Geography 2

Geography
Define range
-Area over which a species is found
-Defined by maps: Dot(locations out in space where species are found; GPS), and choropleth(fills in dotted range)
-An abstraction, fills areas not always occupied.
-also determined by a scale.
Range size determination; Large vs. small
-Smaller more common than large.Suggests perhaps that there are fewer generalists than specialists(Smaller ranges)
-Large range species more common on local leve, small range have low densities on local level.
What are pandemic species?
Species found over a large range area.
Why are ranges more elliptical or rectangular than circular and square?
-temperature, water source, geographic features.
Why do predators have larger ranges than herbivores?
-less energy at higher trophic levels, physically larger.
Why are ranges for species at high elevation larger?
-less food resources RAPOPORT’S RULE(look up)
What are the different distributions based on latitudes?
-circumpolar(caribou), boreal(fur), temperate(sugar maple), tropical(spotted dolphin)
What is disjunct dispersal(distribution)
-Jump dispersal main cause
-not unified
-Climate disjunctions: changes in climate separates populations, i.e. climate cooling and drying during Ice Age(Magnolia found in E. America/S.E China), alligators in America and china,
Gorillas- Rwanda & congo republic, used to be more widespread, pinched off in middle through cooling, reducing rainforests.
allopatric speciation
-separate populations over time may evolve distinctly different characteristics. If the geographical barriers are later removed, members of the two populations may be unable to successfully mate with each other, at which point, the genetically isolated groups have emerged as different species
What are geological disjunctions?
-Tectonic activity causing disjunction.
What are Biogeographic Relicts, how do they occur, what are glacial relicts?
-species that had large range but have shrunk to narrow endemics.
-“Paleoendemics”
-become relicts due to narrowed range from climate change
-Glacial relicts: monterey pines/torrey pines, used to be widely dispersed along CA, likes cool climate/water, global warming (past 10,000yrs) has minimized sites.
-survive due to cool summer fog.
What are evolutionary relicts?
-survivors of formerly more widespread and diverse evolutionary lineages.
-ginko tree, cycades, magnolia
-SOME Relicts can be both evolutionary & climatic- Ca Coastal Redwood, Dawn Redwood(china)”living fossil”
How many species are identified on earth?
1.7 million, MANY more unidentified
-majority are insects, then plants, vertabretes are very small(2.7%)
what is species richness?
-Biodiversity but doesn’t describe species evenness or rarity.
-Area & species richness correlation- biodiversity increases with areas, biggest at ends(small gains and end gains)
-# of species per area not just total, more about density.
What are Global “Hot Spots”, what are some in US?
-areas of high species richness/diversity
-amazon, andes, tropical rainforest, SE Asia
-Lots of mountains, niches
-In USA: Appalachian: altitudinal diversity, meeting place of southern/northern type trees, HIGHEST PLANT DIVERSITY IN US
California: Highest animal diversity
Name some patterns in geographical patterns of Biodiversity.
-Global scale pattern: plant biodiversity greatest in tropics/low latitudes due to “Primary productivity”- high sunlight/rain
-Perhaps disturbance @ high latitudes- Ice ages, primary productivity is main theory.
Factors that increase biodiversity
-Physically diverse habitat with many niches,(rainforest canopies)
-Altitudinal diversity
-Resource rich environments: rich soils, water, etc.
-High diversity at 1 trophic level can stimulate high diversity in another. E.g. grasses that allow for different types of foods, specialization, etc.
-Moderate amount of disturbances- fire ecology
factors that reduce biodiversity
-extreme environments: polar, cold
-limitation of crucial resource: deserts, lack water
-environmental stress
-habitat fragmentation
-extreme amounts of disturbances
-introduction to exotic species.
what are the effects of habitat fragmentation?
-edge effect: boundary of 2 habitats, ecotones, can completely consume fragmented habitats that are small enough
Why conserve biodiversity?
Multiple perspectives of nature; different views and reasons
What are direct utilitarian values of CONSERVING biodiversity?
i.e. food, protecting wild grain species, or awaiting for new grain specie to survive.
-Utilitarian: food, protecting grain varieties
-Religion/Spiritual values
-Medicine and other compounds: Aspirin, taxol from canadian yew tree.
