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2011-10-19 23:45:04
biology geography

Test 2
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  1. Allelopathy
    Competition between plant species in which the chemical compounds released by one species inhibits the germination or growth of competing species
  2. Dominance vs Density
    • dominance
    • not how many, but how dominant they are
    • fire comes
    • 1,000 small, new ash trees
    • only have about 12 old hickory trees that survived the fire
    • those 12 are so big that they take all of the sunlight though
    • less amount, but more dominant

    • density
    • number based on what % of X you have in an area (100 oak trees per square mile)
  3. Euryphagous
    an organism that can consume a wide variety of different foods
  4. Stenophagus
    an organism that can only consume a narrow variety of different foods
  5. Ecotone
    the geographic boundary between two different adjacent communities


    • line inbetween grasses and praries
    • where does one end and the other begin?
  6. Biome
    very large areas of the earth's surface that have a similar climate and vegetation
  7. Life Zone
    elevational and latitudinal bands of similar climate and vegetation
  8. Superorganism Community Concept
    Clements' concept that the species in communities had evolved together over long periods of time and were highly dependent upon each other, much like the individual organs in an animal depend upon the functioning of all the other organs
  9. Competitive Exclusion Principle
    the theory that species with identical niches cannot exist in the same geographic region because one would eventually drive the other to extinction
  10. Keystone Species
    a species that due to its presence or absence can greatly change the productivity, species composition, or sepcies diversity of an ecosystem
  11. Optimal Foraging Theory
    the theory that predators evolve to focus their foraging activities upon prey species that provide the highest ratio of food energy relative to the energy required for foraging
  12. Lotka-Volterra Model
    a mathematical model that relates cyclic fluctuations in the size of predator and prey populations to the interaction between predators and prey themselves
  13. Surface Fire
    a fire that is restricted to the ground level and lower vegetation and does not rise into the tree canopy if trees are present
  14. Canopy Fire
    a fire that burns in the canopy cover of a forest
  15. Alpha Diversity
    the degree of difference between species found on different sites of the same habitat or community type
  16. Beta Diversity
    the degree of difference in the species composition between two different habitats or community types
  17. Dominance Type
    plant associations that are defined and descried on the basis of the one or several plant species that structurally dominate them
  18. Superposition
    idea in geology, geography, where things that are above something (in a layer of soil for example) are newer

    plate tectonics, the middle is newer than the outside; superposition
  19. Uniformitarianism
    • present is the key to the past
    • know the past, explain the present

    erosion happened this way now, it happened in the same way in the past, takes this long, so we can date the earth
  20. Environmental Gradient
    changes that occur in the environment that can change density, niche, and carrying capacity
  21. Density
    the number of individuals of a given species per unit of area
  22. Biomes

    Life Zones
    biomes are defined with latitude

    life zones are defined by elevation
  23. Niche
    the multidimensional resource space in which a species exists
  24. Fundamental Niche
    the niche space of a species if there was no competition with other species that decreases the range of resource conditions it could exist within
  25. Realized Niche
    the reduced niche space occupied by a species due to the impact of competition with other species
  26. Symbosis

    3 types
    the close association between two species that generally develops through coevolution. In many cases, the symbiotic association is obligatory for the survival of one or both species.

    • Mutualism
    • helps both
    • Commensalism
    • helps one, but doesnt hurt the other
    • Parasitism
    • helps one, hurts the other
  27. Primary Succession
    occurs when a previously lifeless environment is first colonized by plants and animals
  28. Secondary Succession
    occurs when an existing ecosystem recovers from a disturbance such as fire or flood
  29. Continental Drift
    a widely accepted theory that the geologic plates on which the continents lie have shifted their relative geographic positions very significantly over geologic time
  30. Plate Tectonics
    the modern theory of how continental drift occurs due to the movement of the mantle and outflows of magma that cause movement of the overlying crust
  31. Describe a typical geographic range of species (in terms of density of individuals) that generally results from the interaction of various limiting factors
    Herbivores will have to eat a large variety of plants due to the low amounts of nutrients in grass. Because of this, they have a much smaller range due to the trophic level biomass. Since they are lower in the trophic level, they need much less under them to support them.

    Carnivores, if ectothermic, will have to make sure their environment is suitable for decomp of what they are eating. If they are endothermic, they will have a much larger range than ecto. Ecto will still have a larger range than a herbivore though. They have the much larger range due to the trophic level biomass and since they are much higher up in the trophic pyramid they have much more under them to support them.

