Community Structure Flashcards
ecological community
group of species living together in the same place and time
can vary greatly in size and scope (whole desert vs. pitcher plant)
community boundaries are not always clear - can be defined arbitrarily
taxonomic groups
groups of related species, such as family or genus
guilds
species that use the same set of resources
functional groups
species that carry out similar processes
what they create or do
biodiversity assessed by
- studying trophic networks
- trophic networks or webs are organized based on what they eat and what eats them
- each trophic level contains species that have similar ways of obtaining energy
primary producers
convert energy from solar radiation into biological energy through photosynthesis
primary consumers
herbivores that eat primary producers
secondary consumers
organisms that eat herbivores
plants and algae
primary producers
grouping them together via concept of functional groups -> convert solar radiation into biological energy
herbivory
primary consumers eat primary producers
guild grouping -> all primary consumers use the same set of resources (plants)
carnivores
secondary consumer
eats other animals
omnivore
feed on multiple trophic levels
primary producer, primary consumer, other consumers
detritivores or decomposers
consume detritus and return nutrients to the community
(plant matter, waste, remains)
create soil
scavengers
eat parts of larger tend organisms
tend to be larger themselves
whale fall community
- come together when a large marine animal dies and sinks
- scavengers (fish, hagfish, sharks, octopus) eat the bits of flesh off of the whale
- detritivores (worms, sea stars, bacteria) filter remaining particles out of the water and sediment
disperse away and search for another
communities vary
in species number and composition
community structure
patterns of species diversity and composition at the community or local scale
species diversity
metric that combines species richness and species evenness
one way of quantifying community structure
biodiversity
- describes levels of diversity from genes to species to communities (interconnected)
- greater genetic diversity leads to greater population fitness, which promotes species diversity
- more community types = more diversity
Shannon diversity
combines species richness and evennness
-sum[pln(p)]
alpha diversity
local site or community
species richness in community
gamma diversity
larger region i.e biome
species richness in region
beta diversity
connects alpha and gamma
measurement of relative diversity of different areas within a region
= gamma/alpha
