Final Exam Review Sheet
The final is comprehensive. I have compiled the following objectives which can be
used to help you study the material.
Remember to bring a calculator to the exam
First set of objectives are for chapters you have already been tested on.
Chapter 1
* Describe:
Homeostasis: Maintenance of a nearly constant internal environment in the midst of a
varying external environment; the tendency of a biological system to maintain itself in a
state of stable equilibrium
Shelford’s Law of Environmental Tolerance: different organisms survive or thrive in
varying environmental conditions. Too little or too much of a condition can be deadly;
organisms have a “sweet spot” where they leave the max # of surviving offspring
Leibig’s Law of the Minimum: Plant growth is controlled by the scarcest nutrient
Blackman’s Law: too much of a good thing can be deadly
Chapter 2
* Describe how air masses rise near the equator, what happens to the water vapor
carried as related to dew pt and adiabatic cooling and then where the air
masses descend, the direction they move across the earth's surface (coriolis
effect). Relate the ecosystems to the amount of moisture in the air masses as
the air masses rise and where they descend (i.e. ecosystems at the equator
and 30N and S latitude).
1. movement of air (why does air rise at the equator)
air rises at equator because it is warm. Earth’s radiation heats air molecules, making them
less dense, and lots of air molecules are H2O, which is a light gas
after it rises, it is pushed away from equator by more rising air, circulating heat around
the world. As the temperature decreases, the air cools and comes back down to the
surface.
2. Solar radiation warms air and water vapor- warm, moist air rises at equator - lower pressure
lowers temperature (adiabatic cooling) – hits dewpoint – rain causes RAINFORESTS – heat
carried away from equator – descends around 30 degrees -cools, density up, dry air creates
DESERTS
Chapter 5
* Use data to determine which mechanism is the likely agent (genetic drift, natural
selection or gene flow) causing changes in gene frequencies (water snake
example).
- Gene flow from snakes on mainland to snakes on near islands because some snakes migrate
out/get lost/etc.
* Calculate refuge size for a given organism using population genetic and
ecological information (water snake example).
-see ppt
Chapter 8
* Define and be able to work with the following population parameters: density,
structure (age pyramids, be able to interpret age pyramid for a growing,
stationary, declining population), and dispersion pattern (uniform, clumped and
random).
- Crude density is just organisms per unit of area sampled; isn’t super accurate
- Ecological density is organisms per unit of HABITABLE area; is more accurate
- Age structure is proportion of individuals in various age classes for any one year.
- Random means no interactions, uniform means animals are territorial, and plants are
competing for resources, clumped means there are social issues or patchy resources.
- Home range is spaced used by individual for food, shelter, + mates (not defended)
- Tend to overlap, increases as body mass increases, herbivores need more range
- Territory is defended and marked space, no overlap.
-Mean greater than variance = clumped
-Mean equal to variance = random
-Mean less than variance = uniform
Chapter 9&11 (logistic growth)&29
* Distinguish between the 3 types of survivorship curves (Type 1, 2, and 3)
- Type 1: High survivorship until old age (humans, elephants, dogs)
- Type 2: Constant decline (lizards)
- Type 3: High mortality early in life (sea turtles, octopus, some fish)
* life tables - know the basics (Nx, lx, dx, qx, sx). You should be able to calculate all
the values in a life table given either dx or Nx values.
-see flash cards
* Distinguish between exponential/geometric and logistic growth (carrying
capacity).
- Exponential growth makes a “J” shape as pop increases, not limited by environmental
factors/resources, density independent
-Logistic growth makes a “J” shape until it hits carrying capacity (aka S shape), limited by
environmental factors + resources, density dependent
* know for exponential/geometric models what values of r or would produce
positive, 0 or negative population growth (for example, if = 1, population
growth is 0).
