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160 Cards in this Set
- Front
- Back
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What Is Ecology?
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Ecology is the science that deals with all kinds of biological interactions.
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What is environment?
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The term “environment,” as used by ecologists, includes both abiotic (physical and chemical) factors and biotic factors (all other organisms living in an area).
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Ecological Systems
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Organism: survival and
reproduction, the unit of natural selection Population: population dynamics; the unit of evolution Community: Interaction among populations Ecosystem: energy flux and cycling of nutrients Biosphere: Global processes |
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Niche
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the role of the
organism in the ecological system, also N-dimensional hypervolume, in which each dimension describes one of a species’ requirements. |
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Habitat
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the place, or physical setting in
which an organism lives |
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Fundamental niche
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is a listing of an organism’s idealized requirements
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realized niche
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a shrunken version of an organisms'
fundamental niche.The reason that the realized niche is shrunken usually has to do with the presence of other species, whose niche requirements might be overlapping. |
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species richness
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the total number of species in a given area
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Eveness
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uniformity in abundance of species
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diversity indices
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measures where the contribution of each
species is weighted against its relative abundance |
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relative abundance
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the proportion of the total number of
individuals in a community that belong to a particular species (pi = proportion of each species in the total sample of individuals) |
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Simpson’s Index
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considered a dominance index because it weights
towards the abundance of the most common species. It measures the probability two individuals randomly selected from a sample will belong to the same category D = 1/? pi^2 |
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Shannon Index
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The index measures the uncertainty of a category in a particular set
It is a measure of evenness Assumptions: All species represented Sample randomized (equal probability of being selected in the sample) H = - ? (pi * loge pi ) |
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Scale
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the dimension in space or time over which
variation is perceived |
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dynamic steady state
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When inputs and outputs are balanced
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Nile Perch Example
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-Introduced as food in 1950’s
-Became invasive and ate all the other fish in Lake Victoria -Drove smaller species (100’s) of fish to extinction and reduced its own food supply -Oily flesh preserved by smoking…led to severe deforestation of local forests |
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Sea Otter Example
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Sea otters eat urchins, keep urchins from destroying kelp beds, eat shellfish, eaten by orcas and humans, humans eat shellfish. Keystone species.
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resource partitioning
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The division of resources such that a few dominant species exploit most of the available resources while other species divide the remainder; helps explain why a few species are abundant in a community while others are represented by only a few individuals.
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What advances changed Biogeography?
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- Continental drift
- Phylogenetic taxonomy - Theory of island biogeography |
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Periodic cycles in climate that follow astronomical cycles:
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-Periodic change is patterns of change in temperature and precipitation.
-the rotation of the earth on its axis causes daily periodicity - the revolution of the moon around the earth causes cycles in the amplitude of the tides - the revolution of the earth around the sun brings seasonal change |
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cells of air circulation
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created by differential warming of the earth's surface
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Global Circulation
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In addition to the
development of “cells” of moving air, the rotational force of the earth directs the movement of the winds, resulting in “Westerlies” in the Mid-Latitudes and “Trade winds” in the Tropical latitudes |
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Intertropical
Convergence Zone (ITCZ) |
Warm moist air rises in the
tropics, which results in abundant rainfall |
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Subtropical High Pressure
Belts |
Cool dry air descends to the
surface at subtropical latitudes, creating desert conditions |
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Upwelling
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any vertical movement of water.
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Global Oceanic Circulation
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Variation in marine conditions is caused by winds, which propel the major surface currents of the ocean. Ocean currents redistribute heat and moisture.
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Seasonal variation in climate
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Seasonal variation in climate is caused by the movement
of the sun’s zenith. |
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El Niño- Southern Oscillation (ENSO)
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El Niño is a disruption of the oceanatmosphere
system in the Tropical Pacific having important consequences for weather and climate around the globe. Climate sustains irregular fluctuations |
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Solstice
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Northern or Southern Hemisphere tilted towards sun (June, Northern)
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Equinox
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Equator faces sun directly, neither pole tilts, all regions on Earth experience 12 hours of daylight and 12 hours of darkness.
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Tropics
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23.5 degrees above and below equator. Above=Tropic of Cancer. Below=Tropic of Capricorn.
