BIO SCI 94 Chapter Notes - Chapter 51: Pair Bond, Serenade, Animal Communication
Course CodeBIO SCI 94
ProfessorNancy Aguilar- Roca
Biology Notes Chapter 51 Animal Behavior
Saturday, March 1, 2014
Animal Behavior - action carried out by muscle under control of the nervous system in response
to a stimulus.
In other words , its how an animal is designed to reaction to a situation.
Ex: a dog peeing to mark its territory
Behavior allows an organism to survive. Certain behaviors allow an animal to have an
advantage over others , thus natural selection "picks " certain behavior over others.
This evolution also effects the anatomy of animals . So if having a big threat allows an organism
to make a bigger / deeper noise to attract mates, then a species in general may have bigger
Concept 51.1 - Discrete Sensory Inputs can Stimulate Both Simple and Complex Behaviors
How to understand a behavior in 4 steps (Niko Tinbergen)
1. What stimulus starts/ causes/ triggers the behavior?how can the response be
physically carried out?
2. How does the animal's experience during growth and development influence the
3. How does this behavior help the animal survive and reproduce
4. What is the behavior's evolutionary history.
1 & 2 concern proximate causation - the how a behavior occurs.
3&4 concern Ultimate Causation- the "why" a behavior occurs ( natural selection)
Behavioral Ecology - study of ecological and evolutionary Basis for animal behavior
Fixed Action Patterns
Ex: male sticklebacks attacking any object or model with red color
Fixed action pattern: a sequence of unlearned acts directly linked to a simple
typically unchangeable , once this action is started it's finished
Sign Stimulus - Trigger for the behavior ( in the case of the stickleback fish , it’s the
color red apparently)
Environmental Stimuli also give cues for animals to carry out behaviors, like guiding
Migration - regular , long distance change in location.
How is this done ?
Some track position based on the sun , even though that changes throughout the day
They adjust for these changes by means of Circadian Clock - internal guide that has a
24 hour cycle.
other animals use the Earth's Magnetic Field
Circadian rhythm plays huge role in everyday activities of all animals
"clock" is synched with light and dark of day usually
Longer periods than a day are circannual rhythms
Both " clocks are influenced by light/ dark of day , moon cycles etc
Animal Signals + Communication
Signal- Stimulus transmitted from one animal to another (ie sound)
Communication- transmission and reception of signals ( ie talking)
Forms of animal communication
Visual -Male Fly is all " ooo it’s a female fly"
Chemical - Female fly releases chemical so the male can smell her
Tactile , touch - Male fly taps her abdomen - " hey, whats cookin' good lookin"
Auditory- Male pulls out a wing and proceeds to serenade the female :) :) :)
Stimulus response chain - the response of a stimulus becomes the stimulus of the
next behavior. Ie the female fly's response to the male's appearance becomes the
trigger ( stimulus) for the male fly to tap her belly
Chemical substance that is for Communication via odor/ taste
Common with reproductive behavior
Also are alarm signals, so when a fish gets scared it will release chemicals in the water and the
other fish will react accordingly
Selection for individual Survival and reproductive success can explain most behaviors.
Natural selection refines behaviors that help animals get food
Foraging- is eating and activities animals use to search for and recognize + capture food
Evolution of foraging behavior
Gene (for) dictates the how a fly larvae looks for food
Maggot with forr allele travels 2x as far when feeding than larvae with frs allele
Enzyme for forager locus is more active in forr larvae than fors
Gene frequency depends on circumstance
Optimal foraging model
Natural selection choses foraging behavior that is cost effective for organism
Maximum energy gain, minimal energy costs
Mating Behavior and Mate Choice
Most mating is promiscuous; no strong pair bond
Monogamous- one male and one female
Polygamous, one individual with several other
Mating systems and parental care
Male that stays to protect young has more viable offs spring
Thus birds are monogamous