-Medical research: animals-tested, armadillo leprosy research.
-Aesthetic Values: enhance quality of life through beauty, like eco-tourism.
-Many indigenous peoples rely on local biodiversity for food, medicine, etc.
What are indirect utilitarian values
-Ecological service values: i.e. pollinators
-Ethical values(Bio-centrism): other species have moral right to exist independent of our need for them; we are global stewards.

-Evolutionary processes: more biodiversity more genetic material, healthier “raw material” for evolution.
Whats wrong with public policy on biodiversity?
Over focus on aesthetic landscapes instead of biodiversity landscape.
-dramatic landscapes of W. USA get preserved BUT East/South are much more biologically diverse.
-ACCEPTIONS: Everglades;( saved for high biodiversity), Charismatic Mega-fauna get attention/funding(What about the bacteria!?)
What is species-Based conservation? 2 kinds!
Directed toward one species; endangered species act!
-In situ conservation: focus on natural habitat of species, i.e. Northern Spotted owl sensitive to habitat
-Ex situ conservation: out of it’s environment, lab/cage/zoo maintain #s
What is Habitat-based conservation?
-hard to preserve one species alone so protect habitats instead, letting natural processes work.
-Nature conservancy buys up a lot of land for this.
What is environmental restoration?
-Go back and undo damage from humans, recreate habitats.
-LA river is in terrible condition, trying to revise
What is the traditional theory of island biogeography-species richness-Species turnover?(Another card)
-Author: MacArthur & Wilson
-Species richness coorelated w/ island size. Bigger island–>Bigger species richness; Also applied to lakes, mtns.
-Island proximity to mainland affects species richness. Closer=richer.
-assumption: species richness tend towards equilibrium AND rate of immigration – extinction.
-Rate of extinction determined by size of island: large=low, small=high.
-Rate of immigration determined by proximity to mainland: far= low, near=high.
What is species turnover?
Change in species composition not richness.
-Large island/far(low extinction few migrants)= low turnover, small/near=high
Examples that support traditional theory of island biogeography
-Krakatau island: formed in 1883 by volcano, in 1935 tropical forest established
Explain Alfred Wenegers theory
-Plate tectonics: Original theory is based off:
-fossil evidence
-shape of continents
-continents made of granite/ocean made of basalt.
-sub-tropic areas with signs of glaciation
-greenland moving west
What did Pangea split in 2?
-Laurasia: N. America, Europe, Asia
Gondwanaland: S. Asia, S. America, India, Australia, Antarctica
What is the newly discovered evidence of plate tectonics?
-More fossil evidence
-explains modern distribution of plants/animals.
-sonar/mapping sea floor found Mid-Oceanic Ridge.
-Age of Oceanic Crust(youg near ridge)
-Orientation of rock crystals(when cool, orient to magnetic fields)
When was the last ice age?
Pleistocene era
-3 ice sheets: laurentide, Greenland, Scandonavian
-Climate changes lead to sea level changes
Why do ice ages occur?
-Changes in orbit of earth relative to sun
-Milakovitch orbital theory of glaciations: There are warming/cooling periods, orbit around sun not constant.
-ECCENTRICITY: Orbits from cicular to oval.
-APHELION: Earth farthest from sun
-Obliquity: Axial tilt change, more tilt=more seasonality.
-Human induced climate change.
What is Orbital “eccentricity”, “Aphelion”, and “Obliquity”?
-Eccentricity: orbit goes from circular to oval determining timing of Aphelion- moment earth is farthest from sun
-obliquity: Axial tilt change: more tilt=more seasonality.
Animals most likely to go extinct first
-Complex: less likely to survive condition changes
-Large: more resources
-small population: local changes can wipe out entire population.
-Top of food chain: depend on prey
-specialists w/ narrow niche- can’t handle environmental change.
-slow rebirth
-Small range
-Low dispersal: cant shift to new location after environmental change.
What degines a biogeographic region/line?
-Region w/ genetic similarity of life
-Biogeographic lines: boundaries between regions, blurry, transition zones-Higher the taxonomic order= higher the biogeographic similarities(cosmopolitan= found in more than one place)
Simpson indec
estimates of similarities between different regions.
