In-depth Notes on Animal Behaviour

Module IV ~ Video 1 ~ Animal Behaviour

  • Framework for Understanding Behavioural Diversity

    • Develop a structured approach to studying behaviours in animals and plants.

    • Focus on understanding the complexity of behaviours beyond simple technical definitions.

  • Definition of Behaviour

    • Behaviour is defined as an action executed by muscles under the control of the central nervous system in response to a stimulus.

    • The study of animal behaviour combines physiological and biochemical processes.

    • Understanding evolution of behaviour is complicated by interactions within and between species.

Niko Tinbergen's Four Questions

  • Questions for Understanding Behaviour

    • What stimulus and physiological mechanisms are involved?

    • How does experience influence behaviour?

    • How does behaviour affect survival and reproduction?

    • What is the evolutionary history of a behaviour?

    • Tinbergen's framework provides a concise model for exploring behaviour.

Simple vs. Complex Behaviours

  • Fixed Action Patterns

    • Simple behaviours elicited by specific stimuli.

    • Example: Male three-spined sticklebacks display aggression towards red objects (even non-live forms) during territory defence and courtship.

    • Tinbergen's experiments established the role of the colour red in eliciting behaviours.

  • Complex Behaviours

    • Involves learning and adaptation to environmental factors.

    • Migration as an elaborate behaviour pattern influenced by various environmental cues (e.g., circadian rhythms).

Migration Patterns

  • Seasonal Migration

    • Examples: Snow geese migrate from the Arctic to the Gulf Coast for winter.

    • Monarch Butterflies migrate from Mexico with generational changes in their route.

    • Environmental stimuli and internal biological rhythms govern migration schedules.

  • Navigational Cues

    • Use of celestial bodies (sun and stars) and Earth's magnetic field.

  • Diel Vertical Migration

    • Many oceanic organisms migrate daily for feeding and safety from predators during the night.

Modes of Communication

  • Signaller-Signal-Medium-Recipient Model

    • Communication can be of various forms, especially during courtship.

    • Example: Fruit flies utilize visual, olfactory, tactile, and auditory means for courtship.

    • Important for species adaptation to environments influencing communication effectiveness.

  • Pheromonal Communication

    • Many insects and mammals use pheromones for chemical communication.

    • Example: Gypsy moths use pheromones for mate attraction, which can be manipulated to control populations.

Impact of Human Activity on Behaviour

  • Disruption of Natural Communication

    • Water pollution affecting cichlid mating behaviours due to altered visual cues.

    • Anthropogenic noise impacting sound communication among birds.

Learning and Behaviour

  • Types of Learning

    • Imprinting: Learning that occurs at a specific life stage, influencing future behaviours persistently.

    • Example: Young birds imprint on species-specific characteristics for future mate selection.

  • Spatial Learning

    • Evidence of cognitive abilities observed through experiments in wasps and honeybees, revealing adaptability in foraging.

  • Associative Learning

    • Ability to link stimuli or experiences with specific outcomes.

    • Example: Blue jays learning to avoid poisonous monarch butterflies after negative experiences.

Behaviour Under Natural Selection

  • Foraging Behaviour

    • Balancing energy gain and risks while foraging.

    • Optimality models can predict foraging decisions based on patch quality and distance.

  • Risk-sensitive Foraging

    • Foragers adjust their strategies based on the risk of predation and hunger levels; demonstrated in experiments with food patches.

  • Sexual Selection

    • Involves intrasexual competition (e.g., males competing for territory) and intersexual mate selection (e.g., females choosing mates).

Alternative Mating Strategies

  • Mating Behaviour Variations

    • Sneaker strategies and alternative morphs, such as in bluegill sunfish, promote genetic diversity and reproductive success.

Parental Care

  • Conflict Between Parent and Offspring

    • Parents must balance investment according to fitness benefits while offspring seek maximum care leading to conflict dynamics.

Plant Behaviour

  • Understanding Plant Behaviour

    • Herbivores and pollinators interact within a complex communication framework influenced by environmental conditions.

  1. What is the definition of behaviour in animals?

  2. Describe Niko Tinbergen's Four Questions used for understanding behaviour.

  3. Explain the difference between fixed action patterns and complex behaviours.

  4. What are the navigational cues used by migratory animals?

  5. How do environmental stimuli and biological rhythms influence seasonal migration?

  6. Describe the Signaller-Signal-Medium-Recipient model in communication.

  7. What impact does human activity have on natural communication among animals?

  8. Describe the different types of learning observed in animal behaviour.

  9. How does natural selection affect foraging behaviour?

  10. Discuss the concept of parental care and conflicts between parents and offspring.

  11. Explain how plant behaviours can be influenced by interactions with herbivores and pollinators.