Community Basics
Multiple populations of different species living and interacting in the same area
What is an ecological community?
Two species competing for identical resources cannot coexist
What is the competitive exclusion principle?
Biodiversity is highest here
Where are tropical regions near the equator?
Producers → Primary consumers → Secondary consumers → Decomposers
What is the correct energy flow in an ecosystem?
Very low precipitation, extreme temperatures
What is a desert?
The variety of species in a community and their relative abundance
What is community diversity?
A relationship where both species benefit
What is mutualism?
A species with a disproportionately large effect on its ecosystem
What is a keystone species?
Organisms that make their own food
What are autotrophs?
Grasslands with scattered trees and seasonal rainfall
What is a savanna?
The process of change in species composition over time
What is community succession?
A relationship where one benefits and the other is harmed
What is parasitism?
A species that creates or maintains habitat for others
What is a foundation species?
A linear feeding sequence
What is a food chain?
Cold biome with coniferous forests
What is a boreal forest?
Succession that begins on bare rock
What is primary succession?
Back-and-forth evolutionary adaptations between interacting species
What is reciprocal evolution?
Example: sea otters controlling sea urchin populations
What is a keystone species example?
Interconnected feeding relationships
What is a food web?
Frozen soil (permafrost), very cold
What is the Arctic tundra?
Succession that occurs after a disturbance but soil remains
What is secondary succession?
Predator-prey populations influence each other's size over time
What is population cycling (predator-prey dynamics)?
The variety of life at genetic, species, and ecosystem levels
What is biodiversity?
Toxins becoming more concentrated up trophic levels
What is biomagnification?
Transition zones between freshwater and marine ecosystems
What are estuaries?