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Periodic cycles (and examples) cells of air circulation
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Hadley- central zone. central upper=northeasterly trades, aka tropic winds, central south- southeasterly trades
Midlatitude- between polar and hadley, "westerlies", Polar |
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La Nina
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El Niño is a disruption of the oceanatmosphere
system in the Tropical Atlantic having important consequences for weather and climate around the globe. Climate sustains irregular fluctuations. Pressure flip flops, water go e-w instead of w-e. |
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Rainshadow
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Dry air descdends, absorbing moisture, creating "rain shadow." Results in desert, forms after mountainous ranges where alot of snow dump happens (Sierra Nevadas). Snow dump/rain one side, not other (rainshadow).
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Adiabatic cooling
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The decrease in air temperature with increase in elevation (6-10C per 1000m)
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What is climate?
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• The climate of a region is the average of the atmospheric conditions found there over time.
• Weather is the short-term state of those conditions. • Climate is what you expect; weather is what you get. |
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Whittaker's Biomes
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Define by vegetation structure, described as function of temperature and precipitation.
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Biome
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Terrestrial environment defined by the growth forms of its plants. Biome boundaries can be abrupt (ocean to land) or diffuse.
Different Biomes: Tropical Forest, Savanna, Desert, Chaparral, Temperate Grassland, Temperate Broadleaf Forest, Coniferous Forest, Tundra, High Mountains, Polar Ice. |
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abiotic factors that affect organisms
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the non-living components of the environment, such as air, rocks, soil, temperature, water, peat, and plant litter
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Tundra
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Arctic and at high elevations. Vegetation is low-growing perennials. Arctic tundra is underlain by permafrost. Soils can be wet because of poor drainage. Animals migrate or go dormant for much of
the year. |
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Boreal/Temperate Evergreen Forest
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Long, cold winters; short summers.Dominated by evergreens in the Northern
Hemisphere: can start photosynthesis quickly in the short growing season. Have only a few tree species. Dominant mammals, (e.g., moose and hares, eat leaves). |
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Temperate Deciduous Forest
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Precipitation is distributed evenly, but temperatures fluctuate dramatically.Forests dominated by deciduous trees that lose leaves during the cold season. Temperate forests with the most species were not covered by glaciers during the Pleistocene.
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Temperate Grasslands
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Dry much of the year; hot summers and
cold winters. Much of this biome has been converted to agriculture. Rich in species; grasses, sedges, and forbs. Plants are adapted to grazing and fire. |
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Cold Desert
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In continental interiors and rain shadows.
Dominated by few species: low-lying shrubs. Plant growth concentrated in spring. Plants produce lots of seed that supports seed-eating birds and rodents. |
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Hot Desert
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At 30° north and south. More species and
structurally diverse vegetation than cold deserts. Succulents are common. Many annuals grow after a rainfall. Pollination and fruit dispersal by animals. |
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Meditteranean (Chaparral)
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On western sides of continents with cool
ocean currents offshore. Winters are cool and wet, summers warm and dry. Adapted to fire. Shrubs and low trees with tough, evergreen leaves. Annuals abundant, supports lots of rodents. |
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Savanna (Thorn Forest)
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On equatorial sides of hot deserts. Rainfall
may be heavy in summer. Small trees may drop leaves in dry winter. Acacia are common. Savannas: grasslands with scattered trees; supports large grazing and browsing mammals and large predators. |
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Tropical Deciduous Forest
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Most trees lose leaves during the dry
season. Many flower while they are leafless. Most have been cleared for agriculture and cattle grazing. |
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Tropical Evergreen Forest
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Equatorial regions with high rainfall.
Highest species richness of all biomes. Up to 500 tree species per km2. Also highest overall productivity. Most nutrients are tied up in vegetation; soils are poor. |
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Alfred Russel Wallace
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Established the foundations of biogeography, developed basic concepts/tenets of the field.
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Biogeography
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The study of patterns of distributions of populations, species, and communities. Geologic history of regions=very important to kinds of organisms found there.
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Biogeographic Regions
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Divided based on taxonomic composition. Boudaries are where species composition changes dramatically over short distances.
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Barriers to dispersal
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separate biogeographic regions (sometimes). Include mountains, oceans, etc.
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Different Biogeographic Regions
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Nearctic- N. America up
Neotropical-Central America down to half of South America Antarctic- Southern half of South America, Southern tip of Africa, New Zealand. Ethiopian- All save the top of Africa. Palearctic- Europe, Asia, N. Africa. Oriental- India, Tibet, Laos, southern China, Indonesia Australasian- Australia, part of Indonesia |
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Wallace's Line
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The line established by Wallace as a boundary between the Oriental and the Australiasian biogeographic regions
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endemic
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found only within that area
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What advances changed Biogeography?
