ECO EXAM 2

• Birth rate
• mortality rate
• Immigration
• Emigration

• TIME..AT ONE TIME AT AGE OF DEATH
• AGE..FOLLOW COHORT THRU TIME

• AGE SPECIFIC IS BETTER.
• ALL ASSUME SEASONAL VARIATION!
• EXAMPLES:
• TREES AND RINGS.
• DEER AND LOWER JAW.
• FISH RINGS ON SCALES.

• NO.
• DEPENDS ON THE NUMBER YOU START WITH.

Q_X IS A RATE!

• l_X=n_X/n_O
• WHEN N_{x IS NUMBER ALIVE AT START.}

• 1. Type I – convex....K SELECTIVE. PARENTAL INVESTMENT
• 2. Type II – diagonal
• 3. Type III – concave...r SELECTIVE...TREES ARE TYPE 3 AS WELL.

• DENSITY (OF A UNIT AREA) =
• (BIRTH +IMMIGRATION) - (DEATH + EMIGRATION)
• OR....
• D = IN - OUT

3-4 AND 9-10

• The cycles appear to be the result
• of synergistic interactions between food availability and predation.

• a curve representing
• the number of individuals in a population that becomes steeper and steeper over
• time.
• Differential equation
• - assumes continuous reproduction
• DN = rN.
• Dt

natural increase or biotic potential {r}

FLAT

LINE WOULD GO DOWN.

• chaotic population dynamics.
• R >7 AT LEAST.

the tendency of simple, deterministic systems under some circumstances to exhibit complicated and effectively unpredictable dynamics.

when predator numbers respond to changes in prey numbers, i.e., prey go up, predator increase; prey go down, predator decrease.

• 1. Cryptic coloration
• 2. Aposematic coloration



• 3. Aggressive resemblance




• 4. Mimicry

• K
• PARENTIAL INVESTMENTS.
• ELEPHANTS.

r FAST GROWTH.

• a population that begins to grow exponentially, then begins to level off as it approaches the carrying capacity.
• Logistic population growth is represented by an S-shaped or sigmoidal curve.
• 

A distinction is made between a "strong Allee effect", where a population exhibits a "critical size or density

• the result of delayed feed-back in population density; can result in population
• fluctuations.

• the process by which environmental interactions determine the density of a population.
• HISTORICALLY, IT WAS VIEWED AS RESULTING IN EQUILIBRIUM (POPULATION) DYNAMICS.

• A factor or factors affecting population size whose intensity of action varies with density; that is, densities at time t influence densities at time t + x.
• PRESENT EFFECT FUTURE. THINK ABOUT THE K CAPACITY.
• GRIME TRIANGLE. COMPETITION FROM OTHERS.

• having influence on individuals in a population that does not vary with the degree of crowding.
• THINK GRIME'S TRIANGLE. STRESS, COMPETITION AND DISTURBANCE.
• DENSITY INDEPENANCE= STRESS OR DISTURBANCE. SOMETHING OUTSIDE OF THE POPULATION IS WORKING IT DOWN.
• NON EQUILIBRIUM DYNAMICS = DENSITY INDEPENDENCE.

DENSITY INDEPENANCE= STRESS OR DISTURBANCE. SOMETHING OUTSIDE OF THE POPULATION IS WORKING IT DOWN.

• INDEPENDENT.
• THINK HURRICANE COME ALONG, THAN A FIRE.
• POPULATION KEEPS ON GOING BUT NO INTERNAL COMPETITION.

• NO.
• NO EQUILIBRIUM POINT.
• BOTH BOUNCE ALL OVER THE CHART.

DEPENDANT.

TRUE

• 1. Fire
• 2. Floods
• 3. Ice-storms

• 1.Extrinsic – the population’s response to interaction with other members of the community.EXTERNAL
• 2. Intrinsic-the populations own response to its density.

• Extrinsic – the population’s response to interaction with other members of the community.
• Extrinsic factors:
• 1. Predation
• 2. Parasitism
• 3. Interspecific competition
• 4. Disease

• DENSITY DEPENDANT.
• DEPENDANT UPON THEIR FOOD.

