Behaviour
Behavioural Biology
Behaviour
Definition: What an animal does
Reference: [Link](http://www.duiops.net/seres vivos)
Behavioral Ecology
Definition: WHAT organisms do and WHY they do it
Key Concepts:
Ecology
Evolution
Behavior
Studying Behavioral Ecology
Types of Questions:
Proximate Cause:
Definition: Examines the immediate cause/mechanism of a behavior.
Example: Increased day length causes pineal gland to trigger hormones that trigger reproductive behavior.
Ultimate Cause:
Definition: The evolutionary reason for a behavior (WHY).
Example: Individuals breeding in spring were more successful due to factors like food availability and temperature.
Examples of Behaviors:
Animals startled by loud noises:
Proximate cause: Loud noise induces an automatic reflex response.
Ultimate cause: Moving quickly from loud noises may limit the risk of mortality.
Bats breeding in early spring:
Proximate and ultimate causes not specified, but relate to seasonal changes and survival advantage.
Evolution of Behavior
Approach:
Study the evolution of behavior in the same way as any trait.
Natural Selection as an Explanation for Evolution:
Variability in the trait
Trait must be heritable
Trait must cause differential reproductive success.
A Brief History
Proverbs 6:6: "Go to the ant, O sluggard, and consider her ways and be wise".
Notable Figures in Ethology:
Niko Tinbergen
Konrad Lorenz
Karl von Frisch
Nobel Prize: 1973 for Physiology & Medicine.
Ethology
Definition: Study of the natural history of behavior.
Key Concept:
Innate Behavior:
Characterized by instinctive actions requiring no prior learning.
Follows preset paths in the nervous system and is often genetically fixed.
Fixed Action Pattern:
Example: Goose behavior of replacing an egg from her nest.
Sign Stimulus: Triggers a fixed action pattern through external sensory stimuli.
Niko Tindbergen's Discoveries
Example: Male sticklebacks are territorial and respond primarily to the red color patch, not the shape, of other males and objects.
Fixed Action Patterns: Innate, stereotyped behaviors triggered by specific stimuli.
Innate Behavior
Egg Retrieval Behavior: Triggered by a key or sign stimulus.
Example: An egg that is out of the nest.
Innate Releasing Mechanism:
Perception of a key stimulus leads to the triggering of a motor program (fixed action pattern).
Once the pattern begins, it continues to completion even if the egg is removed (similar to yawning).
Imprinting
Definition: An innate response to a specific stimulus.
Critical Period: A limited time during which imprinting can occur.
Example: Greylag goslings raised with their mother exhibit normal behavior; those hatching with Konrad Lorenz imprint on humans instead.
Honey Bees Communication
Research by Von Frisch reveals honey bees use complex behaviors resembling language to direct foragers to food sources using internal clocks and polarized light detection.
Behavioral Genetics
Concepts:
Nature vs. Nurture:
Genes influence the development of the nervous system and potential behavioral responses.
Social environments and experiences also guide behavior development.
Introduction to hereditary contributions to behavior.
Effects of Genetics on Behavior
Behavioral differences among individuals can stem from genetic variations.
Artificial Selection:
Example: Selecting for behaviors in animals based on genetic traits.
Case Study: Fast vs. Slow Rats
Parental Generation:
Fast rat population: Errors in maze negotiations
Total Errors: 9, 39, 64, 114 (Fourteen Trials)
Slow rat population: Similar data.
Results show trends through generations indicating behavioral genetics in action.
fosB Gene in Mice
Importance of the fosB gene:
Determines if female mice will nurture their young.
Disabled fosB alleles lead to a lack of maternal behavior; normal mothers exhibit protective behavior.
Mechanism involves activation of proteins affecting neural circuits in the hypothalamus.
Selection for Responses to Hormones
Prairie Voles vs. Montane Voles
Prairie Voles:
Characteristics: Monogamous, mate for life, provide biparental care.
Montane Voles:
Characteristics: Promiscuous, polygynous, maternal care only.
Differences linked to brain structure and hormone receptors.
Vasopressin and Pair-bonding Behavior
Prairie voles have more vasopressin receptors in the brain, influencing their social bonding behavior.
Comparative studies with wild-type mice and transgenic mice with prairie vole gene show a significant difference in pair bonding when exposed to vasopressin.
Example of Natural Selection
Fischer's Lovebirds:
Known for a specific nesting behavior:
Carrying nest material in their beaks (peach-faced lovebirds) vs. tails (Fischer's lovebirds).
Hybrid lovebirds exhibit mixed behaviors with less effectiveness.
Questions in Behavioral Biology
Why are species sexually dimorphic?
Why do some species exhibit bright coloration?
Reasons behind social structures where only a few individuals reproduce.
Existence of extreme size differences within species.
Evolution of mimicry and camouflage.
Parental care behavior towards offspring.
Research on Alarm Calls
Similar structures in alarm calls across different species raise questions about communication and evolutionary advantages.
Female Zebra Finches' Preferences
Investigation into why female zebra finches are drawn to males with unique head feathers.
Learning and Animal Behavior
Fundamentals of Learning:
Basis for much of animal behavior; changes due to earlier experiences.
Nonassociative Learning:
Characterized by no association between two stimuli or a stimulus and response.
Examples:
Habituation: Decrease in response to a repeated stimulus with no consequences for behavior.
Associative Learning
Definition: Learning that results from pairing two stimuli.
Types:
Classical Conditioning:
Formation of associations between two stimuli.
Example: Dog salivation response to food and bell ringing.
Operant Conditioning:
Association of behavior with rewards or punishments.
Classical Conditioning Example
Typical Scenario:
Unconditioned response: Dog salivates at the sight of food.
Conditioning: Bell rings every time food is presented.
Conditioned response: Dog salivates to bell alone after conditioning.
Operant Conditioning
Definition: Animals learn behaviors through association with rewards or punishments.
Example: B.F. Skinner's experiments with rats in the Skinner box.
Rats learn to press levers for food rewards; results indicate learned responses can occur faster under punishment conditions.
Learning & Animal Behavior: Case Study
Blue Jays and Monarch Butterflies:
Naive blue jay eats a monarch and gets sick, avoiding orange and black butterflies in future encounters.
Animal Cognition
Inquiry into Cognitive Behaviors:
Do animals display behaviors indicative of cognitive processing?
Examples:
Chimpanzees show problem-solving skills to access food.
Japanese macaques learned to wash potatoes.
Social Systems and Advantages
Definitions and Concepts:
Society: A cooperative group of organisms of the same species.
Advantages include protection from predators and improved feeding success.
Flocking Behavior
Data suggest flocking behavior significantly decreases predation success rates.
Measurements include various types of reactions to predation based on flock size.
Diverse Insect Societies
Characteristics:
Specialized individuals by task:
Examples:
Honeybees with distinct roles and caste systems.
Leaf-cutter ants with differentiated tasks.
Vertebrate Social Structures
Typically less rigid than insect societies; influenced by diet and predation strategies.
Example: Meerkat with sentinel duties; Naked mole rats demonstrating a reproductive division of labor with a single queen.
Conclusion
Behavioral biology is an expansive field encompassing the study of animal behaviors through various lenses, including ecology, genetics, and social dynamics. Its exploration provides deeper insights into the mechanisms driving behavior and evolutionary advantages. Understanding these fundamental concepts allows us to appreciate the intricate relationships between an organism's behavior, its environment, and evolutionary history.