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- Continental drift
- Phylogenetic taxonomy - Theory of island biogeography |
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Continental Drift
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Earth's crust floats, continents will therefore move.
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Alfred Wegner, evidence for continental drift
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1) Geometric fit of the coastlines of continents on opposite sides of the Atlantic Ocean.
2) Alignment of geologic features on opposite sides of the Atlantic Ocean. PROBLEMS: too many assumptions, factual errors, needed more evidence to test the model, lacked a plausible mechanism. |
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Pangaea
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280 million years ago, single supercontient.
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More evidence for continental drift
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1. Marine Geology Evidence
2. Stratigraphic Evidence 3. Paleoclimate Evidence 4. Paleontological Evidence 5. Paleomagnetism Evidence |
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Theory of Plate Tectonics,
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explains the
origins and destruction of the earth’s plates as well as their lateral movement or drift. |
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Marine Geology
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Mid Ocean ridges mark sea floor spreading, plates are moving apart
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Stratigraphic Evidence
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Mtns, Ocean Ridges, Rocks with same strata found in S. America and Africa
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Paleoclimate Evidence
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Glacial till (rocks left behind glacial movement) show deposits over pangaea.
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Paleontological Evidence
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Anomalies in fossil record resolved when viewed in the context of continental drift.
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Paleomagnetism Evidence
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Magma forms rocks, rocks have iron oxide particles that magnetize as they cool, capturing polarity of Earth. (micro magnets capturing polarity of Earth's field). Field occasionally reverses direction, recorded in rocks.
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area phylogenies
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phylogenetics applied to biogeographical questions.
trees transformed into area phylog... by replacing taxa names by place where taxa live(d) |
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Vicariance
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appearance of a physical barrier that splits range of species
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Dispersal
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Organisms cross an existing barrier and establish a population
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Discontinuous Ranges
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Areas where speices don't interact
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biotic interchange
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When land masses come together, two different biotas
can merge |
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Altruism
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E. Altruism: behavior that costs the actor but benefits a recipient
F. Altruism promotes the spread of alleles through relatives rather than through self |
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Behavioral Ecology
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A. Behavioral ecology develops and tests hypotheses about the evolution of behaviors in natural environments
B. Features of the environment have evolutionary effects on behavior C. Behavior is everything an animal does and how it does them. D. Behavior comes from genes and the environment. |
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Ethology
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NEED
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Environmental Effects
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NEED
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Fixed Action Pattern
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1. Fixed action patterns are behaviors that reliably appear at a particular stage, e.g. feeding response in newborn garter snakes to specific chemical cue
2. Instinctive behavioral sequence triggered by a sign stimulus, that is indivisible and runs to completion. |
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Imprinting
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e.g. identification with parent, song acquisition in white-crowned sparrows. Different from other learning by a "sensitive period" where behavior is learned.
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Innate
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Genetically Controlled behaviors. Graylag geese pull eggs back to themselves even if there is no initial sign stimulus (eg, the egg). Also: infants grasping, trying to stop yawning halfway through.
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Instinct
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NEED
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Kin selection
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is a generalization of natural selection
1. alleles for helping relatives can spread, because individuals within a kin group share alleles Natural selection tends to favor altruism because it enhances the reproductive fitness of relatives. |
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Learning
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Some behaviors can be continually reshaped throughout life; flexible learning
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Optimality Analysis: Optimal Foraging Theory
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Does an animal look for high quality or low quality food? Compromise between energy spent searching and energy/nutrition gained.
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Releaser
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NEED
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Migration
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also under genetic control, but much more complex than taxis or kinesis.
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Taxis
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Oriented movement toward (positive taxis) or away (negative taxis) from some stimulus. Eg, trout show positive current taxis (food comes from there, you don't get swept away).
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Kinesis
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A directed movement; a change in the rate of activity in response to an environmental condition.
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Pheremone: sexual and nonsexual contact
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Chemical communication. Non sexual- marking territory. Sexual-m following pheremones of f. Expect chem signals from animals that are widely dispersed, live in dense vegetation, have no mechanism for making sound.
