10_Predation and parasitism_BI370

Predation

A species interaction where one organism kills another for food.

Parasitism

A species interaction where one organism benefits at the expense of another, usually without killing it.

Mutualism

A type of species interaction where both organisms benefit.

Commensalism

A type of interaction where one organism benefits and the other is neither helped nor harmed.

Amensalism

A type of interaction where one organism is harmed while the other is unaffected.

Mesopredators

Mid-level predators that can also be preyed upon.

Apex predators

Top predators in an ecosystem with no natural enemies.

Encountering

Finding prey

Behavioral defensive strategies

Herding, schooling, sentinels, aggression

Coevolution

The process where two species evolve in response to each other.

Batesian mimicry

A form of mimicry where a harmless species mimics a harmful one.

Müllerian mimicry

A form of mimicry where two unpalatable species evolve to resemble each other.

Microparasites

Parasites that are microscopic

Macroparasites

Visible parasites

Endoparasites

Parasites that live inside their hosts.

Ectoparasites

Parasites that live on the outside of their hosts.

Intraspecific competition

Competition between individuals of the same species.

Interspecific competition

Competition between individuals of different species.

Predator-mediated coexistence

When predators allow multiple prey species to coexist by limiting the population of dominant species.

Morphological defense strategies

Sensory perception, hardened exterior, shedding parts, camouflage

Physiologic defense strategies

Chemical defenses, speed, toxins

Keystone species

Species that have a disproportionately large effect on their environment relative to their abundance.

Ecosystem engineers

Organisms that affect their environment significantly by altering habitat.

Handling

subduing and consuming prey

Herbivores

Specialists due to high handling time

Carnivores

Generalists, due to low encounter rates

Prey Model (N)

dN/dt = rN - aNP; r = intrinsic rate of increase; N = prey abundance; a = capture efficiency; P = predator abundance

Prey zero growth isocline

P = r/a

Prey zero growth isocline patterns

Below line, populations increase; above line, populations decrease

Predator Model (P)

dP/dt = baNP - mP; b = conversion efficiency; m = mortality rate

Predator zero-growth isocline

N = m/ba

Predator zero growth isocline pattern

To the left, population decreases; to the right, population increases

Symbiosis

Two or more species live together intimately with their fates linked