Exam 3 Flashcards
If a predator must actively search for a prey, then what should be expected?
*E/(h+s)
energy gained should offset that used in searching & handling prey
what is a mechanical defense plants use againts mammal herbavores?
spines
What did ecologist Christen Raunkiaer observed in his studies?
that species abundances seem to have a regular distribution (inverted J)
the ratio between what determines the proportion of occupied patches at metapopulation equilibrium?
extinction & colonization
what does Leibig’s law of minimum states?
that there is one single limiting resource to population growth
what is taken into account for Lotka-Volterra-Gause competition model?
the carrying capacity of both competitors
how does digestive rate model differs from optimal foraging theory?
it focuses on digestion rate rather than ingestion rate
how to calculate lx or Ro?
- # alive divided by # alive initially
- Ro = sum of (lx. bx)
list the assumption of the Lotka-Volterra predator-prey model
- exponential growth of prey population
- removal of prey by predators only
- predator declines when starving
what applies to open communities?
chance association of organisms that are adapted to live in the same area
why do plankton population densities fluncuates more than sheep’s?
- they have a shorter life span & a higher turnover
- have higher intrincis mortality rate
- have higher reproductive rate
how is per capita birth rate calculated as?
total # of births over total # of individuals
What can be said about p. aurelia & p. caudalum?
p. aurelia is the stronger competitor
what does the sit-&-wait foraging mode depend on?
- high density of prey
- high prey mobility
- low predator energy requirements
if a mutant coffee plant has 15 times less caffeine than wild-type seeds, what can happen to it?
it’s pod would probably be more damaged by seed predators
What happened in georgii’s experiment?
in part 1, all preys was comsumed resulting in extinction of predators. in part 2, preys can now hide & recover, no extinction
what happens when rarefraction curves does not perfectly plateau?
some rare species may be missing
what is the most logical way to scale down a study with limited funding of DeVries’s butterfly diversity?
run the study with the same method for fewer years
what is the association between mycorrhizal fungi & land plants an example of?
trophic mutualism
the evolution of mutualistic interactions implies an increase in what?
fitness of both partners
define species abundance
the # of individuals of each species present in a given community
what is observed in Lotka-Volterra predator-prey model of snowshoe hare & lynx?
lynx cycles follow hare cycles & abundance peaks are slightly offset
in plant defence what does induced production of chemicals after damage suggest?
that defence has a cost
list Density-dependent factors that regulate population growth
- space
- norishment
- predators
- parasites
- diseases
what conclusion could be said about Robert Whittaker’s gradient analyses
despite differences in abundance, several plants appear across moisture gradient
what is the association between honey bee & flowering plants an example of?
mutualism
why is there a different value for carrying capacity for each subpopulation of spotted owls constituting a metapopulation?
because patches of suitable owl habitats vary in size
what is the phenomenon where perturbations at one level of trophic web spread across all other levels called?
trophic cascade
declare a statement that constitutes an aspect of metapopulation dynamics that is highly relevant to conservation biology
metapopulation is maintained even if some subpopulations go extinct
list Density-independent factors that regulate population growth
- temperature
- humidity
- catastrophic events
define species richness
the # of species present in a given community
what does the competitive exclusion principle state?
that 2 species with identical niches cannot coexist
what is exemplified when a tertiary consumer is introduced?
top-down control, given that relative biomass alternates between trophic levels
34) in a graph with 4 fluncuating lines, what does it show?
population cycles that vary independently for 4 different species
35) graph with 4 declining lines
all the above
what is a issue in ecology that Frank Preston explain with the concept of veil line?
sampling is imperfect & rarest species are missed
how is complex trophic webs more stable?
because it has less reliance on a single resource
unprofitable prey is mostly based on what fact?
that some prey are too hard to catch & may not be worth pursuing
39) food web of fish & dragonfly
all of the above
40) what can be said about rarefaction curve of a & b?
community a potentially has higher diversity than b
what is the key difference between exponential & logistic models of population growth?
unlike exponential, logistic include the concept of carrying capacity
write the definition of metapopulation
a group of subpopulations that exchange members through immigration & emigration
W4) what are the black line & gray portion on the bell shape graph?
- veil line
- rare species missed from sampling
name 2 key aspect of a sampling protocols that will ensure a good representation sample of species present in the area
a large sample size & area
write the definition of carrying capacity
the maximum population size that a environment can support