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Lorenz, Tinbergen, and Von Frisch
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NEED
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Tinbergen's 4 questions
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1. What is the mechanical basis of the behavior? (chemical, anatomical, physical) (HOW)
2. How does development of the animal influence the behavior? (HOW) 3. What is the evolutionary history of the behavior? (WHY) 4. How does behavior contribute to the survival and reproduction? (WHY) |
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Monogamous
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Part of a mating system. One male one female. Can last one season, one year, lifetime, etc.
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Polygamous
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individual of one sex mates with multiple partners of another. Part of a mating system. Polygyny- Multiple F to one M. Polyandry- Multiple M to one F.
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Parental Investment
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Investment for males cheap, expensive for females, so females choosy.
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Tit for Tat Strategy
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individuals treat each other the same way from the last time they were treated when the last met. Ie, bats that don't share blood don't get blood when they need it.
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What factors will influence whether a behavior ends up being innate or learned
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Limited flexibility tends to be favored evolutionarily when mistakes are costly, and/or there is no opportunity to learn
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Phenotype
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the product of genotype interacting with environment
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Behavior
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B. Behaviors, like physiological and morphological features, are subject to both genetic effects and environmental effects
C. Behavior is influenced by genetic factors D. Behavior is influenced by environmental factors |
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Proximate question
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"How" Question, eg, How does a bee find its way back to the hive?
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Ultimate Questions
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"Why" Questions, eg. why did natural selection favor this behavior and not another alternate one?
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Interspecific interactions which are Negative/Positive
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Interaction is beneficial to one species and detrimental to the other
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Predation and Parasitism
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Predators catch individuals, consume them, remove them from prey population
Parasites- consume parts of host. Can be disease (internal/external) or may negatively affect the host but does not directly remove it from the population |
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Parasitoids
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consume the living tissues of their hosts, eventually killing them. combine traits of parasites and predators
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Herbivores
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eat whole plants or parts of plants.
Grazers- eat grasses/herbaceous vegetation browsers- eat woody vegetation |
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Detritivores
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Consume dead organic material, wastes of other species. no direct affect on pops that produce these resources. Recycle nutrients of ecosystems.
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Predators have adaptations for exploiting their prey.
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can vary in size relative to prey. prey are rarely much larger than their predators. extreme example: baleen whale eating krill. cooperative hunters are exception- take prey substantially larger than themselves.
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Carnivores
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well developed canines, knifelike premolars to secure/cut prey.
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Other predator adaptations
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-grasping/tearing functions
-digestive systems reflect diet |
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Prey mechanisms
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-Escape mechanisms
-Predator detection -plants can have thorns and defensive chemicals that dissuade herbivores. |
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Fixed Action Pattern
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Instinctive behavioral sequence triggered by a sign stimulus that is indivisible and runs to completion
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Habituation
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Loss of responsiveness to stimuli that convey little information
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Spatial learning
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Ie, animals using stable landmarks to find nests
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Associative Learning
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Associating one feature of the environment with another. Pavlov; Offer meat, dog salivates, ring bell. Arbitrary stimulus assc. with reward/punishment.
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Classical conditioning
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ring bell, dog salivates. (part of assc. learning)
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Operant Conditioning
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(part of assc. learning) animals learn to assc. one if its behaviors with a reward or punishment, then tends to repeat or avoid that behavior. Trial and error learning.
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Signal
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Behavior that causes a change in another animal. These combine to form a communication system. Evolution of signal type related to lifestyle and environment (chemical visual auditory tactile electrical)
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Acoustic Communication
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Some signals (calls) partially learned, others under genetic control.
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Animal Cognition
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Ability of an animal to perceive, store, process, and use information. Tools to solve problems- watching others,
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Sexual selection
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Mate choice and mating behavior.1) seeking/attracting mates 2)competing for mates 3)choosing among potential mates
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Intrasexual Selection
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Ie, between two of the same gender. Weapons competition, competitive behavior
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Intersexual selection
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F choosing males for elaborate color, ornaments, behavior.
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Promiscuous Mating System
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Exactly what it sounds like. Example: ASU.
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Altricial vs. precocial babies
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Altricial- males needed to help rear young
Precocial-One sex can care and feed young, males better off finding new mate |
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Certainty of paternity
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Prompts male behavior that increases certainty; to guard females, sperm competition. More paternal certainty=more paternal care, and vice versa.
