Ecology Exam 3

when an individual that has a social bond with a mate also breeds with other individuals.​

a behavior in which one partner prevents the other partner from participating in extra-pair copulations

Differential survival and reproduction due to sex-specific traits that are related to reproduction; leads to a variety of differences between males and females.​

the difference in the phenotype between males and females of the same species (e.g., body size, courtship behavior

traits related to fertilization

traits related to differences between the sexes in terms of body size, ornaments, color, and courtship

Body size differences between sexes are common in animals; there has been selection for an increased number of gametes or an increase in parental care in one of the sexes.​

the hypothesis that an individual chooses a mate that possesses a superior genotype.​

​

the hypothesis that an individual chooses the healthiest mates.​

​

when selection for preference of a sexual trait and selection for that trait continue to reinforce each other; continues until males run out of genetic variation.​

the greater the handicap an individual carries, the greater its ability must be to offset that trait.​

interactions with members of one’s own species, including mates, offspring, other relatives, and unrelated individuals.​

A group may be able to fend off predators better than an individual.​

​

the reduced, or diluted, probability of predation to a single animal when it is in a group. Probability of death = 1/group size​

More individuals watching for predators allows each individual to spend less time watching, and more time feeding.​

many individuals searching for food may be able to find rare food more easily (probability of prey capture increases in a group)

being social makes it easier to find potential mates because large groups attract the attention of females

the location of an animal aggregation to put on a display to attract the opposite sex

groups of animals are more conspicuous to predators

The risk of parasites increases in groups; high densities can increase the rate at which diseases spread.​

Larger groups are better able to locate food, but that food must be shared among all members.​

Living in groups can lead to aggression among members.​

any area defended by one or more individuals against the intrusion of others.​

a social ranking among individuals in a group, typically determined through contests such as fighting or other contests of strength or skill.

Every interaction between two individuals has the potential to affect the fitness of both individuals, either in a positive or negative way.

Donor

Recipient

the individual who directs a behavior toward another individual as part of a social interaction.​

the individual who receives the behavior of a donor in social interaction.​

when the donor and the recipient of a social behavior both experience increased fitness from an interaction (e.g., when a herd of lions kill prey).​

when the donor of a social behavior experiences increased fitness and the recipient experiences decreased fitness (e.g., competition for food).​

when a social interaction reduces the fitness of both donor and recipient (does not occur in natural populations).​

social interaction that increases recipient fitness and decreases the fitness of the donor.​

the fitness than an individual gains by helping relatives (with which it shares genes through a common ancestor) pass on copies of their genes.​

the sum of direct fitness and indirect fitness

selection that favors direct fitness

selection favoring indirect fitness

the numerical probability of an individual and its relatives carrying copies of the same genes from a recent common ancestor.​

1. Several adults living together in a group​

2. Overlapping generations of parents and offspring living together in the same group​

3. Cooperation in nest building and brood care​

4. Reproductive dominance by one or a few individuals, and the presence of sterile individuals​

individuals within a social group sharing a specialized form of behavior.​

the dominant, egg-laying female in eusocial insect societies; typically mate once during their lives.​

a sex-determination system in which one sex is haploid and other sex is diploid.​

no effect for animal 1, negative effect for animal 2

no effect for animal one, positive effect for animal two

negative effects for both animals

beneficial for both species

• predator prey

• plant/herbivore

• parasitoid/host

• parasite/ host

Any substance or factor that is both consumed by an organism and supports increased population growth rates as its availability increases​

• Consumed, availability decreases​

• Used for maintenance and growth​

• Reduced availability reduces population growth​

A resource whose availability quantity cannot meet a population’s requirement for it (carry capacity)

Ectoparasites live on the outside of an organism.​

Endoparasites live inside organisms.

