#12-Predation And Herbivory Flashcards
What is a parasite?
Organism that feeds in or on another organism
-cause spread disease
What is a parasitoid?
Insects that lay eggs on or in hosts
- babies hatch then kill the host
What are sit and watch predators?
Remain in one place and attack ore within striking distance
What are the two types of predators?
- Generalists
2. Specialists
Herbivores usually eat all ______ but some ______ in one part
Above ground of a plant , some herbivores specialize in a specific part
What are the 2 most nutritious parts of plants that are commonly eaten?
Leaves and seeds
What do herbivore do to plants when they consume their seeds?
Reduce growth reproduction and survival
- consuming entire genome
What is a brows line?
Can be seen under trees where feeding starts and stops due to the lack of leaves
What do predators exert on their prey?
Strong selection pressures in order to not get eaten
What is aposematic coloration?
Prey have bright colours and predators have learned not to eat them
What is crypsis?
Prey is camouflaged/ resembles background
What is mimicry?
Prey resembles another organism that is very fierce
What are 2 plant defences for not getting eaten?
- Masking - overwhelming one year will seeds and not the next
- Intime - plants hide from herbivores
What is compensation?
Removal of plant tissue stimulates new growth
How does early her ivory play a role in compensation?
If early, plant can replace the tissues lost.
But later in the season then it can not be replaced due to the lack of resources for growth
What are some structural defences that plants have?
Tough leaves
spikes
thorns
What are induced defences?
Produced in response to an herbivorous attack
What are secondary compounds?
Toxic chemicals to reduce herbivory
Why can some herbivores tolerate some plant toxins?
They have digestive enzymes that some other herbivores can’t tolerate
- abundance of food for them
What are exploitative interactions?
Have the potential to reduce growth, survival and reproduction
What can be caused by exploitative interactions?
Population cycles
- lag and increases
What happens when prey are too easy to find ?
Predators usually drive them to extinction
- leads to predator going extinct themselves
What is one cause that can cause population cycles?
3 way feeding relationships
What are predator population peaks?
When prey populations have reached their lowest levels
In terms of genotypes, what happens to the prey when there is a high predator density?
Resistant genotypes increase and the number of predators decreases
What is exploitation?
Relationship in which one organics benefits by feeding on or directly harming another organism
