Chapter 5: Recap (11)

Question 1

Competition

Answer 1

Members of one or more species interact to use the same limited resources such as food, water, light, and space

Question 2

Interspecific Competition

Answer 2

Competition between different species

Question 3

Intraspecific Competition

Answer 3

Competition within the same species

Populations can develop adaptations that enable them to reduce or avoid competition with other species

Question 4

Resource Partitioning

Answer 4

Reduce competition by feeding in different portions of certain spruce trees and by feeding on different insect species

Evolution of specialized feeding niches

Question 5

Predation

Answer 5

Strong effect on population sizes and other factors in many ecosystems

Predators and prey have evolved many skills/adaptations: walking, flying, etc.

Question 6

Coevolution

Answer 6

Gene pool of one species leads to changes in the gene pool of another species, back-and-forth adaptation

Changes occur in both species that help them to become more competitive or to avoid or reduce competition

Question 7

Parasitism

Answer 7

When one species (the parasite) lives in or on another organism (the host)

Question 8

Mutualism

Answer 8

Two species interact in ways that benefit both by providing each with food, shelter, or some other resource

Question 9

Commensalism

Answer 9

Interaction that benefits one species
but has little, if any, beneficial or harmful effect on the other

Question 10

Population Control

Answer 10

Population: group of interbreeding individuals of the same species

Population Size: number of individual organisms in a population at a given time

Increase in population
- Births
- Immigration

Decrease in population
- Deaths
- Emigration

Question 11

Limiting Populations

Answer 11

• Range of Tolerance
• Limiting Factors

Population Growth:
J Curve:
- exponential growth
- resources plentiful
- reproduce at an early age
- have many offspring each time
- short intervals between generations
S Curve:
- sunlight, water, temperature, space, or nutrients, or exposure to predators or infectious diseases → Carrying capacity
- J curve converts to S when carrying capacity is met

Question 12

Reproductive Patterns: r-selected species

Answer 12

r-selected:
- Energy into reproduction not survival
- Poor competitors
- Opportunists–take advantage of favorable conditions, changes in environment
- When favorable conditions are gone, population may crash
- Populations go through irregular or unstable cycles

Question 13

Reproductive Patterns: r-selected species (General Characteristics)

Answer 13

• Small-bodied
• reproduce when young. many offspring, low survival
• Little to no parental care
• Exponential growth
  exhibit type III survivorship curve
• Examples: bacteria, algae, most annual plants, dandelions, most insects, cockroaches, rodents, oysters

Question 14

Reproductive Patterns: K-selected species

Answer 14

• Energy into long term survival
• High parental care
• Good competitors
• Thrive best in ecosystems with fairly constant environmental conditions
• Populations remain close to carrying capacity (K) over long periods of time

Question 15

Reproductive Patterns: K-selected species

Answer 15

• Larger-bodied
• Late reproduction→fewer offspring→most survive
• High parental care
• Live in predictable environments
• Controlled by density-dependent factors
• Exhibit type I survivorship curve
• Examples: Humans, large trees, polar bears, Elephants, Most mammals/birds

Question 16

Survivorship Curves

Answer 16

The percentages of the members of a population surviving at different ages
- Type I / Late loss: high survivorship to a certain age, and then high mortality (K-selected species)
- Type II / Constant loss: constant death rate at all ages
- Type III / Early loss: survivorship is low early in life (r-selected)

Question 17

Surtsey: Primary Succession Example

Answer 17

Surtsey: A natural laboratory for the study of primary succession.
Island created in November 1963

Question 18

Early Succession

Answer 18

Facilitation

Early loss species common

Annual weeds

Species with broad niches

Generalist species

Organisms are small

Many sun-loving producers

Pioneer Community

Harsh environment

Biomass increasing

Energy consumption inefficient

Some nutrient loss

Low species richness

Fluctuations common

r – selected species

Question 19

Late Succession

Answer 19

Late loss species more common

Perennial Plants

Species with narrow niches

Specialists are common

Organisms are large

Many shade-loving organisms

Climax Community

Favorable environment

Biomass stable

Energy consumption efficient

Efficient nutrient cycling

High species richness

Fluctuations less common

K – selected species