AP Bio
Chapter 51 Notes
Behavioral Ecology studies how behavior is controlled and how
it develops, evolves, and contributes to the survival and
reproductive success of a species. Behavioral ecology is
essential to solving critically important problems ranging from
conservation of endangered species to the control of emerging
infectious diseases.
Behavior is everything an animal does and how it does it,
including muscular and non-muscular activity. Learning is also a
behavioral process.
Distinguishing between proximal and ultimate causes of
behavior: proximal questions ( “how” questions) focus on the
environmental stimuli, if any, that trigger a behavior, as well as
genetic, physiological, and anatomical mechanisms underlying
the behavior. Ultimate questions (“why” questions) address
the evolutionary significance of a behavior. (Why did natural
selection favor this behavior and not a different one?)
Ethology: is the scientific study of animal behavior, particularly
in natural environments. In the mid-20th century, scientists
developed a set of 4 questions that must be answered to fully
understand any behavior.
1. What are the mechanisms of the behavior, including
chemical, anatomical, and physiological mechanisms?
2. How does development of animal, from zygote to mature
individual, influence behavior?
3. What is evolutionary history of the behavior?
4. How does the behavior contribute to survival and
reproduction (fitness).
This list includes proximal and ultimate questions. 2 behaviors
frequently studied are FAP (fixed action patterns), and
imprinting. FAP’s are unlearned behaviors that are essentially
unchangeable and once initiated will continue till completion
(Ex. stickle back fish). Imprinting is a behavior that includes
both innate and learned components and is generally
irreversible. (ex: geese, ducks, cranes)
Many behaviors have a strong genetic influence:
Biologists study the ways both genes and the environment
influence that development of behavioral phenotypes.
Behaviors that are “developmentally fixed” are called innate
behaviors.
Directed movements:
Kinesis: is a simple change in activity or turning rate in response
to a stimulus. Taxis: is a more or less automatic, oriented
movement toward or way from a stimulus. Experiments have
demonstrated that bird migration is at least partially under
genetic control.
Animal signals and communication:
The transmission of, reception of and response to signals
constitutes animal communication. Animals communicate
using visual, auditory, chemical, tactile and electrical signals.
Genetic influence on mating and parental behavior:
A variety of mammalian behaviors are under relatively strong
genetic control. Ex. research of prairie voles show strong
genetic and neural basis for mating and parenting behaviors
Environment, interacting with an animal’s genetic makeup,
influences the development of behaviors
Environmental factors such as diet, the nature of social
interactions and opportunities for learning can influence the
development of behaviors in every group of animals.
Ex. Dietary influence on mate choice behaviors; the type of
food eaten during larval stage development can influence later
mate selection of Drosophila mojavensis (lay their eggs on
rotting catus)
Learning:
Is a modification of behavior based on specific experiences
Types of learning includes habituation, spatial learning, use of
cognitive maps, and associative learning.
Habituation: a loss of responsiveness to stimuli that contain
little or no information
Spatial learning: is the modification of behavior base on
experience with the spatial structure of the environment,
including the locations of nest sites, hazards, food, prospective
mates.
Cognitive maps: an internal representation, or code, of the
spatial relationships between objects is an animal’s
surroundings.
Associative learning: the ability of many animals to associate
one feature of the environment with another. (color to bad
taste). Operant conditioning: trial and error learning. An animal
learns to associate one of its behaviors with a reward or
punishment. (Pavlov’s dog experiment)
Cognition and problem solving:
Cognitive ethology: the study of the connection between an
animal’s nervous system and its behavior. Ex. watching an
animal solving a problem
Behavioral traits can evolve through natural selection
When behavioral variation within a species corresponds to
variation in the environmental conditions, it may be evidence
of past evolution.
Natural selection favors behaviors that increase survival and
reproductive success:
Foraging behaviors: animal behaviors including eating, and
methods for searching, recognizing, and capturing food items.
Optimal foraging theory: foraging behaviors that utilizes
compromise between the benefits of nutrition and the cost of
obtaining food, such as energy expenditure or risk of being
eaten by a predator.
Mating behavior and mate choice: includes seeking or
attracting a mate, choosing among potential mates, and
competing for mates.
Promiscuous; no strong pairing bonds or last relationships.
Monogamous: mates remaining together for a longer period,
one male to one female.
Polygamous: lasting relationships usually with one male to
many females.
Polyandry: one female with several males
Applying game theory: evaluates alternative strategies in
situations where the outcome depends not only on each
individual’s strategy but also on the strategies of other
individuals. Is a way of thinking about evolution in situations
where the fitness of a particular behavioral phenotype is
influenced by other behavioral phenotypes in the population.
Game theory gives biologists a way to think about complex
evolutionary problems in which relative performance, not
absolute performance, is the key to understanding the
evolution of behavior.
Altruism: on occasion animals behave in altruistic ways to
reduce their individual fitness but increase the fitness of the
recipient of the behavior.
Inclusive fitness: the total effect an individual has on
proliferating its genes by producing its own offspring and by
providing aid that enables close relatives to produce offspring.
Kin selection, favors altruistic behavior by enhancing the
reproductive success of relatives. Altruistic behavior toward
unrelated individuals can be adaptive if the aided individual
returns the favor in the future – reciprocal altruism.
Social Learning: forms the roots of culture, which can be
defined as a system of information transfer through
observation or teaching that influences the behavior of
individuals in a population.
Evolution and Human Culture: Human behavior , like that of
other species, is the result of interactions between genes and
environment. However, our social and cultural institutions may
provide the only feature in which there is no continuum
between humans and other species.