The type of organism whose removal or addition can trigger a trophic cascade.
What is a top predator?
The group of organisms that forms the base of every trophic pyramid.
What are producers?
The process by which energy is transformed but never created or destroyed, according to the first law.
What is energy conservation?
The structures built by beavers that dramatically alter water flow.
What are dams?
The population level predators help maintain in prey species.
What is a balanced or stable population?
The phenomenon in which predators reduce herbivores, allowing plant populations to rebound.
What is a top‑down cascade?
The approximate percentage of energy transferred from one trophic level to the next.
What is 10%?
The measure of disorder that increases during every energy transfer.
What is entropy?
The marine mammal that protects kelp forests by controlling sea urchin populations.
What is the sea otter?
The term for predators that have an outsized influence on ecosystem structure.
What is a keystone predator?
The herbivore whose population declined when wolves were reintroduced to Yellowstone.
What are elk?
The characteristic population size of organisms at the top of a trophic pyramid.
What is small or low population size?
The form in which most energy is lost due to the second law of thermodynamics.
What is heat?
The large animals that shape savannas by knocking down trees.
What are elephants?
The position apex predators occupy in a food chain.
What is the top trophic level?
The term for ecological effects that spread across multiple trophic levels.
What is a cascading effect?
The type of pyramid that represents the total mass of organisms at each trophic level.
What is a biomass pyramid?
The principle that explains why food chains rarely extend beyond four or five trophic levels.
What is energy loss at each transfer?
The type of habitat created by coral reefs.
What is a complex marine habitat or reef ecosystem?
The improvement in prey populations that results when predators remove weak or sick individuals.
What is increased genetic health?
The ecological consequence in which biodiversity decreases after a top predator is removed.
What is ecosystem collapse or reduced biodiversity?
The reason energy decreases as you move upward through trophic levels.
What is energy loss as heat and metabolic use?
The thermodynamic limitation that keeps predator populations smaller than prey populations.
What is limited available energy?
The ecological benefit ecosystem engineers provide by creating new niches.
What is increased biodiversity?
The ecosystem instability that can occur when predators are removed.
What is a trophic cascade?