- R = 1, population is stable; R > 1, population is declining; R < 1, population is
increasing
- = 1, population growth is 0; > 1, population growth is growing; < 1,
population growth is declining
* Calculate doubling time, r or , and t for exponential and geometric growth
models (you need to know these models also)
-See slide 8 of first ppt in binder
* Be able to graph density dependent/independent birth and death rates and relate
these to whether a population is growing, stable or declining
- see slides 24-26 of first powerpoint in binder
* Know characteristics of species (small range, large body size, etc) that make
them prone to extinction.
- Restricted geographic range: no other populations to help with recovery, susceptible to natural
disasters.
-Habitat specificity: the more specific a habitat needs to be, the less likely the species will be
able to spread out and grow; similar to ^
-Small local population: inbreeding and low adaptability are not great
-Food specialization: lose food, lose species (ex: koala and eucalyptus)
-Large body size: larger body size means larger home range/territory, and space is becoming
more and more limited due to human development
-Habitat fragmentation: creates small, isolated populations, each with a high probability of
extinction
Chapter 10
* Describe characteristics of r and K species.
- r species prioritize reproduction over biomass, tend to have shorter lifespans and
more offspring (ex: annual weeds)
- K species prioritize biomass over fast reproduction, tend to have longer lifespans
and less offspring (ex: trees)
* Define semelparity and iteroparity.
Semelparity: One set of offspring
Iteroparity: Multiple sets of offspring
Chapter 11
* Distinguish between scramble and contest competition.
-Scramble: Chaotic population oscillation (all suffer) – less resources overall, etc.
-Contest: Less chaotic population oscillation (some suffer) – best fit hoard food, etc.
* List several effects of intraspecific competition such as decreased fecundity,
increased age at first reproduction.
- Growth will decrease, less females will be reproductive, less fecundity, and the age at first
reproduction will be higher
Chapter 13 &14
* Define the various kinds of relationships between species (commensalism,
mutualism, parasitism, predation, competition)
-mutualism: + +
-commensalism: + 0
-predation: + -
-parasitism: + -
-competition: - -
-amensalism: - 0
* Distinguish between interference and exploitative competition.
Exploitative: what I eat you can’t eat (like scramble)
Interference: deny access to resource (like contest)
* Using graphs and vectors from the Lotka Volterra model of competition,
determine whether two species can coexist. Be able to create a graph of
competing species using information on their carrying capacities 𝛼, and 𝛼
coefficients.
-look at isoclines. If they intersect, they can coexist.
-Isocline is line from carrying capacity to a (point on x axis) or B (point on y axis)
-if under isocline, pop up – if over isocline, pop down
* Define the following as they relate to interspecific competition: niche partitioning,
character displacement, species population size changes, removal
experiments.
-niche partitioning = species with niche overlap developed specialization outside of
overlap to reduce interspecies competition
-character displacement = differences btwn species accentuated when near each other
geographically, not as prevalent when further away
-species population size changes = increase in one usually means decrease in
the other
-removal experiments = taking one species out of an area to see the effect on the
other species/ecosystem as a whole
Chapter 15
* Using graphs and vectors from the models of predator/prey interactions, describe
whether the system is stable, damped, unstable, stabilized with a refuge. Also
be able to identify k for the predator and prey.
-No modifications = circle, doesn’t account for amplitude change
-for the prey isocline - inclusion of carrying capacity and/or the Allee effect
-Carrying capacity: falls off at k
-Allee effect: falls off before pop reaches 0
-for the predator isocline - add carrying capacity and modify predator efficiency.
-Carrying capacity: falls off at k
-Efficiency: Efficiency and # prey needed for predator increase are negatively
correlated
* Be able to graphically determine the 3 different functional responses of predators
and the predators potential impact on the prey population. Combine
information on the functional response with the numerical response to get total
response. Using total response, describe the effect of the predator on the prey.