• the populations own response to its density.
• Territoriality..COUGAR/MULE
• Reproductive inhibition... FEMALE MOUSE/HORMONES
• Dispersal...MOLES..TO HIGH..TAKE OFF.
• Stress..RABBITS..HORMONES..CORTICAL STEROIDS.
• Ideal free distribution...WOOD LOTS. DISTRIBUTION OF DENSITY.
• Intra-specific competition...FROM SPECIES OF SAME POPULATION.

• BOTH!
• DIFFERENT MECHANICS!
• 1ST PEAK IS DEPENDANT..POP EFFECTED SIZE.
• 2ND INDEPENDENT...WAS EXTERNAL, WEATHER.

• Intraspecific competition –competition between members of the same species for a limiting resource.
• 1.Exploitation – using up the resource before other individuals obtains access (scramble). GET IT 1ST.
• 2. Interference –involves direct interaction among competing individuals of the same species (contest). FIGHT.

• emigration.
• WILL STAY WITHIN RANGE.

• immigration.
• NOT REGULATED.
• CAN BECOME EXTINCT.

• spatially subdivided populations that are interconnected by occasional dispersal events.
• occasional dispersal events can result in recolonization of patches in which populations have gone extinct.

• STRONG SPECIES IS NOT EFFECT WHILST WEAKER SPECIES BENEFITS.
• BIRDS ON A WATER BUFFALO.
• SHARK AND THE RAMORAS.

a set of rules, including breadth of diet, by which organisms maximize food intake per unit of time or minimize the time required to meet their food requirements.

a measure of what the individual is trying to maximize; traditionally this was energy; more recently fitness.

movement towards a particular point.

subsequent movements influenced by previous movement.

BCWA = Biased Random Walk + Correlated Random Walk

• Degu
• Octodon degus

• The level at which an individual ceases to use a particular resource.
• Resources interspersed among a matrix.
• Based on optimal foraging theory.

• TRUE.
• SHOW HOW MUCH FOOD IS LEFT TO CONSUME IN EACH INSTANCE.
• 

• THE DEGUS FED MORE WHEN THE PREDATORS WERE TAKEN OUT.
• REMEMBER THAT THE GUD SHOW WHAT WAS LEFT AFTER FEEDING!!!

• ENTRINISTIC (IN)
• EXTRINSTIC (OUT)

• SCRAMBLE COMPETITION.
• WHO GETS IT FIRST.

• ELEVATED.
• LOWER NUMBER SHOWS WHAT'S LEFT AFTER FEEDING.

• Grazers – eat herbaceous plants such as grasses and forbs, e.g., bison and grasshoppers.

• Browsers – eat leaves and

• twigs of woody material, e.g., deer.

• Frugivory
• Seed predation
• Nectivores
• Leaf mining
• Roots
• Sap suckers..WOODPECKER AND APHIDES

• 1. significant reductions in density
• 2. altering growth forms
• 3. reductions in biomass
• 4. changes in interspecific competition.

• TRUE.
• ANIMAL DISPERSES THE SEEDS

• Morphological...THORNS
• Associational...GROW NEAR A THORN BUSH
• Chemical (secondary compounds)...POT OR ALCOHOL IN SEEDS.

Lotka-Volterra predator-prey model

change in predator numbers over the change in time in relation to changes in prey density over time.

2,4,8,16,32,64..

• ONE MIGHT NOT COVER THE COMPLETE CYCLE OF THE ORGANISM.
• SPRUCE BUDWORM. CAN'T DO A 10 YEAR CHART WHEN IT'S CYCLE IS 25.

• Numerical response –
• when predator numbers respond to changes in prey numbers, i.e., prey go up,
• predators increase; prey go down, predators decrease.
• Three types of functional responses:
• 1. Type I....ZOOPLANKTON
• 2. Type II....SEEDS...EAT FAST THEN LEVEL OFF
• 3. Type III...SEARCH IMAGE. IF RARE, LESS LIKELY TO EAT. BUT IF COMMON THEN BECOMES AVERAGE.

• 1. Type I....ZOOPLANKTON
• 2. Type II....SEEDS...EAT FAST THEN LEVEL OFF
• 3. Type III...SEARCH IMAGE. IF RARE, LESS LIKELY TO EAT. BUT IF COMMON THEN BECOMES AVERAGE.

.

• 1. Cryptic coloration
• 2. Aposematic coloration
• 3. Aggressive resemblance
• 4. Mimicry

is the resemblance of one organism to a not very closely related organism living in the same area.