    A good example of an animal that has wide distribution becuase of low-limiting factors are us humans. Not only are we eurythermic (able to withstand large temp variety), but we are also capable of being euryphagous (able to eat a wide variety). Beause of this, we have a large distribution. On the other hand, many species of Eucalypts, which are endemic to Australia, will have many more limitations, causing a much smaller distribution.


    • an animal may be physiologically able to live in all areas
    • how many limiting factors will decide where it lives though
    • your realized niche is a subset of your physiological niche
    • numerous factors that actually change over time will decide where a species lives
  32. Discuss the role of predation on the distribution of species

    Relationship of Species/Prey
    If a predator depends on only one particular species for its prey (stenophagous), the geographic distribution of the predator is necessarily limited to the geographic distribution of the prey species. A perfect example of this is the monarch butterfly and the milkweed. I wouldnt call the monarch a predator, but the same principle applies. This is a poor strategy for many species, but the number one reason for doing this is the cost-benifit of food eaten to energy spent retreiving that food (optimal foraging theory). Another reason for doing so is that some plants give off toxins that only the animal of that plant can eat witout dying.

    On the other hand, if a predator is euryphagous, they will have a much larger range and distribution. This is a much better adaptive strategy due to the fact that if one prey species goes extinct, the animal can survive off another.

    In general, carnivores display a much lower degree of stenophagy than do herbivores.
  33. Discuss the role of predation on the distribution of species

    Role of predator
    According to the Lotka-Volterra model, the predator is much less importatnt than the prey.

    • steno predators will be tightly linked with the prey population
    • if one goes down in pop, the other one will go down in pop and vice/versa


    • Lynx feeds primarily on the hare
    • lynx has a higher range, but the hare falls exactly into the distribution of the lynx
    • some argue that as a consequence, the abundance is effected as well
    • less for the hare to eat, less of them, less for the lynx to eat
    • vice/versa
    • if the lynx goes extinct, the hare will spike, then crash due to Malthusian

    • Keystone Species
    • species that is so important, if you remove it, the entire ecosystem will be dramatically changed
    • loss is more significant than any other species in the ecosystem
    • if no key predator, huge pop spike, then the complete elimination of those who can't compete
    • makes the lotca volterra look wrong
    • lotca volterra has more to do with the prey than the predator
  34. How does competition affect species distribution?


    • competing within the same species
    • competition is more intense than inter

    • Direct
    • same species (different genus) eating the same thing
    • the high end of one species will overlap the low end of another species
    • the overlapping is where the competition happens
    • o.k. if there is enough resources (overlapping occurs)
    • vice/versa
    • if vice versa happens, evolution and adaptation occurs, eventually spatially separating themselves from one another


    when certain types of algea are produced alone, they thrive. when produced together, one can cause the other to go extinct
  35. How does competition affect species distribution?


    two or more species competiting

    • Indirectly
    • not closely related species eating the same thing
    • a way of getting around this is spatial separation
    • spread niches apart, spreading yourself out over time


    • swallows eating insects high in the air
    • thrashers middle
    • woodpecker low middle
    • blackbird low


    • warbles species (different genus) eating at different levels of a tree
    • cape may at top
    • black throated in the middle
    • yellow rumped at the bottom
    • "spatially partitioning" the prey on the tree
  36. 3 types of Symbiosis
    • 1) Parasitic
    • 2) Mutualism
    • 3) Communalism
  37. Parasitic
    • benefits one, effects the other badly
    • benefit at the expense of the other
    • cant live on their own, need other for nutrients, so they dont kill the host
    • this type of control determines the geographic distribution of one or both of the species involved


    ticks, fleas, lice, mites
  38. Mutualism
    • benefits both
    • hurts neither


    • moths in the south-west feed on yuccas
    • yucca depends on the moth to transfer their pollen
  39. Communalism
    one benefits, doesn't effect the other badly/good


    • clownfish
    • overlapping range, but not tight at all
  40. Clements Model
    • Succession
    • in bio, plant communities go through successor cycles
    • different biomes succeed one another over time
    • grasses, succeeded by shrubs, then pines, then forestry
    • different stages are called seres
    • most recent sere out competes the previous
    • primary being from day one
    • secondary is if a hurricane come in and destroys the more recent sere, it will start up again at that level
    • until it hits the climax again, or until it gets creamed again, and starts all over again
    • 3 concepts
    • 1) successional seres
    • 2) each sere creates soil conditions that helps out the next sere
    • 3) end in the Climax Community
    • when you get to the climax (forests) that was the end game to clements
    • the entire process is a "super organism" with everything being "connected"

    • Whittaker
    • individual species behave independently inside the ecosystem
    • as you go up from desert to tundra to grassland to savanah to tropical, you get higher biome productivity

