L5 Consumer-resource interactions Flashcards
when is the origin of consumers (heterotrophs) dated back to?
Precambrian, connected to the great oxigenation event
what is the hypothesis of where the first oxygen started coming from
deep sea nodules
when did endotherms start appearing
triassic
which thermal strategy requires the most intake of energy
endotherms
what other factors need to be considered when trying to determine consumer resource interaction rates (besides metabolic needs)
mode of locomotion, size and thermal physiology
what does the consumption rate (c) curve look like when food is scarce?
searching rate (a) dominates energy use
what does the consumption rate (c) curve look like when food is common?
most energy used on handling (h)
what is the equation by Holling 1959 for consumption rate
c = aR/(1+ahR)
what other things can be added into the conspution rate model to make the model more complex?
dimension, velocity, success, risk…
how do velocity and detection scale with size
they scale positively with consumer size
what is euclidian dimensionality of interactions and what effect does it have on the energy expended
depends whether consumer is looking for resource in 2D or 3D - eg antelope looking at grass is 2D, whereas bird hunting another bird is 3D, more energy expended in 3D
what effect does adding dimensionality have of the scaling of consumption rate with size
it is steeper, therefore consumption rate in 3D higher for same sized organism in 2D
what is the Boltzmann Arrhenius response of interactions on temperature
velocity of consumer and resource inscrease with temperature, handling time decreases with temperature and consumptions and metabolic rate also increase
what makes the existence of a large mammal like whales possible
large body mass supported in water - would not be possible on land
large body mass also possible becase whales are able to consume resoources in 3D
what effect do physiological mismatches have on consumer resource interaction
in certain conditions, one may outperform the other, therefore it may affect their behaviour and strategies
what is the Lotka-Volterra model and what is it dependent on
rate of change or prey population over time, temperature and size
what is Damuths law
the bigger you are the lower population density
what else can Lotka-Volterra model predict
with metabolic constraints, it can predict Damuth’s law, the opposite of prey population model is the predator population model
