3-Ecology

Question 1

WHAT IS ECOLOGY

Answer 1

scientific study of how organisms interact with each other and with their environment

Question 2

The two main goals of ecological research are to:

Answer 2

1. describe/quantify the patterns of distribution and abundance of organisms
2. Understand what factors can affect these patterns

Question 3

Distribution

Answer 3

where the organisms are

Question 4

Abundance

Answer 4

number of individuals or density of individuals

• varies with location and time
• Population size and/population density (number of individuals/unit area)
• population size/abundance can vary from location to location
• Varies with time

Question 5

AUTECOLOGY

Answer 5

• how do individuals interact with each other and the environment
  
  • What behaviour and/or physiological mechanisms do individuals use to meet ecological challenges

Question 6

Community ecologists

Answer 6

look at interactions between different species

Question 7

ECOSYSTEM ECOLOGY

Answer 7

How do energy and nutrients cycle through an ecosystem?

Question 8

Dispersal

Answer 8

• one-way movement of individual or gametes usually from a site where an individual is born to a new geographic area
  
  • Sometimes used interchangeable with migration

Question 9

examples of ABIOTIC factors that influence patterns of distribution and abundance

Answer 9

UV radiation
salinity, extreme pH levels
exposure to air, hypoxia/oxidative stress
extreme temperatures
currents, turbulence, and pressure
lack of sunlight

Question 10

examples of BIOTIC factors that influence patterns of distribution and abundance

Answer 10

parasitism
fouling
predation
competition for food
competition for space

Question 11

range of tolerance

Answer 11

organisms can survive in an area over the long term, only if abiotic conditions are within the organism’s range of tolerance

Question 12

a species distribution and abundance is determined largely by:

Answer 12

• Dispersal ability
  
  • Physical structures (oceans and mountains, etc) and climate can act as barriers to dispersal
• Abiotic factors (non-living)
  
  • Can organism survive the abiotic conditions (are conditions within the range of tolerance?)
    
    • optimal conditions — most abundant (all else being equal)
    • Stressful condition — less abundant
    • Beyond range of tolerance — not present except for very short time periods

Question 13

THE INTERTIDAL ZONE

Answer 13

The animals and algae that live in the intertidal zone Full time are marine organisms living at the edge of that ecosystem

thooooough being in the water is better for them

• hen tide is low, part/all of intertidal zone is exposed to terrestrial conditions
  
  • Conditions are suboptimal and potentially lethal
• When tide is high, most or all of the intertidal zone is exposed to marine conditions
  
  • Optimal conditions!!

Question 14

abiotic conditions and intertidal zone

Answer 14

abiotic conditions tend to determine the upper limit of distribution of an intertidal organism

• upper limit—how high they are found in the intertidal zone, how close are they found to the terrestrial environment
• Lower limit—how low down in the intertidal zone are they found—all the way down to the sub tidal zone or not?

Question 15

biotic conditions and the intertidal zone

Answer 15

in the intertidal zone — biotic conditions tend to limit lower limit of distribution

• predation intensity from marine predators is higher when intertidal organisms are submerged
• In general lower intertidal zone is favourable
• Competition for limited resources is more intense in locations where abiotic conditions are more optimal

Question 16

AUTECOLOGY

Answer 16

ECOLOGY OF THE INDIVIDUAL

how do individuals interact with each other and their physical environment?
- What morphological, physiological, and behavioural adaptations do individuals have allow them to meet the challenges posed by their environment?