- Type 1: Prey density up, # prey eaten up (linear); prey pop hits maximum pred
can eat then % prey eaten drastically decreases like a spoon (filter feeders)
- Type 2: Prey density up, # prey eaten up (curved); prey pop hits maximum pred
can eat then % prey eaten drastically decreases in a curve (disk experiment,
many invertebrates)
- Type 3: Prey density up, # prey eaten up; prey pop hits maximum pred can eat
then % prey eaten slightly decreases (mostly vertebrates)
* determine for a type 2 functional response predator using the disc equation
handling time and search rate.
-see predator handout in folder
* Define optimal foraging and be able to determine from a graph of prey available
vs prey eaten whether the predator illustrated is an optimal forager.
- Energy intake > Energy to get/process
-Can be affected by size of prey
* Describe responses of prey to predation including various types of defenses
(chemical, mechanical, behavioral, coloration).
secondary compounds = chemicals used as deterrent (tannins reduce efficacy of
consumption, etc.)
predator satiation = make enough babies that predators will eat their fill before all
babies are dead
structural defenses = spines on cacti, etc.
warning coloration = bold colors mean toxic or unpalatable
Batesian mimicry = palatable species looks like unpalatable species
Mullerian mimicry = unpalatable species looks like another unpalatable species
Moment-of-truth defenses = do something or get eaten (gecko loses tail)
Chapter 17&18
* Define community
- All the species in a given area
* Be able to use Shannon diversity indices and Morisita’s Indices to compare
communities.
- Higher #s mean more diverse (Shannon) or higher similarity (Morisita’s)
* Discuss the influences of population interactions on community structure (i.e. like
the seastar’s keystone role in the intertidal community).
What is a keystone species and how it is determined in a community
-keystone species is a species that a community cannot exist without. It is determined
by removing species from a community to see if it collapses or not
Distinguish between top-down and bottom-up controlled communities.
-Top-down: top level keeps mid in check, stops mid from destroying bottom
-Bottom-up: bottom levels keep mid-levels in check, mid-levels regulate top
growth/decline
in communities, under what conditions would interspecific competition be unlikely (see
notes at end of interspecific competition where we had a caution about assuming
interspecific competition)
- Would be unlikely when population is regulated by density-independent factors
Chapter 19
* Define primary and secondary succession as well as autogenic and allogenic
processes in succession.
-primary succession: starting from scratch; no soil or immediate previous community
-secondary succession: community was destroyed but not the soil
-allogenic changes: prompted by change in physical environment
-autogenic changes: self-generated changes
* Know that some animal species are tied closely to specific successional stages
while others are found across multiple successional stages.
Chapter 25
* describe the different zones in a lentic system and seasonal patterns in a
temperate lake
- summer stratified: 3 layers (epi – warm and aerated, meta – thermocline, hypo – cold and
nutrient rich), nutrients stay on bottom because of temperature and density difference
- fall overturn: water cools, uniform density, wind stirs water making nutrients in bottom stir up
- winter: ice floats, warmer below (ice insulates lower part), ice would freeze whole pond and
crush/freeze orgs if ice didn’t float
- spring overturn: ice melts, uniform density, wind stirs water making nutrients in bottom stir up,
PHYTOPLANKTON BLOOM (more sunlight in Spring means more photosynthesis)
* compare the headwaters to the mouth of a lotic system
- Headwaters: Shaded by trees, energy from CPOM, shredders convert CPOM to FPOM, P/R<1,
temp lower, DO higher, Trout
- Mouth: Energy from FPOM, collectors gather FPOM, P/R<1 (turbid water), temp higher, DO
lower, Catfish and Carp.
Be able to interpret the results/graphs from the various studies we covered in the class
which would include the gazelle and wildebeest of the Serengeti, advantage of being
parasitized, female lizards that made resource-based and gene-based decision as to
which male to pair up with.
