Lecture 23: Trophic Relationships and Plant-Animal Interactions Flashcards
primary producers
plants
primary consumers
herbivores
secondary consumers
predators (carnivores who eat herbivores)
tertiary consumers
predators who eat other predators (sec. consumers)
decomposers
eat dead organic matter and return nutrients to external environment
Why is there more biomass in lower trophic levels
inefficient transfer of energy
food chain and food webs
drastic oversimplifications, only shows trophic interactions (where one animal eats the other) and not other interactions like gamete dispersal
Various names for plants
- primary producers
- autotrophs
trophic interactions are…
direct effects
indirect effect
one species alters the effect that another species has on a third
trophic cascades
interactions between two trophic levels cascade to a third trophic level
ex. carnivores eating herbivores reduces amount of herbivory thus helping plants.
HSS Green world hypothesis
top down control
What’s stronger, indirect or direct benefits?
Trick question, indirect benefits can be as strong as direct but it depends on the interaction strengths
Difficulties associated with herbivory
- plant tissue hard to break down (indigestible without microbial symbionts)
- plant tissues heavily defended against herbivores
Why are there so many species of plants???
Coevolutionary arms race between plants and insect herbivores responsible for much of biodiversity (specialization is common)