    Some parts wrong, some right
  41. Rights/Wrongs of Clements Model
    • RIGHT
    • stages are more complex in the higher regions (more species)
    • since it has high biodiversity, change is o.k. and can be overcome easily
    • as you go up in seres, it actually becomes more stable/more productive and more nutrient retentive of an environment
    • WRONG
    • climax is whats wrong
    • in his mind, disturbance is bad


    • many different pathways to become a full fledged forest
    • not always a straight line going from one to the next perfect ally
    • competition
    • instead of facilitating(making it better), they actually make it worse
    • randomness
    • cycle is going around fine, hurricane come through, takes it back a couple of stages
    • to clements, it would just go back to normal
    • when a place gets whipped out, there are still other trees around the place that didn't get knocked out
    • these trees will drop their seeds, and create a late stage right away, or a bird takes a dump, or grasses that still have live seeds will grow…random
    • you can end up having different species dominating the habitat depending on the randomness of the ecosystem
    • in other words, it can happen in the way clements said, but it can also happen in different ways


    • Patch Dynamics
    • value of having a patchy environment instead of having a homogenous community
    • numerous seres, changing at different times spatially
    • some change in the type of disturbance
    • severity of the disturbance
    • intensity of the disturbance
    • size of the disturbance
    • regrowth time after the disturbance
    • if burn happens often, the stages will never be able to get very far
    • if burn happens less often, the stages will recover and move on quicker
  42. Tolerance Model
    In many instances, species of both early and late seral stages are estabilished very quickly following disturbance. The plants that dominate the early successional period simply are those that grow the fastest. The slower growing plants that dominate the later stages eventually displace the early dominants. All of the species can tolerate the early successional environments, but as the succession progresses, some of the early dominants can no longer tolerate the increased competition for light and moisture.
  43. Inhibition Model
    In some ecosystems, particularry following small disturbances, it is very difficult to predict which species will invade and eventually dominate a site. It appears that proximty to seed sources and chance factors related to seed dispersal play a major role in determining which species the site. Once the site is occupied, the presence of the early invaders inhibits establishment of other species.
  44. Random Model
    Succession can be typified simply as the random arrival of species at a disturbed site. This random model assumes that there is no facilitation or inhibition.
  45. FIRE!!!!
    • are all fires bad?
    • no, it can replenish the soils, and some species have actually adapted to the fires lol
    • the giant redwood actually needs fire to reproduce
    • really thick bark creates a large barrier
    • they get "fire scars" but it doesn't kill em
    • shed their lower branches to stop it from catching and spreading
    • serotinous cones that need heat before opening
    • cones open and shed their seeds, comp is gone from the fire, soils good from decomp, and yeah, good growing for redwoods
    • grasslands would not exist w/o the existence of periodic burns
    • forrest/shrubs would outcompete them and take over
    • grass is adapted to fire, and survives only due to the fire

    how so adapted?

    • grass
    • seeds in the soil for annuals
    • root mass of perennials
    • 60% of plants mass is in the roots
    • shrubs
    • some are actually designed for fire
    • crown spouters
    • burn the top, but not the bottom, comes back right after the fire
    • good since it kills everything else
    • trees
    • high branches
    • thick bark
    • some need fire for germination (open their seeds)


    • virtually no area that hasn't burned
    • burning at different times at different places
    • so you get different levels of biodiversity all over the place
    • as long as you have uneven burns (preferably at different times), you get an overall increase of biodiversity
  46. What does it take for fire to happen/driving factors?
    • Lightning
    • causes the spark
    • most come from this
    • Fuel
    • biomass decomp
    • lack of humidity
    • Wind


    • Almost all ecosystems have burns
    • the question is the frequency…prarries happen every couple years, tundra happens every 600-1000 years
  47. WIND!!!!
    • Huricane Andrew
    • individual tree fall caused a turn over in 80% of the trees every 100 years
    • in a hurricane prone place, the tree fall was more of a disturbance than the hurricane itself
  48. FLOODS!!!!!
    • river flooding overtops the banks and drops off sediment
    • causes patchiness due to the different amounts of water flooding at different parts of the river


    • bald cypress live in a flood filled area
    • if it drops it seeds in the water, won't they rot?
    • seeds don't have snorkels lol
    • seeds have a coating
    • current of the water pushes the seeds to the riparian
    • not much wind though, so it waits until a flood
    • water floods over the land, water recedes, seed stays and grows
  49. How are biomes defined/identified?

