Animal Behavior Exam 3

Orientation

Coordinated movement that occurs in response to external stimuli.

Adaptive value of orientation

Avoid predators, find food, and mate.

Categories of orientation

short distance, long distance, and dispersal.

Short-distance orientation

Distance is short enough that the animal can sense the stimulus; taxis and kinesis; one-way trip.

Long-distance orientation

Distance is too long to detect the stimulus; migration; two-way trip (there and back).

Dispersal

One-way trip from natal site (place where born).

Arctic tern

travels 244,000 miles from the Arctic to Antarctica.

Taxis

Movement directly toward (positive) or away (negative) from a stimulus.

Kinesis

increase in random movement, lasts until a favorable environment is reached

Taxis vs. kinesis classification

Not categorized by stimulus type, but by type of movement.

Stimuli

Light, chemicals (pheromones), magnetic field, humidity, sound, wetness.

Taxis and innate behavior

Type of stimulus is not important in terms of behavior; behaviors are innate.

Positive phototaxis (kinesis)

Movement toward a light stimulus.

Negative phototaxis (kinesis)

Movement away from a light stimulus.

Cockroach response to light

negative phototaxis (kinesis) they do no like light

Types of taxis

Klinotaxis and tropotaxis

Klinotaxis

Side-to-side motion of head or body with successive comparison of stimulus intensity

Organisms using klinotaxis

Small organisms

Sensory receptors in klinotaxis

One sensory receptor or two sensory receptors that are very close to each other.

Euglena klinotaxis example

Moves toward dim light or away from bright light. One stimulus detected by eyespot; sways side to side in a zigzag pattern.

Human scent example

Humans like the scent of food and sniff to locate it.

Male moth orientation example

Male follows female using chemical stimuli with the same swaying movement.

Tropotaxis

Stimulus is sensed by paired (two) sensory receptors that are far enough apart to allow movement in a straight line toward or away from the stimulus.

Tropotaxis example human

Humans hearing a bell and moving directly toward the sound.

Tropotaxis example snake

snakes have a forked tongue with distance between sensory receptors.

Types of taxis by stimulus

Phototaxis, chemotaxis, etc.

Kinesis

Random walk.

Types of kinesis

Change in speed of movement and change in rate of turning; both are directly proportional to stimulus intensity.

Klinokinesis

Turning movements that change the rate of turning.

Klinokinesis in preferred conditions

Animals prefer the condition and increase turning rate.

Cockroach kinesis example

No direct movement; random movement or walks. Turning rate increases with darkness, not with light.

Dracula lacteum (planaria)

Spins and prefers darkness.

Lice habitat preference

Prefer darkness and cool areas; do not prefer heat and light.

Soil nematodes feeding behavior

Circle around food

Orthokinesis

Speed of movement is related to intensity of stimulus.

Wood louse / pill bug habitat example

Found under rocks, logs, and leaves. Prefer moist, warm areas. Low humidity is dry; high humidity is moist. Movement in preferred conditions: Little distance covered per unit time; slow movement with many turns.

Cricket phonotaxis

Males hear female calls and follow them.

Karl von Frisch

Studied bees.

Bee communication (signal)

Occurs when a sender produces a signal that contains information.Signal is transmitted through the environment, detected by the receiver, interpreted, and responded to.

Honey bee menotaxis

Directional movement using contrast angles relative to a source.

Honey bee foraging timing

Sugar bowls checked by foragers in the morning at sunrise.

Hive orientation

Occurs inside the hive.

Foragers dance to communicate the location and type of food. Opening of the hive faced the sun in the east.

Round dance

Big circular back-and-forth movement. Food source is less than 50 meters away. Repeated several times; forager gives samples to other bees for taste; gives distance but no location.No specific location given; only east.

Waggle dance

Dance with NESW direction and an angle.Food source is greater than 150 meters away. Communicates angle and distance; used when food is too far away; every second equals 1 km.

Honey bee dance communication experiments (Karl von Frisch)

Bees communicate food location inside the hive using dances. In experiments, hives were placed with food straight east of the opening; 19 bees found the food and 17 returned and performed the round dance. Food was later placed 10 meters up on a pole; bees did not change the angle, and a 2005 experiment proved von Frisch was correct. Unmarked foragers moved southwest still went 200 miles east. Bees communicate socially.

2025 bee prob solving experiment

Tested whether bees can solve problems. Bees were trained to taste sugar water. A tail was attached so bees had to pull it.

Long-distance movement (migration)

Movement with costs and benefits that occurs between hemispheres and regions with seasonal differences in food and predators.

Pre-migration costs

Energy use, pre-migration foraging with predators present, and high winds.

Pre-migration benefits

Access to food, differences in predators, and seasonal advantages between Northern and Southern Hemispheres.

Migration costs

Different predators, strong wind currents (especially over water), traveling alone or in flocks (11–14 help in updraft beat), crashing into buildings, buildup, planes, cars, getting lost, and wind.

Proximate cues for migration

Photoperiod (sunlight); temperature is not reliable.

Migration near the equator

Photoperiod is not accurate, so animals rely on quality and quantity of food resources.

