Lecture One - Ecology I

Question 1

Define organismal ecology.

Answer 1

The branch of ecology concerned with the morphological, physiological and behavioural ways in which an individual organism meets the challenges posed by their biotic and abiotic environments.

Question 2

Define population ecology.

Answer 2

Deals with the dynamics of species populations and how these population interact with the environment.

Question 3

Define community ecology.

Answer 3

The study of the interaction between the species within a community.

Question 4

Define ecosystem ecology.

Answer 4

Study of the interaction between biotic and abiotic components of ecosystems.
Note: Ecosystem - a biological community of interacting organisms and their environment.

Question 5

Define landscape ecology.

Answer 5

Landscape ecology is the study of the pattern and interaction between ecosystems within a region of interest, and the way the interactions affect ecological processes.

Question 6

Define global ecology.

Answer 6

Relationships of organisms with one another and their environments on a global scale.

Question 7

List factors limiting distribution.

Answer 7

• Dispersal
• Species transplants
• Behavioural and habitat selection
• Biotic and abiotic factors
• Fire
• Water
• Salinity
• Sunlight
• Rocks and soil
• Climate including:
• Glbal climate patters
• Seasonal pattens
• Global circulation
• Wind patterns
• Proximity to bodies of water
• Mountains
• Seasonality

Question 8

Define dispersal.

Answer 8

Movement of individuals away from centres of high population density or from their area of origin.

Question 9

How do species transplants affect distribution?

Answer 9

• Species transplants occur when organisms are accidentally or intentionally relocated from their original distribution.
• Transplants often disrupt the communities or ecosystems to which they are introduced.
• E.g. The introduction of the Cane Toad into Australia.

Question 10

How does behaviour and habitat selection affect distribution?

Answer 10

• Some organisms do not occupy all of their potential range.
• Species distribution may be limited by habitat selection behaviour.

Question 11

Name biotic factors that can affect distribution.

Answer 11

• Interactions with other species
• Predation
• Competition

Question 12

Name abiotic factors that can affect distribution.

Answer 12

• Temperature
• Water
• Sunlight
• Wind

Question 13

How does fire affect distribution?

Answer 13

Plants have evolved to:
- Reseed: Self-sown seeds.
- Resprout: Some plant species are able to survive fire by the activation of dormant vegetative buds to produce regrowth.
Plants may resprout by means of lignotubers at the base of epicormic buds on the trunk or major branches.

The frequency and intensity of fires influences species composition and vegetation.

Question 14

How does water affect distribution?

Answer 14

Availability of water affects species distribution.

Question 15

How does salinity affect distribution?

Answer 15

Affects water balance of organisms through osmosis.

Question 16

How does sunlight affect distribution?

Answer 16

• Intensity and quality affect photosynthesis.

- Water absorbs light, therefore in aquatic environments most photosynthesis occurs near the surface.

Question 17

How do rocks and soil affect distribution?

Answer 17

• The physical structure of the rocks and soil affect what can live in that environment.
• The pH of the soil
• The mineral composition of the rocks and soil.

Question 18

Define a macro climate.

Answer 18

Consists of patterns on the global, regional and local level.

Question 19

Define micro climate.

Answer 19

Consists of very fine patterns, such as those encountered by the community e.g. under a called log.
A local atmospheric zone where the climate differs from the surrounding area.

Question 20

How are global climate patters determined?

Answer 20

Largely by the solar energy and the planets movements in space.

Question 21

How can seasonal patters affect distribution?

Answer 21

The varying light levels and temperatures can have an effect on distribution patterns.

Question 22

How can global circulations affect distribution?

Answer 22

Air circulation and precipitation patterns help determine climate patters, which in turn, help determine where organisms can survive and live.

Question 23

How can wind patterns affect distribution?

Answer 23

Air flowing close to the Earths surface creates predictable global wind patters. These wind patterns help to determined where organisms can survive and live.

Question 24

How can the proximity to bodies of water affect distribution?

Answer 24

oceans and large lakes moderate the climate of near by terrestrial environments, making these environments suitable for particular organisms to exist.

Question 25

How can mountains affect distribution?

Answer 25

They can affect the amount of light reaching an area, the temperature of an environment and its rainfall.

Question 26

How can seasonality affect distribution?

Answer 26

The angle of the sun leads to seasonal changes in local environments. This can affect the distribution of organisms in the effected area.

Question 27

How will long term climate change affect distribution?

Answer 27

• It will probable affect the biosphere.
• As the climate changes, species that have difficulty dispersing may have smaller ranges of could become extinct all together.

Question 28

Define Ecology.

Answer 28

The study of the interactions of organisms with their environment.

Question 29

Define biodiversity.

Answer 29

The relative abundance of organisms within a community or area.

Question 30

How can biodiversity be measured?

Answer 30

Species richness - The number of different species are in a community or area.
Species evenness - How well each species is represented.

Question 31

Define adaptive radiation.

Answer 31

The diversification of a single lineage in to multiple species that exploit a variety of different resource types and that differ in the morphological or physiological trait that are used to exploit these resources.
Adaptive radiation is a process in which one species gives rise to multiple species that exploit different niches in the environment.

Question 32

Explain the individualistic hypothesis.

Answer 32

Suggests that organisms are found in a particular environment because they share the same/similar abiotic requirements as another species.

Question 33

Explain the interactive hypothesis.

Answer 33

Suggests that organisms are grouped together because they interact and are involved with one another.

Question 34

Define climate.

Answer 34

The average atmospheric conditions (temperature, precipitation, humidity) prevailing in an area over many years.

Question 35

Define the word biome.

Answer 35

Ecosystems that share major similarities (similar biotic and abiotic factors) are called biomes.
E.g. Deserts and tropical forests are biomes.

Question 36

Define biosphere.

Answer 36

All the ecosystems on the earth grouped together make up the biosphere - the global ecosystem.

Question 37

Define and differentiate between endangered and threatened species.

Answer 37

Endangered species are species that are at risk of becoming extinct.
Threatened species are species that are a risk of becoming endangered in the near future.

Question 38

Define an invasive species.

Answer 38

A species not naturally found in an ecosystem and who’s introduction into that ecosystem may cause economic or environmental harm.

Question 39

Define species diversity.

Answer 39

measurement of community diversity that incorporates both species evenness and species richness.