Lecture 4b- Animals and their Environment

physical traits of predators

• highly mobile and fast

• well-differentiated front and back

• sophisticated sensory structures to track prey

• spend a lot of time looking for food, less time eating

grazers

• mobile

• spend a lot of time eating (less time looking)

• process large amounts of low quality food

deposit feeders

• “dirt cleaners”

• live in or on soft substrates like mud

• need to process large amounts of low quality food MIXED with lots of sediment

Surface Deposit Feeders sweep the area around them for organic matter

Burrowing Deposit Feeders live in what they eat and are specialized for digging and moving through tunnels

Filter Feeders

• Filter food from surrounding fluid

• Fluid must move relative to the animal or the food would be rapidly depleted 

sessile filter feeders

• animal is stationary, fluid moves

• some pump water through their bodies and filter it internally

• some use external structures to comb food from fluid

parasites

• animal lives in its prey

• complex lifecycle to facilitate transmission

• strategies to evade host immune systems

meiofauna

• small

• mix of grazers, predators, etc

• live between grains of sand (no meio da areia)

fundamental niche

the “hypervolume” of environmental resources and conditions in which an organism can be successful

• the full range of environmental conditions and resources a species can potentially use if there were no competition from other species or other limiting factors like predation

realized niche

subset of the fundamental niche that the organism actually inhabits