Animal Behavior pt9-10

piloting

the ability of an animal to find its way using landmarks.

Landmarks can be visual, olfactory & magnetic magnetic

Compass Orientation

ability of an animal to find its way without using landmarks. keeps a certain angle towards an external reference system

ex: stars, magnetic fields, sun

vector navigation

inherited program telling an animal the compass direction to head in and for how long to travel

path integration

process by which an animal integrates information on the sequence of direction and duration of each leg of an outward journey and uses that information to return

true navigation

animal’s ability to maintain or establish reference to a goal, regardless of its location, without the use of landmarks.

• will not get lost if displaced by a researcher

“homing”

landmarks

easily recognizable cue that can be stored quickly in an animal’s memory to guide it on a later journey

"sextant and chronometer"

a built-in ability to read patterns of stars and to navigate by them, which also requires an accurate time-of-day clock.

Angle of Inclination

angle that the line of force makes on the horizon. inclination compass allows an animal to determine if it is going toward the pole or toward the equator.

• poleward

• equatorward

poleward

lines of force are the steepest

equatorward

lines of force are parallel to the earth’s surface

Magnetoceptor for birds

Magnetite (Fe₃O₄)

magnetic map

allows an animal to obtain positional information from the earth’s magnetic field. may be learned or inherited depending on the species.

magnetic signposts

innate ability to respond to magnetic landmarks that will trigger a directional change

Magnetoception

sense which allows an animal to detect a magnetic field to allow it to perceive direction, altitude or location

Cryptochrome

allows for detection of magnetic fields.

• activated when exposed to blue light.

• Activation may affect the light-sensitivity of retinal neurons, with the overall result that the animal can "see" the magnetic field

Papi’s “Mosaic” Model

advocates that animals construct a map from the distribution of environmental odors

• as a limited area of affect

• homing using odors is viable only if the animal is located within a proximity that can provide olfactory cues

Wallraff’s “gradient” Model

proposes the existence of long-range, stable atmospheric odor gradient

Natal Philopatry

when offspring remain within their birth area throughout their lives.

Costs of Natal philopatry

1. increased competition

2. inbreeding

3. mating suppression

What determines the gender that leaves the population?

1. inbreeding

2. mate competition

3. kin cooperation

Three phases of habitat selection?

1. search

2. settlement

3. residency

public information

presence of conspecifics in a potential habitat is that it informs the animal that the resources it needs are present

Comparison Tactic

involves visiting several areas, revisiting some of the more eligible ones, and then choosing the area determined to be of the highest quality.

• might come back

Sequential Search Tactic

involves visiting an area, evaluating whether to reject of accept it, and moving on if it is rejected

• never comes back

Natal Habitat Preference Induction

will try to find habitat that is similar to the one they grew up in

Two Way migration

leaving an area and then later returning to it.

• generally in long living species

One Way migration

leaving the home range for a new location and never returning to the original home range.

ex: pacific salmon

Obligate Migration

all animals in species must migrate

ex: wildebeast migration

Facultative Migration

migration where individuals can choose to migrate or not.

• on species level

ex: only sexually mature pacific salmon migrate to breed

complete migration

all individuals in population migrate

partial migration

some individuals in pop. migrate

• Differential Migration

Differential Migration:

difference between migratory and non-migratory individuals is based on factors such as age or sex

multigenerational migration

migration takes more than one generation to complete

• more common in short lived species

ex: monarch butterflies

Daily migration

occur on regular basis inn 24hr period

• vertical migration

Irruptions

displacement of animals due to pressure of famine, overpopulation, or other obscure influences

Migration Costs of fitness

1. require large amounts of energy

2. exposes animal to predation

3. adverse effects b/c of shifts in weather

4. crossing inhospitable terrains and obstacles

Migration Benefits to fitness

1. increase in resources

2. reproductive benefits

3. reduce predation

4. reduce interspecific competition