ecology unit 2

photosynthetically active radiation PAR

400-800 nm, spectra important to photosynthesis

photosynthetic photon flux (PPF)

photons per unit time

photosynthetic photon flux density (PPFD)

photosynthetic photons per unit time per area

photon flux density (PFD)

photons per unit time per area

autotrophs use _____ sources of _____ and energy

inorganic, carbon

photosynthetic autotroph uses _____ as a carbon source and ______ as energy

CO2, sunlight

chemosynthetic autotrophs use ____ _______ as a carbon source and energy

inorganic molecules

heterotrophs use _______ ________ as sources of carbon and energy

organic molecules

light propagates through space as a ______; interact with matter as a particle 

wave

leaf area index (LAI)

total leaf area / projected ground area

photosynthesis reaction

6CO2 + 12 H2O —→ C6H12O6 + 6H2O

C3 photosynthesis

used by most plants

C4 photosynthesis

make up only 3% of terrestrial plant species but 25% of photosynthetic carbon gain 

CAM photosynthesis

limited to succulent plants, very low rates of photosynthesis

herbivores have low ____ and ____ concentrations in plants

nitrogen and phosphorous

carnivores

consumes nutritionally-rich prey

predators act as “_____ ______” for refinement of prey

selection agents

aposematic coloring

warning signal in a form of bright colors on organisms

batesian mimicry 

harmless species mimicking a dangerous specie 

mullerian mimicry

when 2 or more harmful species evolve in similar appearances 

detritivores

animal that feeds on dead organic material

photosynthesis ________ linearly with photon flux density at low light intensities, ______ more slowly with intermediate light intensities, and tends to _______ at high light temperatures 

increases, rises, level off (stops progressing in a straight line) 

optimal foraging theory

organisms are adapted to exploit resources as efficiently as possible

holling’s functional response model: type 1

feeding increases linearly with food density then levels off, little-to-no searching

holling’s functional response model: type 2

feeding increases rapidly then slows (rises with food density → encounters searching → reach satiation) 

holling’s functional response model: type 3

S-shape, related to searching THEN handling (searching is the limiting factor at low food density, searching is reduced and handling is important at intermediate density, levels off due to handling at high density) 

optimal foraging theory (animals)

energy is always limited, organisms allocate available energy, trade-off between searching/handling to optimize intake 

darwin’s theory of natural selection 

some individuals have a higher chance of survival than others in the same population due to physical/behavioral traits 

johann gregor mendel

did the garden pea experiment

allele

alternate forms of genes (dominant or recessive)

genotype

genetic coding based on which alleles are present

phenotype

physical expression or function based on genetic coding

ecotype

populations living in separate locations with significant environmental differences (with almost no exchange of individuals) 

ecotypes are still the same _____, but gene pools are genetically _____ from one other

same, distinct

ecotypes are more common in species with a broad _________ ________. 

ecological range 

hardy-weinberg principle

p² + 2pq + q² = 1.0

states that in a population, mating at random in the absence of evolutionary forces, allele frequencies will remain constant 

each variable in p² + 2pq + q² = 1.0 is:

p = homozygous dominant frequency 

pq = heterozygous genotype frequency 

q = homozygous recessive genotype 

fitness

measure of individual’s contribution of genes / number of offspring contributed by individual to future generations 

stabilizing selection favors ______ phenotypes

average

directional selection favors ________ phenotypes

extreme (leads to changes over time)

disruptive selection favors ______ phenotypes over _________ phenotypes 

2+, average (creates a bimodal distribution) 

genetic drift

random processes that can change gene frequencies in populations (especially in small populations) 

homozygosity refers to having inherited 2 __________ ______ of a particular gene or genetic marker (allele), one from each biological parent 

heterozygous refers to having inherited _______ versions (alleles) of a genomic marker from each parent 

inbreeding may be a major contributor to higher _______ rates in small populations

extinction

artificial selection is used to describe ________ breeding of domesticated organisms to produce/maintain desirable ______. 

selection, traits 

genetic engineering is the ________ / ________ of genes in domesticated organisms 

introduction/deletion 

evolutionary consequences of chemicals in agriculture

resistance among pests

behavioral ecology

study of social relations within organisms and the environment 

sociobiology

study of social relations; can significantly impact fitness of individual/populations

females produce _____ gametes (eggs/ova)

larger

males produce _____ gametes (sperm, pollen)

smaller

hermaphrodite: organisms that contain ______ and ______ functions

male and female

sexual selection: differing reproductive rates resulting from_______ ________ ________. 

