What is ecology?
- The study of interactions between organisms and their environment (or other organisms).
- Inlcudes biotic and abiotic factors
What are the scales used in ecology?
- Biosphere: the earth (all ecosystems)
- Ecosystem: all living/nonliving components (species, energy flow, nutrient cycling, etc)
- Community: all species/populations
- Population: one type of species
- Individual: single organism
- Temporal (time) scale is also involved
What are the steps in the scientific method?
- Analyze Data
- Publish data
What is life history?
- The major events of an organisms life that allows it to successfully reproduce
- How many seeds produced?
- Age of sexual maturity?
- Age of reproduction?
- How many offspring?
- What are the life stages?
What are the two types of reproductive selection?
- R selection: many offspring, not heavily invested, short lifespan
- K selection: Few offspring, heavily invested, longer lifespan
CASE STUDY: Robert MacArthur and 5 Warbler's occupying the same tree.
- Competitive exclusion: If there is a competition for identical resources the more fit species will drive the other to extinction
- Resource partitioning: Using identical resources differently (space, time, etc)
- Robert MacArthur noted that the Warbler's had becomes specialized to a specific areas of the trees rather than driving each other to extinction.
CASE STUDY: Dan Jansen and the decline of the Guanacaste tree
- Guanacaste tree is an angiosperm with very large fruits
- Determine that the population decline was tied to the seed dispersers going extinct 10,000 years ago
- Wrote a plan to use the exotic cattle and horses in the area as dispersers
What defines the terrestrial biomes?
Terrestrial biomes are distinguished by flora and climate.
What is the cause of the climactic variation on the earth? (re: heat)
- Uneven heating by the sun: seasonal change occurs because the earth's axis of rotation is tilted 23°
- Summer solstice: sun is directly overhead the tropic of Cancer
- Equinox: sun is directly over the equator
- The farther away from the equator causes a greater change in amount of sun received and thus, a greater seasonal change.
What is the cause of the climactic variation on the earth? (re: air)
- Sun heats the air at the equator causing it to expand/rise
- Warm/moist air cools as it rises, and forms clouds which produce heavy rainfall (tropics)
- This air spreads north and south, cools, and sinks back to the earth around 30°
- This air draws moisture from the lands over which it flows, creating deserts
- Air moves from 30° toward the equator (completing that air cycles)
- Warm air moves from 30° toward the poles rising and condensing to form clouds/precipitation, this air spreads northward and southward
Describe the Coriolis effect with directions.
- The wind actually moves east and west rather than directly north and south due to the rotation of the earth
- Polar north: east to west (down)
- 30°-60°N: west to east (up)
- E-30°N: east to west (down)
- 30°S-E: east to west (up)
- 60°S-30°S: west to east (down)
- Polar south: east to west (up)
Information about soil
- Defined by texture (particle size), horizons (layers), organic particles, and inorganic particles
- Creation: bedrock begins to disintegrate, organic materials facilitate disintegration (moss, lichen), horizons form, developed soil supports vegetation
- O horizon: organic layer
- A horizon: top layer, most fertile, most important for plants
- B horizon: less weathered, less organic material
- C horizon: parent materials (bedrock)
- Sand, silt, or clay