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Inclusive fitness
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Fitness of self + Fitness of kin who share percentage of the same alleles.
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Hamilton's Rule
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Coefficient of relatedness, or r, times benefit of the altruistic act to the organism (or person) benefitting=B, must be greater than the cost of the action, or c, for an organism to give up its life to help another.
So rB>c |
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Population
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Group of organisms that interbreed and live together in the same place at the same time.
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Important Characteristics of Populations
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Population Size- Total n of indl's in pop
Population Density- total n of indl's in pop per area/volume Population Dispersion-patterns of spacing among indl's Sex Ratio-ratio of m to f Age structure- how many indl's in each age class Schedules of survival and reporduction-how often do they have babies, how many?, how long do they live |
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Measuing Pop
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1) through census (directly)
2) density x area/vol occupied (indirectly) 3) estimate through mark/capture analysis (ecobeaker) |
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Clumped distribution
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Pop. in clumps/patches
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Uniform distribution
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spacing is roughly constant, reflects territoriality
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Random distribution
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Random, duh. reflects homogenity of resources and weak interactions.
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Heterogeneous Populations
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can include genetic variations, two sexes (usually), diff. life stages and sizes
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Age structure pyramids
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Broad based-rapid growth, many kids
Flat sided- slow growth Pinched botton- slow decreasing from low birth rate |
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Mortality Rate
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Probability of dying/unit of time
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Survival Rate
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Probability of surviving/unit of time
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Types of survivorship curves
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I) mortality rate increases later in life, eg large mammals
II) mortality rate constant over life, eg birds/reptiles III) mortality rate highest in young eg marine organisms |
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Iteroparity vs Semelparity
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Iteroparity- Repeated reproduction
Semelparity-breed once or briefly and then die, "big bang breeding" |
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Reproduction Schedules
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Include age of first breeding, breeding frequency, litter size,
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Population Growth
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Dependent on birth rate and mortality. Growth rate= diff. between the two.
Delta n (change in pop size)/delta t(change in time)=b (births)-d(deaths) |
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Birth rate (b)
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Number of births per individual per time
(B=abs. number of births) (N=# of indl's at beginning of period) b=B/N |
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Death Rate (d)
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Death rate (d) is the number of deaths per individual per time
(D=abs. number of deaths) (N=# of indl's at beginning of period) d=D/N |
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Community
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Assemblage of species that occur together in the same place
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Clement's discrete unit
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Community is superorganisms, various species work like part of a body. Species coevolve to enhance interdependent functioning. communities=discrete entities w/recognizable boundaries.
An INDIVIDUALISTIC view. |
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Gleason's Loose assemblage of species
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community=fortuitous association of species whose adaptations/requirements allow them to live together under particular conditions of a place. Component species= occur together by coincidence
No boundary where one community meets another.A HOLISTIC view. |
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Species Richness
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Measure captures difference in tropical, boreal, and temperate regions
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Autotrophs
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Photosynthesizers/primary producers
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Heterotrophs
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directly/indirectly consume energy rich molecules made by the primary producers
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Consumer levels
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herbivores- primary consumers
organisms that eat herbivores= secondary consumers organisms that eat secondary consumers=tertiary consumers |
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Dentritivores
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Eat dead things/waste
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Ecosystem services
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provisioning, regulating, cultural, supporting (ie Millenium Ecosystem Assessment). Assess ecosystems, services, importance to humans (dur).
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Barriers to sustainable management
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Education
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Conservation Biology
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Evolution is the process that unites all biology, the ecological world is dynamic, humans are part of ecosystems
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Restoration Ecology
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Degraded ecosystems and disturbance patterns can be resotred
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Invasive Species
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Controlled spread of these important (conservation bio)
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Reconciliation Ecology
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Sustainable practices in agriculture, industry, business
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CITES
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Uses the market to influence exploitation (Strategies for Conservation Biologists)
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Protected areas
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Protected areas to preserve habitat and prevent overexploitation
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Summary of Conservation Bio
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The key to human survival: development of sustainable interactions within biosphere.
Local Threats: overexploit. resources, intro exotic species Global Threats: global warming Solutions: new attitudes toward sustainability and self restraint |
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Measure growth rate
Rmax * N((K-N)/K) |
rate times number of individuals times times carrying capacity minus number divided by carrying capacity
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Exponential Growth Rate (Intrinsic Population)
b-d*n |
births minus death times number of individuals
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