Population and community Flashcards
What are the management of populations
Increase population size
-endangered species
Decrease population size
-pests
maintain population size
-management
What is population?
Group of individuals of same species in same area at same time
-rely on same resources
-interact
-interbreed
Factors that affect population size
Abiotic factors
-Sunlight and temperature
-water
-Soil/nutrients
Biotic factors
-Prey
-competitors
-predators
-parasites
Population growth rates?
Sex ratio
generation time
age structure
Tradeoffs survival vs reproduction
The cost of reproduction
-Increasing reproduction may decrease survival
What are K-selected
-late reproduction
-few offspring
-invest a lot in raising offspring
What are r-selected
-early reproduce
-many offspring
-little parental care
What are density-dependent and density-independent
Density-dependent
Competition: food
mates, nesting, sites
Predators, parasites, pathogens
A death rate that increases population
Density independent
Abiotic factors
sunlight temperature
rainfall
birth rate that does not change
what is a community?
All the organisms that live together in a place
What is competitive exclusion?
No two similar species can occupy the same niche at the same time.
Interspecific interaction
-Symbiotic interactions
-Symbiotic interactions -both harmed
competition (-/-)
compete for limited resource
competitive exclusion
Interspecific interaction
Predation parasitism
One benefit other harmed (-/+)
Interspecific interaction
Mutualism
(+/+) Both help each other Liches (algae and fungus)
For example a clown fish
Interspecific interaction
Commensalism
Commensalism
barnacles attached to an whale
one species benefit other species is not harmed but no benefit
What are the Anti predator adaptations?
Hide from predators
Warn predators
Hide from predators
-avoid detection
-camouflage
Warn predators
-Advertise how undesirable you are as prey
-Aposematic coloration
Apo-away
What are the defense mechanisms?
Camouflage
cryptic coloration
What is Batesian mimicry
Harmless species mimic a harmful model
Harmless mimics harmful something
What is Mullerian mimicry?
Two or more protected species look like each other
-Aposematic species come to resemble each other
What does greater biodiversity offer?
-more food resources
-more habitats
-more resilience in face of environmental change
avoidance of drastic change to environment
What are keystone species
Keystone species
-increase diversity in habitat
-they keep population in check
What is Ecological succession?
Sequence of community changes
Transition in species composition overtime
What is primary sucession
Begins virtually lifeless area without soil
What is secondary succession?
Existing community but the base soil is still intact
what is resource partitioning
The niche that enables similar species to coexist in a community
What is cryptic coloration
Camouflage makes prey difficult to see
what is climax forest?
(The end)
Plant community dominated by trees
the final stage
solar energy
temperature
rainfall
fertility and death of soil
