Gen Eco: Chapter 15

Define Predator

-Organism that kills and partially or entirely consumes another individual

-Diet is animal tissues

-Dont see as many specialists compared to herbivores

-Lion

Define Herbivore

-Organism that consumes producers such as plants and algae

-Range is narrow (lots of specialists)

-Doesn’t typically eat whole foods, maybe just part of a living plant

-Caterpillar 

Define Parasitoid

-Organism that lives within and consumes the tissues of a living host, eventually killing the host

-Often an insect host is the diet

-Range is narrow (typically certain species that this parasitoid laying its eggs in)

-Parasitic Wasps

Explain Mesopredators

-Relatively small carnivores that consume herbivores

-Coyotes, Weasels, Feral Cats

Explain Top Predators

-Typically consume both herbivores and predators

-Mountain Lions, Sharks, Wolves

Explain relationship between Top Predators and Mesopredators 

-Humans have reduced top predators, allowing mesopredators to expand their range 

-Removal of Top predators, Wolves Dingos Feral Dogs, leads to expansion of Mesopredators, Coyotes or Fox 

What was the Carl Huffaker experiment

-Created various interations to study growth and crashes

-Arrangement of a tray with balls and oranges mimiced Metapopulation 

Predator = Western Predatory Mites

Prey = Six-spotted mites 

Explain Mesopredator Release

-Rapid increase in population of mesopredators after removal of top predators from ecosystem

-Increase in mesopredators due to the loss of top predators

-Has dramatic effects on mesopredators prey pop

Explain the results from the Carl Huffaker study

Example without predators = Prey populations reached high numbers

Example with Predators = Both populations went extinct (predator consumed ALL prey)

-Spreading out the orange on the tray made it harder for the predators to find the prey (went extinct slower)

Environment more complex = predators couldnt find prey as easily

Unable to find prey easily = Stable predator-prey population cycle achieved

What is the Lotka-Volterra Model

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

What do you have to have for the Lotka-Volterra Model

-Number of prey

-Number of predators

-Probabilty of an encounter between predator and prey leading to preys capture 

-The efficiency of predator converting consumed prey into predator offspring 

-Mortality of predators 

Explain what the Lotka-Volterra Model means for prey and predators

-Growth of prey populations depend on the growth rate and rate of individuals killed by predators

-Growth of predators depend on the growth rate of predators

-When addition of prey is balanced by the consumption of prey, the prey population is stable

How to interpret Equilibrium Isoclines

-Decrease in prey populations = decrease in predators

-Decrease in predator = increase in predator

-Increase in prey = increase in predator

-Increase in predator = decline in prey

Define Equilibrium Isocline

-AKA Zero Growth

-Population size of one species that causes the other species to be stable

-Goes in a cycle 

Name different prey adaptations to predators and herbivores animals

-Physical (spines)

-Behavioral (Ox facing forward in a cicle protecting young ones)

-Chemical (Beetles spraying chemicals at predators)

-Doesnt want to be spotted (Crypsis and Warning coloration)

-Mimicry

Name different prey adaptations to predators for Plants

-Masting (producing more seeds than needed this way some will survive)

-Physical Defense (Spikes on cactus)

-Induced Defense (Defense that takes place after herbivory has happened) (Once chewed on, will release chemical to make rest of plant taste nasty)

-Compensation (After part is removed, will produce more flowers) (The more clippings you have, the more compensation the plant does)

Define Crypsis

-Camouflage that allows an individual to match its environment or breaks up the outline of an individual to blend in better with the background 

Define Warning Coloration

-Aposematism

-Distastefulness evolves in association with certain colors and patterns

Define Bayesian Mimicry

-Palatable species evolve one in coloration that resembles unpalatable species

-Coral snake is poisonous but the King snake isnt, king snake has similar coloration to confuse predators

Define Mullerian Mimicry 

-Several unpalatable species evolve a similar pattern of warning coloration 

-Several species of poisonous dart frogs have evolved similar warning coloration 

Explain the Landscape of Fear

-Idea of Non-Consumptive effect of just how the presence of a predator is causing these different impact

-The fear of predation causes changes in prey including behavioral morphological and physiological

Examples: -Wolves, elk, and bison in yellowstone

-Elk began to graze less bc of introduction of wolves and bison increase vigilance behaviors