• 1. Batesian mimicry – an edible mimic resembles a distasteful or poisonous model. e.g., viceroy – monarch mimics; fly – bee mimics; king snake – coral snake mimics.
• 2. Mullerian mimicry – when several poisonous or unpalatable species resemble one another.

• FROGS IN TROPICS.
• BEES/WASPS/FLY IN MIDWEST.

• 1. Batesian mimicry – an edible mimic resembles a distasteful or poisonous model. e.g., viceroy – monarch
• mimics; fly – bee mimics; king snake – coral snake mimics.

• the killing (and often eating) of ones siblings.
• ARCTIC RAPTERS.
• LAY EGGS AT DIFFERENT TIMES.
• FOOD.

• parents killing the young of another individual
• MALE LIONS.
• FEMALE MICE..HELP HELP FOOD SOURCE STRONG.

• NUDEABRINKS.
• 

Ectoparasite – parasites that live on their hosts, e.g., fleas and ticks.

Endoparasite – parasites that live in their hosts, e.g., viruses, blood flukes, and some tapeworms.

Microparasite – comparatively small parasites that generally multiply within their host, e.g., viruses, bacteria, and fungi

• Macroparasite – comparatively large parasites that generally do not multiply within the host; produce eggs or larvae that pass out of the host; e.g.,
• parasitic worms and arthropods.

Parasitoids – flies or wasps that live as parasites within the egg, larvae, or pupa of another insect, consuming its tissues; eventually they emerge and the host dies.

PARASITIC WASP INJECTS FLY WITH EGGS.

TRUE

RIVER FLY

LIECHMANS TYPE OF DISEASE.

SNAIL AND DUCK.

TICKS.

TRYPANAZOMA.

TRUE

where individuals of one species, the commensal, live off of another species, the host; the commensal benefits and the host suffers no negative or positive effects; e.g., epiphytic plants.

the transport of one animal by another.

organisms that obtain their energy from dead or dying tissue.

• Saprobism – organisms that obtain their energy from dead or dying tissue.
• vultures, condors, some hyenas, blow-flies, burying beetles, dermestid beetles, stinkhorn mushrooms.

• 1. CARRION.
• 2. DUNG.
• 3. DEAD WOODY MATERIAL

TRUE.

• 1. Resources may never or only rarely be in short supply. Consequently, competition is of relatively little importance.
• 2. Competition between two species may be mild enough that they can coexist.
• 3. Ghost of competition past: Competition may not be observed between two species, although sometime in the evolutionary past members of the two species were in competition.
• 4. Competition may result in competitive exclusion.

• A. The resource may nondepletable, rapidly renewable, or nonmonopolizable.
• B. Predators or parasites may depress prey to a level in which interspecific competition does not occur.
• C. Annual variability in seasons prevents populations from reaching carrying capacity.
• D. Disturbances, such as fires, floods, and ice-storms, prevent populations from reaching carrying capacity.

• CARABO (MAINE) COMPETITOR WITH DEER.
• CARABO DEAD, NOT DEER.
• PARASITE. BUT LOOKED LIKE DEER.
• ANOTHER
• LYNX, RABBIT AND HAIRS OF NOVA SCOTIA.

arising or occurring between species; "an interspecific hybrid".

:occurring within a species or involving members of one species

TRUE

TRUE.

an organism that at an earlier time was abundant in a large area but now occurs at only one or a few small areas

An area that has escaped ecological changes occurring elsewhere and so provides a suitable habitat for relict species.

• TRUE
• THINK GHOST COMPETITION.

• YES.
• MICE VS MOLE

dependent.

a coaction in which one species is harmed and the other is unaffected.

• Chemical inhibition of one organism by another. Generally used in reference to higher plants.
• TREES. WALNUTS. MARIGOLD.

• when two species have negligible effects on each other on an ecological time scale. Neutralism may evolve from competition.
• GHOST COMPETITION.

the coaction which both species benefit.

Lichens(algae and fungi) and herbivore / digestive microorganisms.

• fungi that are found in close association with the roots of vascular plants.
• Endomycorrhizae enter the cell.
• Ectomycorrhizae go between the cells.

KUDO AND BIRD IN AFRICA.

seed dispersal and pollination