Introduction to Ecology

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Chapter 50 Introduction to Ecology
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Ecology studies the interactions between
organisms and their environment. These
interactions determine
Distribution
Abundance
Where do they live?
How many are there?
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The distribution and abundance of organisms is
determined by the interactions between organisms
and their environment
Abiotic
(nonliving components)
(living components)
Biotic
Relative importance of each component
Distribution during Feb-Mar 2000-2001 from visual
surveys
0 m
Fin whale Balaenoptera physalus
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Balaenoptera physalus Gulf of California
population
BBCt
B. Tershy
Dainet
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Interactions between organisms and their
environment that occur over a long enough period
of time promote evolutionary change.
Hawaiian crickets, one of the highest rates of
speciation
Apparently, sexual selection
500 species of cichliids from Lake Malawi in the
last 1 million years
First, trophic morphology subsequently, sexual
selection
Nature 2005
T. D. Kocher
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Population ecology limiting factors
Organismal ecology coping
Community ecology interspecific interactions and
diversity
Ecosystem ecology energy flow and chemical cycling
Landscape ecology effects on interactions at
lower levels
Biosphere ecology global effects
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DISPERSAL Accidental or deliberate introduction
Fig. 50.8
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BEHAVIOR/HABITAT SELECTION
Avoidance of certain areas
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BIOTIC FACTORS
Predation, competition, parasitism, disease,
pollination
Fig. 50.9
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ABIOTIC FACTORS
TEMPERATURE, WATER, sunlight, wind
Climate
Effect on biological processes. Most organisms
unable to regulate body temperature.
Aquatic water balance. Terrestrial desiccation.
Provides energy to photosynthetic
organisms. Photoperiod cuing of daily and
seasonal cycles.
Increases heat and water loss. Affects plant
morphology.
Salinity, pH, rocks, soil, oxygen, density
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Solar radiation and latitude
Fig. 50.11
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Seasonal variations
Fig. 50.12
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Seasonal effects on climate in the ocean
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Upwelling index
Sea surface temperature
Monterey Bay
Productivity
Krill backscatter
Chlorophyll
Blue whale sightings
Data from D. Croll
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Local effects on climate
Fig. 50.14
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Largest component. Vertical stratification
light, temperature, salinity, density. Oceans (3
salt) rainfall, climate, wind. Give O2 and take
CO2. Freshwater (lt 1 salt) linked to soil and
biota of terrestrial biomes.
Aquatic Biomes
Fig. 50.17
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Ocean zonation
Fig. 50.22
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Terrestrial Biomes
Fig. 50.24