Final - Lecture Slides (new material only) Flashcards
5 levels of ecology
Organism, Population, Community, Ecosystem, Biosphere
Organismal ecology (def.)
Study of adaptations that influence where and in what densities organisms exist
Population (def.)
group of individuals that live in same area at the same time
Community (def.)
multiple populations that interact in a particular area
Ecosystem ecology (def.)
treats biotic and abiotic factors as part of a complex system
Global ecology (def.)
studies influences on biosphere (where living things exist on earth)
Abiotic factors (def. and 3 examples)
non-living factors that influence where organisms exist (e.g., temperature, moisture/rainfall, variability)
Biotic factors (def. and 3 examples)
Food/prey, predators/parasites, hosts/host plants, competitors
Innate behaviors
performed without prior experience but can still be influenced by experience and learning
Fixed Action Patterns (FAP)
behavioral patterns that an organism will continue until completed, once they’ve begun
What causes FAP’s to begin?
A sign stimulus
Learning (ecological definition)
An enduring change in behavior based on experience
Proximate cause
mechanistic; asks “how”
Ultimate cause
ask “why,” have to do with evolutionary influences
Tinbergen’s four questions
- Immediate stimuli: what elicits a behavior?
- Development: how does behavior change over animal’s lifetime?
- Survival function: how does a behavior affect survival and reproduction?
- Evolutionary history: how does a behavior vary over the history of the animal?
What kind of question and what perspective is each of Tinbergen’s four questions?
- Proximate and short-term
- Proximate and long-term
- Ultimate and short-term
- Ultimate and long-term
Optimality
Do animals behave the way they “should” behave?
What do “normative” models tell us?
what “should” happen, often generally
What do “descriptive” models tell us?
Try to explain what happens in a particular circumstance
How to find optimal circumstance for something
Maximize difference between benefits and costs
Definition of ecology
Study of the distribution and abundance of organisms
Functions of ornaments
Signals, often indicator traits
Anisogamy
sexual reproduction by the fusion of dissimilar gametes
Why do males compete for females?
Female gametes are a limited resource of sorts (females have big gametes; males have small gametes and a lot of them)
Ordered or uniform distribution
(Variance/Mean)
Random distribution
(Variance/Mean) = 1
Clumped distribution
(Variance/Mean)»_space; 1
-lots of variation in nearest neighbor distance
When do we expect an ordered distribution?
Individuals are directly competing or defending a territory, and resources are evenly distributed
When do we expect to see a clumped distribution?
Resources are clumped (environment is patchy), or with social animals
What does N mean for mark and recapture?
total population (what we’re trying to find out)
What does m1 mean for mark and recapture?
number in the first sample; all marked
What does n2 mean for mark and recapture?
number in second sample, total
What does m2 mean for mark and recapture?
number in second sample that were captured before
Equation to find total population for mark and recapture
N = (m1*n2)/m2
Demography (def.)
study of factors that affect size and structure of a population
What causes population growth?
births and immigration
What causes population decline?
Deaths and emigration
Generation time (def.)
average time between mother’s and daughter’s first offspring
Type I survivorship curve
high survivorship until old age, then low survivorship
Type II survivorship curve
steady survivorship throughout lifetime
Type III survivorship curve
initial low survivorship, then high survivorship
Life history (def.)
traits related to survival, mating success, and fecundity
r selected species
low survivorship, high fecundity
k selected species
high survivorship, low fecundity
Life history trade-offs
an individual allocates resources or energy to different components of life history
Where do life history trade-offs come from?
Traits controlled by genes that increase one fitness component at the expense of another
Population growth formulas
∆N/∆t = (b-d)N = rN
Formula for total population growth, ignoring migration
B-D
or, total births - total deaths
Formula for per capita growth rate
(b-d) = r
or per capita births minus per capita deaths
What does it mean to have a per capita growth rate of
a) 0
b) >0
c)
a) b and d are equal; population is stable, no growth or decline
b) growth
c) population decline
What is instantaneous growth rate?
Growth rate at any given time
What is maximum r (r_max)?
Intrinsic rate of growth, or as fast as a population can grow in unlimited conditions (unlimited resources)
Formula for population at generation t
N_t = N_0(1+r)^t
What is one factor that often affects instantaneous growth rate?
Density (density dependent population)
Carrying capacity (def.)
K; the number of individuals an environment can support
Equation for logistic growth
∆N/∆t = rN(K-N)/K
Metapopulation (def.)
two or more subpopulations
Population structure (def.)
Extent to which subpopulations cannot interact through migration
Sink (def.)
∆N
Source (def.)
∆N>0 (population growth)
Predation species interaction
+/-
Herbivory species interaction
+/-
Competition species interaction
-/-
Irruption (def.)
much higher than usual sightings of owls in southern areas
Niche (def.)
range of resources an organism uses; the relationship of individuals in a species to all aspects of their biotic and abiotic environment
Competitive exclusion (def.)
one species drives the other locally extinct
Fundamental niche (def.)
range of conditions where we find an organism in the absence of predators or competition
Realized niche (def.)
niche in the presence of predation and competition
Niche differentiation (def. and result)
When species niches do not overlap; natural selection favors individuals that do not compete
Aposematism (def.)
warning coloration
Mullerian mimicry
two or more toxic/venomous animals develop similar appearances and receive mutual benefit
Batesian mimicry
non toxic/venomous mimic looks like poisonous model and the mimic benefits; only works when mimics are relatively rare
Inducible defense (def.)
physiological or developmental (growth) response to predation and herbivory
Top-down control (def.)
predators limit herbivore populations
Bottom-up control (def.)
plants limit herbivore populations
What is a profound consequence of range shifts for species?
Hybridization
Dilution effect
loss of biodiversity means higher disease risk in humans
Rescue effect
diversity can “rescue” infection; higher diversity can lead to development of a better reservoir
Island biogeography: large islands have more ____ than small islands
species
Gross Primary Productivity (GPP)
total chemical energy produced in a given area/time
Net Primary Productivity (NPP)
chemical potential energy stored as biomass
Trophic levels (bottom to top)
decomposer -> primary producer -> primary consumer -> secondary consumer -> tertiary consumer
What direction do arrows go in a food web?
Consumed to consumer
Biomagnification (def.)
higher concentrations at higher trophic levels (could be concentration of something toxic)
Trophic cascade (def.)
when changes in high trophic levels influence trophic levels two or more links away
Hyper- or eutrophication (def. and cause)
too much food, caused by fertilizers at high concentrations
Primary succession (def.)
removal (or covering) of soil and soil community, and organisms above the soil
Secondary succession (def.)
does not remove all soil and soil organisms
Pioneering species (def.)
can grow in highly disturbed areas, devote much of their resources to reproduction
Facilitation (def.)
presence of (early) species improves chances for later species: stabilizes soil, fixes nitrogen
Tolerance (def.)
presence of given species does not affect chance of subsequent species establishing
Inhibition (def.)
presence of a given species reduces chances of later speces
Species richness (def.)
number of species
Species diversity (def.)
takes into account prevalence of different species