differing mating success 

intrasexual selection

one sex competes over other males for females (INTRA = within a group) (ex: deer fighting with antlers) 

intersexual selection

mates express preferences and try to impress each other (INTER = between groups) (ex: colorful feathers) 

intra prefix

within a group

inter prefix

between groups

endler’s natural selection study

3 different pond experiment w/ guppies: high predation, low predation, no predation 

in endler’s natural selection study, it supports the hypothesis that predation ______ male “showiness” (spots) and moderates the effects of _______ selection 

reduces, intersexual 

evidence of non-random mating in both field and lab experiments are _______. 

present

cooperative breeding

when a “helper” raises a baby that is not their own (by blood)

inclusive fitness us an organism’s genetic success is believed to be derived from ________ and ______ behavior 

cooperation, altruistic 

inclusive fitness

genetic relatedness x reproductive benefit > cost to helper 

males that delay reproduction have ______ lifetime reproductive success

lower

females that delay reproduction have ____ lifetime reproductive success 

higher 

kin selection

evolutionary theory where an individual performs altruistic acts that benefit their genetic relatives (even at personal cost) to enhance survival and reproduction 

eusociality has 3 parts: __________ care, multiple _______ co-habiting, and divisions of _______ and non-________ workers. 

cooperative, generations, reproductive (ex: ant colony)

in a haplodiploid system, males develop from _________ eggs and are _______. females develop from __________ eggs and are _______. (FOR ANTS/BUGS) 

unfertilized, haploid, fertilized, diploid 

________ fitness and _______ selection are rational explanations for altruistic behavior in nature

inclusive, kin

density

number of individuals per unit of area

distribution

the shape, size, and location of the area a species occupies 

abundance

the total number of individuals of a species in a specific area

a _____ summarizes the environmental factors that influence the growth, survival, and reproduction of a species 

niche 

the niche of a species is determined by the _____ in which it lives and its accompanying ______ adaptations

habitat, behavioral

grinnelllian niche: determined by the ______ and its accompanying _______ adaptations 

habitat, behavioral 

eltonian niche: a species’ response to and effect on environment; species grow/respond to environment based on ______, _______, ______. 

resources, predators, climate 

hutchinson niche: ___-__________ hypervolume, where the dimensions are environmental conditions and resources 

n-dimensional

what happens to distribution patterns, organism interaction, and organism size as populations increase in density?

competition 

random distribution

an individual has an equal probability of occurring anywhere in an area

in random distribution, there are ______ interactions between individuals, and between individuals and local environment

neutral 

regular distribution

individuals are uniformly spaced through the environment

in regular distributions, there are _______ interactions between individuals and local depletion of resources

antagonistic 

clumped distribution 

individuals live in areas of high local abundance, which are separated by areas of low abundance 

in a clumped distribution, there’s an ________ between individuals or of individuals to a common resource 

attraction 

for many species, organisms within populations are distributed not only in space, but also in ______

time (migration, mating strats, competition, growth 

allelopathy: biological process where plants and microorganisms release ________ that impact the growth of other organisms

chemicals

in general, population density ______ with increasing organism size 

decrease 

commonness classification of rarity/vulnerability to extinction based on 3 factors:

1) ________ ________ ____ _________: extensive vs. restricted 

2) ________ ________: broad vs. narrow 
3) _______ _______ ______: large vs. small / broad vs. narrow

geographic range of species, habitat tolerance, local population size 

abundant species usually ______ distributed, rarer organisms usually have _______ distributions 

widely, small 

rarity I: ________ habitat range, _____ habitat tolerance, _______ local populations

extensive, broad, small (ex: tigers)  (ex

rarity II: _______ habitat range, _______ habitat tolerance, ______ populations 

extensive, narrow, large (ex: pigeons) 

extreme rarity

species close to extinction

extinction is a common ecological process, >____% of species are extinct 

99

founder effect: genetic drift that occurs when a ____ ______________ is isolated from a bigger one

small population

phenotypic plasticity: when a single genotype produces different __________ (physical, behavioral), depending on their environment

phenotype

changes in population size formula

r = In(Nt/No)/t

geometric growth occurs in _______ generations (ex: reproduce once and die) before next generation begins breeding

discrete

exponential growth is a __________ process where growth rate proportional to the surrent size, leading to a faster _______ (decrease/increase) over time compared to geometric growth 

continuous, increase 

conditions for exponential growth is typically begin life in _________ environments, invasion of new territory, ________ of transient, favorable conditions

favorable, exploitation 

exponential growth is limited by ______ __________.

carrying capacity (K)