Serengeti migration example

Wildebeest migration based on quantity and quality of food; biomass of grass for nutrition; no winter/summer but dry and wet seasons.

Serengeti dry season

January to October; decreased rainfall and sunny days; grass grows slower and has decreased nutritional value.

Migration timing in birds

Birds migrate at night; zugunruhe begins around April.

Zugunruhe

Restlessness indicating readiness to migrate, shown as two bounds of activity.

Emlen funnel

Experimental tool used to study migratory orientation.

Indigo bunting migration (Emlen experiments)

Birds showed pre-migration ink marks in funnels oriented southwest toward Central America using stars; lab birds showed the same behavior; in March they migrated to the U.S.; spring migration from South America back northeast.

Star navigation

Birds migrate using stars; Polaris (North Star) is close to the north celestial pole and moves very little.

Planetarium star manipulation experiment

Betelgeuse (southwest of Polaris) was made stable while Polaris was moved; birds oriented toward Betelgeuse.

Examples of bird migration routes

European starling migrates in flocks; Arctic tern migrates over ocean; ruby-throated hummingbird migrates to Guatemala.

True navigation

Knowing how to find home no matter location or compass direction; accurately determining and moving in the correct direction.

Indigo bunting and navigation

Birds know to go southwest and then northeast; birds orient but do not show true navigation.

European starling displacement experiment

Conducted in the 1940–50s by Arthur Reredeck; 14,000 birds captured (fledglings and adults) from the Netherlands and displaced to Switzerland. Fledglings went to Spain or North Africa; adults went to France and some fledglings followed; experiment was messy and showed most birds are not true navigators.

Pigeons and navigation

Pigeons have true navigation and know where they are; some use sun, stars, and magnetic cues (water).

Dispersal

One-way trip from the natal site (place where born).

Sex-biased dispersal

In some species, males or females disperse more than the other sex.

Ecologist perspective on dispersal

Focuses on the number of animals that disperse and the movement into and out of a population that affects population growth and gene flow.

Behaviorist / ethologist perspective on dispersal

Focuses on what causes an animal to disperse and why they leave.

Behavioral questions about dispersal

Asks whether dispersal is linked to age, sex, or behavioral history, and whether behavioral syndromes make some individuals more likely to disperse than others.

Who disperses

Adolescents or young individuals.

Natal dispersal

Dispersal that occurs when individuals leave their birthplace.

Reason for natal dispersal

Young individuals lack experience and strength, cannot take over favored locations from parents, or are driven out of parental territory.

Sex differences in dispersal

Males leave in most mammals; females leave in most birds.

Mammal male-biased dispersal

Common in polygamous systems with one dominant male controlling territory and multiple females.

Polygamous mammal social structure

One dominant male controls land with many females and defends it against other males and sons.

Reasons young males disperse in mammals

Must find territory, avoid inbreeding, and avoid family competition.

Visibility and dispersal in mammals

Males are large, active during the day, and easily seen.

Wild horse dispersal

Young males (1–5 years old) form groups and are kicked out.

Bachelor herds

Groups of displaced males that are not strong enough to control territories or females.

Mature male horses

Males aged 27 years or older that can control territories and females.

Female dispersal in mammals

Females generally do not leave.

Why female mammals do not disperse

Females are suitable for mating, and males with territory will accept them into their harem.

Female-biased dispersal in birds

Females disperse more than males. Birds are on average monogamous or serially monogamous; females need to find males, so they leave.

Male role in bird dispersal

Males defend resources and females and therefore do not leave.

Benefits of dispersal

Access to mates, avoidance of inbreeding, reduced resource competition, better sites, increased reproductive success.

Costs of dispersal

Increased predation risk, poorer habitat, and good sites already being taken.

Gunnison prairie dogs dispersal

Females continue dispersing because females become pregnant and must leave.

Red-backed salamander dispersal

Males disperse more than females.

Egyptian vulture dispersal

Females disperse.

Competition dispersal

Dispersal caused by competition related to density and food availability.

Competition dispersal experiment variables

Manipulated diversity of individuals and amount of food.

Density-based dispersal result

When food amount is the same but density differs, individuals leave high-density sites.

Springtail (Hexapoda)

Small wingless organism (~6 mm), six legs, lives in moist environments, jumps using a furcula, always lands on its feet.

Springtail density experiment

Group A had 30 individuals; Group B had 900 individuals; dispersal occurred from high-density groups.

Food-based dispersal result

When density is the same but food differs, individuals leave low-food sites.

Bird dispersal timing

Birds disperse after birth when competition with kin is high.

Nothern Goshawk

Hatch in April; independent by August (~80 days). Lives in forests; breeding pairs defend territories ~2 km; produce 1–2 offspring per year.

Goshawk experiment

28 broods total; radio transmitters placed on chicks at day 21; EX group received dead Japanese quail every other day; control received no extra food. Control offspring dispersed earlier and farther (~25 km); EX offspring stayed closer due to higher perceived food density.

Inbreeding avoidance

Dispersal reduces mating with close relatives.