    How are diversity, dominance, frequency, eveness used
    • EVE
    • the degree to which the number of individual organisms are evenly divided between the different species of the community

    • Ecological classification
    • function (deciduous,boreal)
    • complex biodiversity
    • productivity (amount of carbohydrates being produced)


    • 100 species all with:
    • = richness
    • = species type
    • = individuals

    • 900 species a
    • 100 species b
    • high domination

    • 100 species all with:
    • = richness
    • = species type
    • = individuals

    • 10 of each species
    • no domination

    • how you classify the characteristic matters greatly
    • one might make it seem similar
    • one might make it seem very different

    • = richness
    • = species type
    • = individuals

    • all being equal makes it seem similar
    • domination type might make it seem different


    • dominance
    • not how many, but how dominant they are
    • fire comes
    • 1,000 small, new ash trees
    • only have about 12 old hickory trees left after the fire
    • those 12 are so big that they take all of the sunlight though
    • less amount, but more dominant

    • density
    • number based on what % of X you have in an area (100 oak trees per square mile)
  50. Milankovitch's hypothesis of the earth's orbital parameters and ice ages
    • calculated the changes in the earths orbit
    • it changes!!!!!!
    • how much of the earths orbit changes with gravitational pull
    • calculates the tilt changing as well
    • calculates the equinoxes/solstices
    • change the orbit/tilt you change the solar radiation of the planet
    • does it latitudinally
    • from this model, he was able to predict when the ice ages came, and will it will come again

    • Orbit
    • varies over time from eccentric to sphere
    • takes 100,000 years
    • eccentric takes 50,000
    • sphere takes 50,000

    • Tilt
    • size is not constant
    • 23.5
    • varies from 21-24 over time
    • when its at 21, more heat is being concentrated on a smaller part, making other parts cooler
    • changes every 42,000 years

    • Equinox/Solstices
    • changes every 23,000 years
    • Fall equinox is in Sept
    • 5,000 years later, it will be in December
    • 5,000 years later, it will be in March
    • 5,000 years later, it will be in June
    • 5,000 years later, it will be in Sept

    When the Orbit, Tilt, Equinox/Solstices match up, you get either a warming or a cooling period; dependent on whether or not they match up high or low

    squiggly line thing ;)
  51. What causes a glaciers?

    Eccentric or Sphere?
    • trick question thingy...
    • Eccentric being the long, rectangulary thingy...
    • Sphere being the short, squarey thingy...
    • Sphere is the right answer.

    Eccentric is too cold, not enough moisture in the air, ice forms, but not enough and the heat side melts it all off
  52. Plate Tectonics and Continental Drift Proof

    How it works
    Plate Tectonics

    • 1)species (fossils) living in the same area
    • living nowhere except south america and africa
    • 2) glacial scarring
    • glaciers evidence of existing in places where latidudly could not exist
    • move them together, and they are at a latitude where they could exist
    • 3)area along the ridges/mountains (on the ocean floor) are the youngest
    • get older as you move towards the continents
    • 4) ocean floor mountains taller than any land mountain
    • 5) ocean floor trenches are deeper than the reverse of any land mountain
    • 6) pattern to the cycling

    Continental Drift

    How its moving

    • Push/Pull
    • push
    • as magma makes up to the surface, it cools as it hits the ocean floor
    • new magma comes up, and pushes the old magma out of the way, moving the continents
    • pull
    • acts as a convection cell under the earth
    • not all of the magma makes it up to the ocean floor
    • moves in a circle back down into the earths core
    • the way going in the circle is what is pulling the earth apart
  53. Figure 4.1
    • monarchs only feed on milkweed
    • stenophagus
    • good adapt since they are pretty toxic, and not too many insects eat the milkweed due to this
    • then they eat the toxins, making them uneatable by predators
    • vice roy (looks like the monarch) mimics the monarch to not get eaten
    • rules out competition of the milkweed as well, since the monarch is the only one that can eat it
  54. 4.5
    • in the absence of comp, they are equally capable of inhabiting all areas (Organ/Ruby/Pilot/Magdalena
    • Mountains)
    • introduce a competitor, and they partition the area out (Snake/Taylor Mountains)
    • dorsal is in the low due to it being more aggressive, more defending, find an easier place to defend, trees are more patchy
  55. 5.9
    im screwed...
  56. 5.13
    • how can the bald cypress live in a flood filled area
    • if it drops it seeds in the water, won't they rot
    • seeds don't have snorkels lol
    • seeds have a coating
    • current of the water pushes the seeds to the riparian
    • not much wind though, so it waits until a flood
    • water floods over the land, water recedes, seed stays, and grows


    • great adapt to water
    • adults survive in water
    • seeds fall in high flood events
    • water receeds
    • seeds fall to the ground

    where the fall stops is the fall line