6 Flashcards
First, second, third, and fourth level of a food web?
Primary producers -> primary consumers -> secondary consumers -> tertiary consumers
Interaction web?
Indication of competition, facilitation, and interactions between a community.
Food web?
Trophic interactions only.
Direct interactions?
One species have some impact on another.
Indirect interactions.
When three species are involved, then one species may not do anything to the third, but if one species does something to another, then there may be an interaction with the third.
Interaction modification? (2•)
•When an interaction is not direct to a particular species, •because it doesn’t completely eliminate a problem, but just makes it harder.
Trophic Cascade?
A carnivore eats an herbivore (a direct negative effect on the herbivore)
Trophic Facilitation?
A consumer is indirectly facilitated by a positive interaction between its prey and another species.
Competitive network?
A outcompetes B which benefits C which outcompetes A which benefits B which outcompetes C: A cycle
Competitive Hierarchy?
A outcompetes B but this does not benefit C because A also outcompetes C.
Keystone species?
strong effects because of their role in a community (like when a species cause a negative effect for another but also for a third species).
Ecosystem engineers
A creation of one species that benefit another to create a mutualistic interaction.
Foundation species?
Species contributing most of the spatial structure of the community, the competitive dominants.
Primary succession?
Starts from scratch and occurs when new substrate becomes available for the first time.
Secondary succession?
Follows a disturbance that leaves some components in a community.
Models of succession? (3•)
•Facilitation: Early successional species speed succession by improving conditions for later colonists.
•Inhibition: early successional species delay succession by interfering with later colonists.
•Tolerance: Early successional species have neither a positive nor negative influence on later colonists.
Diversity is the highest where in the disturbance frequency graph?
A line that crosses early, mid, and late disturbance frequency.
What happens if you never get disturbances?
Early succession species may go to extinction while late succession species will reach towards its carrying capacity.
Does herbivory and predation cause disturbance?
No, but the effects can be very similar.
Diversity peaks at intermediate levels of disturbance when?
- competitively inferior species are better at colonizing new patches, or…
- competitively inferior species are more resistant to the disturbance
