Biogeography 1301

Ecology
scientific study of the
relationships between organisms and their
environment(s)
Biogeography
scientific study of the
relationships between organisms and their
environment(s), with an emphasis on changes in space (Spatial Ecology)
Physical/chemical influences on organism’s physiology
Temperature, Light, Oxygen, Carbon dioxide
Ecosystem
Biotic and abiotic interactions
Study: flow of energy through ecosystems
Organism interaction Hierachy
Individual, Population, Community, Ecosystem, Landscape, Biome, Biosphere
I Personally Cannot Empathize with Lying Bumble Bees
Populations
groups of same species in 1 area
Compete for resources, predator-prey, or mutually beneficial
Study: Birth/death rates, ditribution
Community
All populations in an ecosystem
Study: factors influencing relative abundance
Landscape
the area of land (or water)
that is composed of different communities
and ecosystems
– At this level, communities and ecosystems are
linked by the dispersal of organisms and the
exchange of materials
Biomes
geographic regions with similar
geological and climatic conditions
Study: patterns of diversity
Field Study
examines natural patterns across the landscape
– The relationship between two or more variables is
studied
– The results suggest a relationship but do not prove
cause and effect
Experiment
test under controlled conditions and controls the
independent variable in a predetermined way
(In a lab, is very controlled, can’t be directly applied)
Field Experiment
Test applied to natural setting
(difficult to control other influencing factors, but results are realistic)
Categorical Data
observations fall into categories, qulaitative, nominal (unorded) + ordinal = binary
Numerical Data
quantitative, discrete (only certain numbers) or continuous (any value)
Frequency distribution
frequency of a given value (bar graph/histogram) , used with continuous data
Habitability
ability of the physical
environment to support life
solar radiation
electromagnetic energy or stream of photons produced by the sun. Measured in wavelength and frequency. Hotter = shorter wave. Only 51% reaches Earth’s surface
visible light
electromagnetic radiation from 400-700 nanometers wavelength. aka Photosynthetically Active Radiation
Earth’s tilt
23.5 degrees
Equinox
Spring and autumn, sun directly at equator
Sostice
Winter and Summer, sun directly at Tropic of Cancer or Capricorn
Environmental Lapse Rate
the rate at which temperature decreases with altitude, Altitude up, temp down
Atmospheric Regions
Troposphere-Stratosphere-Mesosphere-Thermosphere
separated by pauses
Adiabatic Cooling
decrease in air temperature through expansion rather than
through heat loss. Depends on moisture in air. Causes mountain shadow effect
Coriolis Effect
the deflection in the pattern of air flow due to differences in rotation speed (Santa example) Creates air cells and belts
Westerlies
the currents that move toward the poles (away from the Hadley cells) and are diverted to the right by the Coriolis effect
trade winds
the currents that move toward the equator (away from the Hadley cells) and are deflected to the right by the Coriolis
effect
Ferrel Cells
air loops where westerlies and polar airs mix
gyres
circular water currents (2 in each ocean)
Intertropical Convergence Zone (ITCZ)
the region that forms where the trade winds meet and is characterized by high amounts of precipitation. migrates to area with warmest surface temp
alleles
different forms of genes (dominant, recessive, codominant)
genome
all DNA in a cell
genotype
The particular combination of alleles present at a
locus
phenotype
physical expression of genotype
genetic drift
the change in allele frequency due to random chance associated with sexual reproduction
cline
a measurable, gradual change over a
geographic region in the average of a phenotypic
trait
ecotype
a population adapted to its unique
(often abrupt) local environmental conditions
Adaptive Radiation
the process in which one
species gives rise to multiple species that exploit
different features of an environment (food,
habitat)
Phenotypic plasticity
the ability of the genotype to give rise to different phenotypes under different environmental conditions.
2 types: developmental (irreversible, reallocation of biomass during growth) and Acclimation (reversible, individual’s response to change)
norm of reaction
the set of phenotypes expressed by a single genotype across a range of environmental conditions
Unitary vs Modular
Unitary -individual is unique genetically (genet)
Modular – produces similar modules (common in plants)