What is ecology? - Wikispaces-+10.25.10... · Habitat & Niche • Habitat is the ... – Habitat...
Transcript of What is ecology? - Wikispaces-+10.25.10... · Habitat & Niche • Habitat is the ... – Habitat...
4
What is Ecology??
• The study of interactions that take place between organisms and their environment.
• It explains how living organisms affect each other and the world they live in.
copyright cmassengale
• Biosphere
• Ecosystems
• Community
• Population
ECOSYSTEM LEVELEucalyptus forest
COMMUNITY LEVELAll organisms ineucalyptus forestPOPULATION LEVEL
Group of flying foxes
ORGANISM LEVELFlying fox
ORGAN SYSTEM LEVELNervous system
ORGAN LEVELBrain
Brain Spinal cord
Nerve
TISSUE LEVELNervous tissue
CELLULAR LEVELNerve cell
MOLECULAR LEVELMolecule of DNA
Figure 1.1
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
• A Hierarchy of Interactions
SUMMARY OF KEY CONCEPTS
Visual Summary 18.1
Organism ecology
(individual)
Population ecology
(group of individuals)
Community ecology
(all organisms in a particular area)
Ecosystem ecology (all organisms and
abiotic factors)
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
• A community
KEY PROPERTIES OF COMMUNITIES
– Is an assemblage of species living close enough together for potential interaction
Figure 19.2
8
Habitat & Niche• Habitat is the place
a plant or animal lives
• Niche is an organism’s total way of life
copyright cmassengale
9
The Nonliving Environment
• Abiotic factors- the nonliving parts of an organism’s environment.
• Examples include air currents, temperature, moisture, light, and soil.
• Abiotic factors affect an organism’s life.
copyright cmassengale
10
The Living Environment
• Biotic factors- all the living organisms that inhabit an environment.
• All organisms depend on others directly or indirectlyfor food, shelter, reproduction, or protection.
copyright cmassengale
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
• Inter-specific interactions are interactions between different species.
INTER-SPECIFIC INTERACTIONS IN COMMUNITIES
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
• Behavioral defenses:
– Alarm calls
– Mobbing
Figure 19.8
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
• Distraction displays:
– Direct the attention of the predator away from a vulnerable prey to another prey that is more likely to escape
Figure 19.9
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
• Camouflage, or cryptic coloration:
– Is a passive defense that makes a potential prey difficult to spot against its background
Figure 19.10
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
• In Batesian mimicry:
– A palatable or harmless species mimics an unpalatable or harmful model
Figure 19.12
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
• In Müllerian mimicry:
– Two or more unpalatable species resemble each other
Figure 19.13
Biotic factors• interactions with other organisms– Negative:
predation or competition
– Positive: facilitation (e.g., pollinators
urchin barrens
Fig. 50.9
Biotic and abiotic factors: adaptations
Predation - Aposematic coloration
Dry conditions - cacti
Predation – Cryptic coloration
Dry conditions – spring annuals
Abiotic factors• water availability
- too little water (desiccation)- Deserts, saltwater
- too much water (anaerobic)
Organ pipe cacti, desert shrubs
Mangroves
Abiotic factors• temperature
– high temperature cause cell membranes to leak and enzymes to stop working
– low temperature causes freezing
- some animals have antifreezes that allow them to survive below freezing temperatures.
Cool arctic fish (spp.?)
Thermophilic bacteria, Nevada
Abiotic factors• Sunlight
- Competition, shade tolerance for plants
- Photic zone, different wavelengths for aquatic organisms
Abiotic factors
• Wind– exacerbates the effects
of temperature and water loss
– also exerts forces on organisms (waves act in the same manner)
• The trophic structure of a community concerns the feeding relationships among the various species making up the community
Trophic Structure
Quaternary,
tertiary,and secondary consumers
Tertiary and
secondary consumers
Secondary andprimary consumers
Primary consumers
Producers (plants)
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
• Biomes:
– Are named for major physical or climatic features and for their predominant vegetation
Figure 19.33
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Figure 19.34a
• Tropical forest
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Figure 19.34e
• Temperate grassland
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Figure 19.31f
• Temperate deciduous forest
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Figure 19.34g
• Coniferous forest
Biodiversity
16 June 2010 45
• Variety of living things, number of kinds
• Ecological diversity– different habitats, niches,
species interactions• Species diversity
– different kinds of organisms, relationships among species
• Genetic diversity– different genes &
combinations of genes within populations
Benefits of Biodiversity
• Ecosystem functions• Ecosystem services
• Cleaning water,• Cleaning air,• Habitat & breeding
areas for wildlife, …• Aesthetic and
cultural benefits
16 June 2010 Biodiversity.ppt 46
Natural Resources• Vital economic natural resources
– Renewable• Forests (plants, wildlife) • Soils • Fresh water (lakes, rivers)• Wildlife and fisheries• Rangeland
– Nonrenewable• Minerals • Fossil Fuels
16 June 2010 Biodiversity.ppt 47
Threats to Biodiversity
• Extinction and population reductions– Hunting and overharvesting
• Tiger• Dodo• Whales• Sharks
– Habitat loss
16 June 2010 Biodiversity.ppt 48
Threats to Biodiversity
• Extinction and population reductions– Pollution– Climate change– Invasive species
16 June 2010 Biodiversity.ppt 49
Protecting Biodiversity
16 June 2010 Biodiversity.ppt 50
• How can we protect biodiversity– Stop overharvesting
• Sustainable yield• Hunting & fishing laws
(every state ?)– in developing nations ?
– Protect habitat • Refuges, parks, preserves
– Endangered Species Act
Protecting Biodiversity
16 June 2010 Biodiversity.ppt 51
• Biodiversity “hotspots”– Protection of habitat