Intracellular: live inside the cells of a host​

Intercellular: live in spaces between cells of a host​

a newly discovered or rare disease that increases in abundance.​ (ex white nosed bat syndrome)

Mechanism of transmission​

Mode of entering the host​

Ability of parasite to jump between species​

Existence of reservoir species​

Counterattacks to host’s immune system​

when parasite moves between individuals other than parents and offspring

when a parasite is transmitted from a parent to its offspring

the simplest model of infectious disease transmission that incorporates immunity.​

S = Number of individuals susceptible to a pathogen​

I = Number of individuals that become infected​

R = Number of individuals that develop resistance​

​

b = rate of transmission (via contact) between individuals​

g = rate of recovery and development of immunity​

(SxIxg)/ (Ixb)

SxIxg = rate of infection

lxb = rate of recovery

when two or more species continue to evolve in response to each other’s evolution

• generalists

• specialists

• obligate mutualists

• Facultative mutualists

a species that interacts with many other species.​

a species that interacts with one other species or a few closely related species.​

two species that provide fitness benefits to each other and require each other to persist.​

two species that provide fitness benefits to each other, but the interaction is not critical to the persistence of either species.​

fungi that surround plant roots and help plants obtain water and minerals.​

fungi characterized by hyphal threads that extend far out into the soil and penetrate root cells between the cell wall and the cell membrane.​

fungi characterized by hyphae that surround plant roots and enter between root cells but rarely enter the cells.​

a type of endomycorrhizal fungi that infects a tremendous number of plants including apple trees, peach trees, coffee trees, and grasses.​

a model of predator-prey interactions that incorporates oscillations in predator and prey populations and shows predator numbers lagging behind those of their prey.​

​

dv/ dt = rv - cvp

v= number of prey​

P = number of predators​

c = probability of an encounter between a predator and prey leading to the prey’s capture

dp/dt = acVp - mp

a = the efficiency of a predator converting consumed prey into predator offspring​

m = per capita mortality rate of predators

• prey population stable when predator population equals r/c

• If there are more predators when there are more predators than r/c then prey populations are decreasing ​

• When there are less predators than r/c than prey populations are increasing ​

• When prey population = m/ac then predator population is stable (0)

• ​When prey is greater than m/ac then predator population increases

• ​When prey is less than m/ac then predator population decreases ​

vertical line - predator

horizontal line - prey

the simultaneous trajectory of predator and prey populations.​

the point at which the equilibrium isoclines for predator and prey populations cross.​

the relationship between the density of prey and an individual predator’s rate of food consumption.​

predators rate of consumption rises linear despite prey density (they will always eat all of the prey items ​

when a predator’s rate of prey consumption begins to slow as prey density increases and then plateaus; often happens because predators must spend more time handling more prey or become satiated.​

Any increase in prey density is associated with a slowing rate of prey consumption.​

when a predator exhibits low, rapid, and slowing prey consumption under low, moderate, and high prey densities, respectively.​

​

Low consumption at low prey densities may occur for three reasons: ​

​

1. Prey can easily find refuges to hide.​

​

2. Predators may have less practice at locating and catching prey but develop a search image at higher prey densities.​

​

Search image: a learned mental image that helps a predator locate and capture food.​

​

3. Predators may exhibit prey switching by changing their diet preferences to the more abundant prey.​

• active : spend most of their time moving around looking for prey (e.g., birds foraging on lawns for worms).​

• ambush : (sit-and-wait) hunting strategies lie in wait for a prey to pass by (e.g., chameleons waiting for insect prey).​

• avoidance (running away, refuge, etc.) - behavioral

• Armor - Physical defense

• Mobbing - behavioral

• Chemical (poison) - behavioral and structural

camouflage that either allows an individual to match its environment or breaks up the outline of an individual to blend in better with the background (e.g., katydids, horned lizards).​

warning coloration

when ​palatable species evolve warning ​

coloration that resembles ​unpalatable species (e.g., hoverflies and hornet clearwings ​resemble the common wasp).​ ( copycat mimic)

when several unpalatable species evolve a similar pattern of warning coloration (e.g., several species of poison dart frogs have evolved similar warning coloration).​

mimicking the sounds of a dangerous species when you are not dangerous.

Structural defenses: sharp spines and hair

Chemical defenses: sticky resins and latex compounds

Tolerance: increases the production of plant tissues