Serengeti
Showed that gazelle would graze where wildebeest had grazed earlier; grazing
was actually healthier for the community than letting the plants grow
Advantage of being parasitized
Botflies – parasites that kill baby birds
wasps/bees – presence means much less botflies
cowbird brood parasite
2 types:
Mimic: eggs look very similar to orpendola
Dumper: eggs don’t match
orpendola host
2 types:
Discriminator: toss eggs that do not match out of nest
Non-Discriminator: will not toss out eggs that do not match
Explanation: In places with wasps, discriminator birds are best because they get rid the
brood parasites and their children survive. In places without wasps, non-discriminator
birds are best because the brood parasites get hungry and eat the botfly larvae, saving
their nestmates
Lizards
-Females moved to improved areas and those in improved areas had heavier eggs that
hatched sooner, so it looks like they selected for resources. However, DNA tests
revealed that females mated with the males who originally had the better rock piles,
which means they seemed to select for genes. Conclusion: females select for resources
when looking for territory to live in, but selected for genes when looking for a mate.
Objectives for chapters that have not been covered by previous exams
Chapter 20
* Discuss island biogeography theory (distance and land size effects) using the
theoretical graphs and using data.
- The bigger the island, the grater the biodiversity and # species
-The closer an empty island is to a populated island, the more species will colonize
the island and the sooner the colonization will happen
* Relate the theory of island biogeography to conservation issues (size of land to
purchase or if only small fragments of land can be purchased, then issues of
closeness or connectedness of the fragments)
-You have to make tough calls sometimes? If you have to get fragments, make
corridors! But corridors are their own issue
* patch metapopulations – issues concerning a) distance between and size of
patches (probability of recolonization (rescue effect) and probability of
extinction), b) patch size and shape critical for some sp (interior & edge
species)
-a. you want bigger patches rather than small patches, and you want a smaller
distance between patches
-b. edge species like more edge (duh)
* understand the marine reserves and the Narcisse snake dens in Manitoba
examples
-Marine reserve: they work! But there was no control group
-Snake dens – can’t just conserve the den area, need the place where they travel
too
* be able to interpret graphs associated with why lyme disease rates have
increased due to forest fragmentation
-ticks that carry the disease are e, forest fragmentation makes more edges
Chapter 21
* Describe the concept of the ecosystem.
-Abiotic and biotic aspects together
* Define kcal and how we use it to measure energy content of biological materials.
- it’s 1000 calories, usually just called calories
* Relate the laws of thermodynamics to ecosystem production.
- energy can’t be created or destroyed
* Know and be able to work with the equations associated with ecological
production for plants (GPP=NPP+R) and animals (I-W=A=P=R).
- See ppt
* Discuss what factors affect primary production (precipitation and temperature).
-precipitation is major key to primary production (compare rainforest with desert)
-higher temp usually means higher pp
* Define a food chain and food web.
-food chain: trophic level to trophic level
-food web: all the possible food chains in an ecosystem
* Define trophic levels and different kinds of ecological pyramids.
-producers, consumers, decomposers
* Discuss the efficiency of energy transfer through the food chain (10% rule) and
apply the equations for energy flow [(GPP=NPP+R) and (I-W=A=P=R)] to the
Silver Springs example.
-see handout
* Be able to calculate the energy needs of a snake following the example used in
class.
- slide 20-21 of ppt
* Describe the marsh trophic cascade.
- Snails grazing has a negative effect on the Spartina. Predators have a
negative effect on snail populations. This causes predators to have an indirect
positive effect on the Spartina by reducing herbivory by snails.
chapter 24
* compare and contrast several ecosystems discussed in lecture (bolded items in
the biomes handout)
-see biomes handout
Biogeography
– know the names and the barriers between the different biogeographical regions
- Nearctic, Neotropical, Palearctic, Ethiopian, Oriental, Australian
- Ethiopian/Palearctic border: Sahara
- Oriental/Palearctic border: Himalayas
- Australian/Oriental border: waterways in Indonesia
- Neotropical/Nearctic border: between Mexican plateau and tropical
lowlands
- know the general latitudinal pattern with regard to species diversity
- Decrease of species richness with increase in latitude
