Lecture Eighteen - Pollination Flashcards
What is the name given to the ripple effect in a species network?
Extinction cascade.
How can we estimate the number of extinctions in a network?
Remove a pollinator species and its links from a network, remove remaining plants without connection to pollinator and its links, etc.
What is attack tolerance?
The capacity of a network to sustain damage and still maintain its connections.
When is a plant in a network classed as viable?
If it is connected to a pollinator.
What is the redundancy hypothesis?
Each pollinator lost does not effect survival of plants
What is the rivet hypothesis?
Each time pollinator is lost, same numbers of plants are lost.
What is the keystone hypothesis?
System does not experience change until important pollinator is removed, leading to rapid collapse.
How many pollen grains are there on a flower?
60,000 - 100,000
For oil seed rape, how many pollen grains are needed?
30
Why are many plants not set up for self-pollination?
Due to inbreeding
For almost every system measured, what is the transfer efficiency?
1%
What is Cruden’s rule?
About there pollen grains on the stigma for every ovule fertilised.
What is the pollinator dependence?
The amount of yield that would be lost without the existence of bees and other pollinators.
Why does Alfalfa hay not need pollinators?
It is cut before bees can reach it.
Why do cucumbers not need pollinators?
They are all F1 hybrids.
