Lecture 11 + 12 Flashcards
True or false: Parasite & host populations can fluctuate in ways that are similar to predator-prey population cycles
True
In the myxomatosis-rabbit system, what are the two vectors?
Mosquitos and fleas
Metapopulation
Refers to patchiness in a population that allows it to function like many connected smaller subpopulations.
If a plant evolves a defensive chemical to ward off herbivory how do we expect an insect herbivore to evolve?
The insect herbivore may evolve resistance to the chemical
True or false: A virus is likely not spreading if R0 (R nought) is much greater than 1
False
Exploitation interactions
An interaction that benefits one individual at the expense of another (ex. interactions with +/- outcome)
Includes: predation and herbivory (grazing); parasitoidism and parasitism this lecture
Parasitoids
- insect that lays one or a few eggs on or in a host organism, which the resulting larvae remain with, consume, and kill in the process
- invasion of the host is similar to a parasite
- functionally equivalent to a predator
Parasites are found in many groups
Viruses, bacteria, protists, fungi, plants, prions, worms (flatworms, roundworms, segmented worms, etc.), arthropods (crustaceans, insects, ticks), and vertebrates (mammals, birds, fishes)
Interaction: common cold and humans
Low lethality, high intimacy
Interaction: flea and dogs
Low lethality, medium-high intimacy
Interaction: vampire bat and cows
Low lethality, medium intimacy
Interaction: deer and bluegrass
Low lethality, low intimacy
Interaction: ebola and humans
Medium lethality, high intimacy
Interaction: raccoon and blackberries
Medium lethality, low intimacy
Interaction: wasp and caterpillars
High lethality, high intimacy
Interaction: trout and small minnows
High lethality, low intimacy
Interaction: predators
High lethality, low intimacy
Interaction: herbivores (grazers)
Low lethality, low intimacy
Interaction: parasites
Low lethality, high intimacy
Interaction: parasitoids
High lethality, high intimacy
Interaction: omnivores
Medium lethality, medium intimacy
How numerous are parasite species?
There are more species of parasites than all non-parasite species combined
Parasite species are abundant
Categorizing parasites: micro vs. macro
Rule of thumb: you see individual macroparasites with a “naked eye”
Parasites
A relationship in which an organism lives on the tissue of its hosts, often reducing the fitness of the host, but not generally killing it