Transcript ap ecology - BiologyWithRizzo

Review:
•Species
•Population
•Community
•Ecosystem
•Biosphere
•Habitat
•Niche
•Population size (N)
•Population Density
•Dispersion
•Carrying capacity
•Limiting factors
-density-dependent (disease, predation, competition)
-density-independent (natural disaster, extreme climate
AGE STRUCTURE
SURVIVORSHIP CURVES
Type III: individuals die young;
organisms that produce free
swimming larvae.
Type I: survive to middle age
and the high mortality; humans.
Type II: length of survivorship is
random; likelihood of death is
equal; rodents, hydra.
K
K-selected species: population size remains relatively constant at the
carrying capacity (K). Humans; small number of large offspring that
require parental care until maturity.
r-selected species: rapid growth (exponential); produce many
offspring that are small, mature quickly, and require little if any
parental care and die quickly; opportunistic species such as grasses
and insects.
Interspecific competition: individuals of different species
compete for resources in the same area. Trees of different
species: one grows taller than the other species and more
successfully competes for sunlight and water; lions and cheetahs
compete for the same prey in the same area.
Intraspecific competition: individuals of the same species
compete for resources in the same area.
•Trees of the same species growing close together may compete
for resources
•Grasshoppers negatively affect others of their species by
affecting the resources in the same area; they don’t interact but
carry out exploitation competition
•Territorial species carry out interference competition by
preventing others of the same species from obtaining resources
in a given area.
Niche: how and organism “makes a living.” It is what an organism
does and when and where the organism does it.
•Fundamental niche: the full range of environmental conditions
and resources an organism can possibly occupy and use, especially
when limiting factors are absent in its habitat. (ideal and not
realized by organisms in nature) Like what you could do if you had
lots of money.
•Realized niche: The part of fundamental niche that an organism
occupies as a result of limiting factors present in its habitat. Like
what you would do if you had limited money.
•Competitive exclusion principle: (Gause) No two species can
occupy the same space and the same resources at the same time
successfully
•Resource partitioning: species occupy only slightly different
niches; five species of warbler living in a spruce tree.
Predators; Prey; and the sawtooth graph
SYMBIOTIC RELATIONSHIPS
•MUTUALISM: both species benefit (+/+)
•COMMENSALISM: one species benefits and the other is unaffected (+/0)
•PARASITISM: one species benefits and the other is harmed (+/-)
COEVOLUTION!
Perhaps the most recognized example of
coevolution involves pollinators and flowers.
The evolve in response to changes in one
another.
Coevolution: the evolution of one
species in response to new
adaptations that appear in another
species
Predator-Prey:
 Prey may inherit ability to better elude predator
 Predators may inherit ability to better capture prey
 Selection for these heritable traits leads to coevolution
Coevolution Continued
 Secondary compounds: toxic compounds in plants to
discourage herbivores (what’s “coevolution” about this?)
 Camouflage/cryptic coloration:
-color, pattern, shape, behavior that allows animals to
blend in with surroundings; benefits both predator and
prey
-Snowshoe hare (white in winter; brown in summer)
-Moth larvae colored to look like bird droppings
-strips are camouflage in forest, etc
-plants shaped and colored like surrounding rocks
(jeesh!)
 Warning coloration (aposematic): predators may
Coevolution Continued
 Mimicry: two or more species resemble
 Batesian: animal with no special defense mechanism
has similar coloration as animals who have special
defense mechanism and associated coloration (flies that
look like bees)
 Mullerian: bees, yellow jackets, wasps
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Several animals have same coloration associated with special
defense mechanisms
Succession
 Primary (no soil): life arising in areas that never
supported life (volcanic islands, lava flows, rock, sand)
rock -> lichen -> moss -> grass -> shrub -> trees ->
oak hickory forest
 Secondary (soil): life arises in areas that once supported
life but have experienced catastrophe (fire, flood, clearcutting, etc) grass -> shrub -> trees -> oak hickory
forest
 Primary Succession
 Pioneer species: first species to colonize a newly exposed habitat;
grasses, lichen, etc; r-selected species
 Primary succession
 1. Sand dunes on Lake Michigan (Indiana sand dunes of Clements)--can walk
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through the seral stages on a line perpendicular to the lake shore, going from
young to older and older seral stages.
a. Sand dunes on shore
b. Perennial grasses: stabilize and add organics
c. Annuals: further enrich soil and stabilize
d. Shrubs
e. Pines
f. Forest: first black oak and then beech and maple
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2. Atlantic coastal sand dune pattern is similar
a. Sea oats and beach grass: stabilize and add organics
b. Bayberry and beach plum and other shrubs: stabilize and catch sediments
c. Pines
d. Coastal forest
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3. Receding glaciers in Alaska (thin clay deposits)
a. Mat-forming mosses and sedges
b. Prostrate willows
c. Shrubby willows
d. Alder thicket
e. Spruce-hemlock forest
 Secondary Succession: reset of established community to an earlier stage by physical
or biotic process
 1. Clearcut forest
 a. Annuals -- Crabgrass to horseweed to ragweed
 b. Aster to broomsedge -- both of these are biennial
 c. Herbaceous perennials and shrubs
 d. Pines
 e. Hardwoods such as oak and maple
 2. Size of disturbance determines the amount of the reset and from where the colonists
come
 a. Forest
 1. Decrease number of limbs on trees--neighbors fill in
 2. Cut/blowdown tree in forest--saplings already present fill in
 3. Cut/blowdown number of trees in forest so a much larger gap--colonize by seeds and
usually the plants of the mature forest cannot live in such large open gaps due to
amount of sunlight. Colonists dependent on availability of recruits at the time of
disturbance (potential importance of seed bank), state of the habitat and the ability of
the recruit to live there
 b. Mussel bed in the rocky intertidal
 1. Remove a mussel--surrounding individuals close gap
 2. Remove number of contiguous individuals--gap will often grow due to wave forces
and such large gaps are colonized by water borne propagules
 Climax Community: after succession…has reached
steady state.
 Secondary Succession occurs more rapidly than
primary succession because it is the “reestablishment” of a climax community with existing
soil rather than the “formation” of a climax community
starting with only rock.
Biomes!
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Tropical Rainforest: (rife with epiphytes)
Savannas
Temperate grasslands
Temperate deciduous forests
Deserts
Taigas
Tundras: possesses characteristic permafrost
Fresh water biomes: ponds, lakes, streams, and rivers
Marine biomes: (estuaries, intertidal zones,
continental shelves, coral reefs, and pelagic ocean
Terms to Review!
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Primary producer
Primary consumer
Secondary consumer
Tertiary consumer
Decomposer
Food chain
Food web
Energy, biomass, and numbers pyramids
Flow of energy
Nutrient recycling
Eutrophication
Environment Impact Terms to
Review
 Greenhouse effect (global warming)
 Ozone depletion
 Acid rain
 Deforestation/loss of habitat and biodiversity
 Biomagnification (bioaccumulation)
 Introduced species (exotic species)
 Overexploitation
 Desertification
Material Cycles
 Know the cycles!
 Reservoirs
 Assimilation
 Release
 Water
 Carbon
 Nitrogen
 Phosphorus