. Morgan's canon is a principle of parsimony that encourages scientists to favor simpler explanations over more complex ones when interpreting animal behaviour.
Learning
Learning is a process in which the animal benefits from experience so that its behaviour is better suited to environmental conditions. Learning allows animals to adapt to changing environments and to improve their chances of survival and reproduction.
Learning abilities are products of natural selection. The capacity for learning has evolved through natural selection, with different species exhibiting different learning abilities depending on their ecological niches and life histories.
Different learning mechanisms among species are suited to their environment.
Types of Learning
Habituation
Classical conditioning
Operant conditioning
Spatial learning
Social learning
Habituation
‘Learning what not to do’
Razran (1971)
Animal learns not to show a characteristic response to a particular stimulus because, during repeated encounters, the stimulus was shown to be harmless. Habituation is a simple form of learning in which an animal decreases its response to a repeated stimulus that is not associated with any positive or negative consequences.
See page 267 Barnard for more…
Benefit of Habituation
It eliminates responses to frequently occurring stimuli that have no bearing on the animal’s welfare without diminishing reactions to significant stimuli. Habituation allows animals to filter out irrelevant information and to focus their attention on stimuli that are more likely to be important for their survival and reproduction.
Classical (Pavlovian) Conditioning
A stimulus that initially does not elicit a response comes to do so by association with a stimulus that does. Classical conditioning is a form of learning in which an animal learns to associate a neutral stimulus with a stimulus that elicits a response, such that the neutral stimulus eventually elicits the same response.
Pavlovian or Classical Conditioning
Unconditioned stimulus (UCS): Meat
Unconditioned response (UCR): Salivation
Conditioned stimulus (CS): Bell/Clicker/etc.
Conditioned response (CR): Salivation
Operant Conditioning
When a behaviour has favourable consequences, the probability that the act will be repeated is increased. Operant conditioning is a form of learning in which an animal learns to associate its behaviour with a particular consequence, such that behaviours that lead to positive consequences are more likely to be repeated.
Operant conditioning = animal operates on the environment to produce consequences.
Reinforcer: stimulus that alters the probability of a behaviour being repeated
Positive reinforcer: A stimulus that increases the probability of a behaviour being repeated when it is presented after the behaviour.
Negative reinforcer: A stimulus that increases the probability of a behaviour being repeated when it is removed after the behaviour.
Spatial Learning
Training conditions involved pine cones near a nest in sand. Spatial learning is a form of learning in which an animal learns to navigate and remember the locations of important resources in its environment.
Social Learning
Some organisms can learn from others. Social learning is a form of learning in which an animal learns by observing the behaviour of others.
Behaviourism
Offshoot of comparative psychology that rejected any explanation of behaviour that depended upon unobservable causes. Behaviourism is a school of thought in psychology that emphasizes the importance of observable behaviour and rejects the study of mental processes that cannot be directly observed.
Behaviourism - Details
Offshoot of comparative psychology.
Behaviourists designed experiments that would yield quantitative data.
Invented apparatus to measure and record responses.
Assumption: an animal’s mental capacity could not be measured directly, but its ability to solve problems could.
Watson, J.B. (1913) Psychology as the behaviorist views it. Psychological Review, 20, 158-177.
History of Animal Behaviour - Revisited
The beginnings with Darwin
Classical Ethology
Comparative psychology
Nature versus Nurture controversy
Sociobiology/Behavioural ecology
The Nature Versus Nurture Controversy
Differences in beliefs about the importance of inheritance or experience in behaviour caused a rift between European ethologists and American comparative psychologists. The nature versus nurture debate is a long-standing controversy about the relative importance of genetic inheritance (nature) and environmental experience (nurture) in shaping behaviour.
Ethologists believed that the behaviour primarily is inherited.
Comparative psychologists believed that the behaviour is modified with experience.
Resolution of the Nature vs. Nurture Debate
There was a controversy whether the behaviour is primarily learned or instinctive.
This controversy raged for about 20 years.
The current wisdom is that there is an intimate relationship between the learned and genetic (instinct) contributions to behaviour. Most modern researchers recognize that both genetic and environmental factors play important roles in shaping behaviour and that the two are often intertwined.
Sociobiology and Behavioural Ecology
After the reconciliation between the ethologists and comparative psychologists, a new field in animal behaviour emerged called sociobiology. Sociobiology is a field of biology that studies the evolutionary basis of social behaviour.
It tended to apply evolutionary theory to social behaviour, referred to as sociobiology after E.O. Wilson’s seminal book.
Cornerstones of Behavioural Ecology
William Hamilton’s notion of inclusive fitness. Inclusive fitness is a measure of an individual's reproductive success, taking into account the reproductive success of its relatives.
Evolutionary Stable Strategies (ESS) - adaptive decision-making is frequency dependent. An evolutionarily stable strategy is a strategy that, if adopted by a population, cannot be invaded by any alternative strategy.
Optimality theory recognizes both costs and benefits and suggests that traits have evolved to be optimal – the best they can be under existing conditions. Optimality theory assumes that natural selection favors traits that maximize the difference between the benefits and costs to an animal.
Key Points
Why animal behaviour is studied.
What are the research questions in animal behaviour.
History of animal behaviour.
Classical concepts in ethology and comparative psychology.
Suggested Books
Alcock, J. 1998 (or later edition). *Animal behaviour