Highlights of nearctic & paleartic region
-many animals/plants shared
-HIGH DIVERSITY OF FLOWERING PLANTS
-Pleistocene extinction
Highlights of neotropic region
-3 marsupials
-MOST DIVERSE FLOWERING PLANTS! 137, 50 families.
-many shared w/ Africa/Australia
African Region
-MOST DIVERSE MAMMAL POPULATION
-Share lots of mammals w/ palearctic/oriental
-Share lots of plants with neotropic/australian but not animals
Oriental region
-endemic mammals: orangutans
-share plants w/ australia no animals.
Australian region
-most diverse, dominated by marsupials
-similar flowering plants to africa/neotropic
5 cases for plate tectonics/dispersal
-Angiosperm
-Marsupials/placentals
-Holarctic Region
-Panama Isthmus & Great America Exchnage
-Wallace’s Line
Angiosperm case for biogeographic regions
-Appear late jurssaic age, former laurasia/gondwanaland continents share similar species.
Marsupial & Placental case for bio-geographic regions
-meteor killed dinosaurs, allowed for new species to rise
-Marsupials evolved first in N. America, then disperse.
-Mammals evolve and out compete but never make it to Australia before ecut off.
Holarctice region case for biographic regions
-Holarctic= Neoarctic & Palearctic
-Very similar regions
-Land bridge(beringia) connected during ice age.
-similar latitudes-easier to migrate.
Panama Isthmus/Great American Exchange cae for bio geographical regions.
-climate changed opened passage but made it tropical
-“filtered” tropics made it hard to pass, create n.america/s.america difference.
-Always harder traveling N/S
Where did zacheys bro do his research? What was his job? What are fish weirs?
-Where:Tulilip Washington
-Job: protect treaty resources for future generations
-Fish weirs: enormous salmon suns allowed indians to be stationary
What did the Tulilip treaty decide?
-Tribes have right to 1/2 fish
-Tribes have say in environmental management
-Tribes have right to 1/2 shellfish
What caused salmon #s to decline
-overfishing
-dams:block upstream migration/caught in turbines coming downstream, the fish ladders allow for seals to predate.
-loss of habitat: ubranization/agriculutre/channelization runoffs
-hatcheries: release juvenile, genetic changes, disease
How to recover salmon?
-set goals: what were they before, how do we get there.
-Harvest:better fishing management, more hatcheries.
-Dams: fish ladders, removal, mitigation
-habitat: recovery/research
-PROBLEM: Population growth/develoment, politics, encforcement, pollution.
Why conserve biodiversity?
-Utilizing for people
-spiritual beliefs
-Ecological services
-Moral right
-Preserve genetic material, seeds, for more evolution into future.
Who came up with theory of biogeography and what are the main points?
-Macarthur & Wilson
-Size of island, proximity to mainland important for diversity
-not just for islands also mountains, forest fragments, pools, reserves.
What is species turnover? What is best setting?
-change in species composition not richness, best in middle away islands.
Rescue effect
close islands= less turnover rae because members of same species can migrat to save a struggling population.
LARGE RESERVE BETTER THAN SMALL BECAUSE…
-higher species richness
-less edge effect
-lower extinction
-target effect
-Several small bad because
-increase edge effect
-increase extinction
-isolation populations from one another, decrease rescue effect. unless they are in close proximity.
corridors between reserves good
-facilitate rescue effect
-connect populations.
wallaces line
-Biogeographic line separates indonesia from australia, sea level never declined far enough for species to cross over to australia.
-2 types of relict species
-Climatic: change of climate killed off most but a few left over, torrey/ monterey pine
-Evolutionary: geinko tree all thats left, smell like dog poo.
argument for several small nature reserves
-climate can change, natural disasters occur, need to divy up odds so they arent all wiped out at once.
-Species/area relationship non-linear , rises immediately with area then steadies out.
-habitat diversity, more different unique regions.
What regions are similar?
-S.America/Australia share angiosperm from when they were part of gondwanaland.
Small island effect.
-little difference in species richness among small islands.
minimum viable population size [MVPS]: # of individuals required for high probability of survival -> small islands at disadvantage

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