Biology Exam 3

interdependent groups of biological entities forming a unified whole that functions in an ecological context.

Allowing us to manage very complex systems

Example: Watershed

1. Temperature

2. Water

3. Sunlight

4. Soil

5. Phenotypic Plasticity: Changes that are not due to differences in genetic material.

6. Physiological Changes at high elevation: Increased breathing, Raising the amount of hemoglobin in the blood, and increasing the rate at which oxygen is unloaded in body tissues

Remember the word “balance”

Examples: Sweating, body temperature control, shivering

An organism’s lifetime pattern of growth, development, and reproduction

The number of lifetime breeding events

The number of offspring

Fast (r-selected) “Live Fast, Die Young”

• Short lives

• Many offspring with no parental care

• Early age of sexual maturity

• Unstable Conditions

Example: Bull Frog

Slow (k-selected)

• Long lives

• Few offspring with lots of parental care

• Delayed age of sexual maturity

• Stable Conditions

Example: Humans, Elephants

multiple reproductive episodes

Breed a single time during their entire life

Evolve when:

• Preparation for reproduction is costly

• A lot of variation in the playoff from reproduction

• An anti-predator mechanism (Cicadas)

The area throughout which a population occurs.

The movement of individuals from one area to another

1. Random spacing (Live Fast, Die Young)

   • Not dependent on any particular resources

2. Uniform Spacing

   • Compete heavily over resources

3. Clumped Spacing

   • Strong Social Interactions

A population of populations

Sources

• Found in high-quality habitat patches

• High reproductive success

Sinks

• Low quality habitat patches

• Low reproductive success

Type 1:

• Examples: Humans, Barnacles

• k-selected species

• produce small amounts of offspring

• quality over quantity approach

Type 2:

• Linear relationship

• mortality rate and survivorship rate are consistent across time

• Example: Squirrels

• Likely to die in year 8

Type 3:

Examples: Green tree frogs

• Do not survive well early on in life

• r-selected lifestyle

Influence population size without having anything to do with initial population size

• Fires

• Floods

• Hurricanes

a winning species can only colonize after a losing species has already arrived

one species prevents the other from colonizing

How communities change over time

referred to the establishment and development of communities in a newly formed habitat that has no life at all

The regeneration of a community following disturbance

when two or more species reciprocally affect each other's evolution through natural selection

one species benefits from the close, prolonged interaction, while the other neither benefits nor is harmed

specialized to obtain energy and nutrients

One species defends the other in return for food or shelter

Involves the transport of seed and pollen

Two species that are so closely associated have co-evolved together to such an extent that at least one of the members is completely dependent on the other and cannot survive without the other

Two organisms do interact with one another but they are not completely dependent

One type of these relationships is where both species involved benefit to some extent, with neither species being harmed