Ecology: Distribution Flashcards
If a species is found here
It evolved hereIt evolved elsewhere and moved
If a species isn’t found
It went extinctIt never touched the area
Biogeographic regions
Based on similarities of organismsBoundaries are where composition changes dramatically
Climate
Long term average conditions
Weather
Short term conditions at a certain place and time
Temperature
Daily and seasonal cycles
Earth axis tilt
23.5 degrees
Different climate regions due to
Solar energy dispersion due to axis tilt
Air circulation for equatorial area
Hot air rises and cools and turns to rain
Air circulation for deserts
Cool air from tropic region falls and heats up
Air circulation for forest area
Air picks up moisture from desert and rises and rains
Air circulation for polar regions
Dry air from forest descends (cold dry deserts)
Terrestrial biomes based on
Dominant vegetation
Aquatic biomes base on
Physical and chemical differences
If a biome has similar traits, they are closely related
False
Climate determines _______ of biomes
Distribution
Large scale distribution patterns can be predicted from
Climate conditions
Large scale distribution patterns can also predict small scale
False
The transplant experiment can be used to
Define a dispersal limiting factor
A successful transplant means
Organism lives and reproduces, and there IS a barrier to dispersal
A failed transplant means
Organism dies, living conditions are poor and it is NOT a barrier to dispersal
To validate an experiment, you MUST have a
Control
Biotic interactions that take part in dispersion
Competition and predation
Indications of competition
One sp disappears and the other takes a larger rangeThere are sharp boundaries
Balanus is
A large barnacle
Chthalamus is
A small barnacle
Thais is
A predatory snail that eats barnacles
Take into account the _____ stage of organisms in dispersal
Developmental
Main abiotic factors limiting distribution
TemperatureWater (pH/salinity/current/oxygen)LightSoil structure
Adaption
Long term; evolutionary
Acclimation
Short term B or P change to adapt
Periodic disturbances are
Natural disasters
Infrequent natural disasters have what affect on organisms
A large impact because organisms don’t have a chance to adapt
Frequent natural disasters have what affect on organisms
Small impact, organisms get used to it and adapt
