Lecture II. Species Distributions, Biomes Flashcards
What determines species distributions?
Both ecological factors and evolutionary history
ex. kangaroos only found in australia bc isolated, dispersal limited, and habitat limited
Define dispersal
the movement of individuals away from centers of high population density or from their areas of origin
Dispersal and dispersal limitations contribute to ____
global distribution of species
___ affects distribution
dispersal, biotic factors, abiotic factors, ecological factors, evolutionary species
what do natural range expansions show us (mountains)
the influence of dispersal on distribution, mountains can act as barriers to dispersal
Define species transplants
- organisms that are intentionally/accidentally relocated outside their original distribution, can disrupt communities/ecosystems to which they have been introduced. invasive species = non native; will cause environmental harm or harm to human health.
Define biome
a major type of biological assemblage
how is a biome determined on land? In water?
on land: temperature and rainfall (and seasonality)
in water: temperature, depth, salinity
what are the two fundamental aspects of biomes?
primary productivity and biodiversity
Define primary productivity
rate of plant production of biomass (amount of plant growth that is occurring in a given area over a given time)
Define biodiversity
number of species
If the same biomes in different regions of the world have different species with similar characteristics. That is an example of what?
Convergent evolution
Define convergent evolution
the evolution of similar features/growth forms among distantly related species in response to similar selection pressures
Three types of terrestrial biomes include
tundra, desert, and tropical forest
- determined by climate, (avg percipitation and temp)
Define disturbance
An event such as a storm, fire, or human activity that changes a community
ex. fires that can kill woody plants and maintain vegetation of a savanna and hurricanes creating openings in forests allowing different species to grow
8 types of terrestrial biomes
1) tropical forests (rain forests and dry forests)
2) temperate broadleaf forests
3) northern coniferous forest (Taiga)
4) chaparral
5) savanna
6) temperate grasslands
7) deserts
8) tundra
Drivers of species distribution are
evolutionary history and ecological features (dispersal [mountains] + biotic factors [species interactions])
Know temperature patterns (emphasis on this), precipitation patterns, and disturbance patterns of each biome
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compare contrast biome questions and ask common characters of some questions / know general location (not too many questions about biomes on the exam)
…
intertidal zones
next to the shore, submerged and exposed by the tides
Distribution
how a biological taxon (species) is arranged spatially
Dispersal
Movement of individuals away from centers of high population density or from their area of origin
Species transplants
organisms that are intentionally or accidentally moved out from their original location into a new environment
Biomes
a large scale biological community shaped by the physical environment they are found in
