Transcript video slide - dannenbergapbiology

Organisms and the Environment
• The environment of any organism includes
– Abiotic, or nonliving components
– Biotic, or living components
– All the organisms living in the environment, the
biota
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• Environmental components
– Affect the distribution and abundance of
organisms
Kangaroos/km2
> 20
10–20
5–10
1–5
0.1–1
< 0.1
Limits of
distribution
Figure 50.2
Climate in northern Australia
is hot and wet, with seasonal
drought.
Southern Australia has
cool, moist winters and
warm, dry summers.
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Red kangaroos
occur in most
semiarid and arid
regions of the
interior, where
precipitation is
relatively low and
variable from
year to year.
Southeastern Australia
has a wet, cool climate.
Tasmania
Subfields of Ecology
• Organismal ecology: Adaptations
– Studies how an organism’s structure,
physiology, and (for animals) behavior meet
the challenges posed by the environment
Figure 50.3a
(a) Organismal ecology. How do humpback whales
select their calving areas?
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• Population ecology: Why we sample
– Concentrates mainly on factors that affect how
many individuals of a particular species live in
an area
(b) Population ecology.
What environmental
factors affect the
reproductive rate of
deer mice?
Figure 50.3b
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• Community ecology
– Deals with the whole array of interacting
species in a community
(c) Community ecology.
What factors influence
the diversity of species
that make up a
particular forest?
Figure 50.3c
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• Ecosystem ecology: Where do you get your
energy?
– Emphasizes energy flow and chemical cycling
among the various biotic and abiotic
components
(d) Ecosystem ecology. What
factors control photosynthetic
productivity in a temperate
grassland ecosystem?
Figure 50.3d
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• Landscape ecology: Biome Business
– Deals with arrays of ecosystems and how they
are arranged in a geographic region
Figure 50.3e
(e) Landscape ecology. To what extent do the trees lining the
drainage channels in this landscape serve as corridors of
dispersal for forest animals?
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• Many naturalists
– Began to identify broad patterns of distribution by
naming biogeographic realms: Interactions between
organisms and the environment limit the distribution of
species
Palearctic
Nearctic
Tropic
of Cancer
(23.5N)
Oriental
Ethiopian
Equator
Neotropical
Figure 50.5
(23.5S)
Tropic of
Capricorn
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Australian
Biotic Factors
• Biotic factors that affect the distribution of
organisms may include
– Interactions with other species
– Predation
– Competition
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• Interspecific interactions
– Can have differing effects on the populations
involved
Table 53.1
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Trophic Structure: a key factor in community dynamics
• Food chains
– Link the trophic
levels from
producers to top
carnivores
Quaternary
consumers
Carnivore
Carnivore
Tertiary
consumers
Carnivore
Carnivore
Secondary
consumers
Carnivore
Carnivore
Primary
consumers
Zooplankton
Herbivore
Primary
producers
Plant
Figure 53.12
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A terrestrial food chain
Phytoplankton
A marine food chain
Abiotic Factors
• Abiotic factors that affect the distribution of
organisms may include
– Temperature
– Water
– Sunlight
– Wind
– Rocks and soil
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• Climates
– Are determined largely by the input of solar
energy and the planet’s movement in space
LALITUDINAL VARIATION IN SUNLIGHT INTENSITY
North Pole
60N
Low angle of incoming sunlight
30N
Tropic of
Cancer
Sunlight directly overhead
0 (equator)
Tropic of
Capricorn
30S
Low angle of incoming sunlight
60S
South pole
Figure 50.10
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Atmosphere
Climate and Terrestrial Biomes
• Climate has a great impact on the distribution
of organisms, as seen on a climograph
Temperate grassland
Desert
Tropical forest
Annual mean temperature (ºC)
30
Temperate
broadleaf
forest
15
Coniferous
forest
0
Arctic and
alpine
tundra
15
100
Figure 50.18
200
300
Annual mean precipitation (cm)
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400
• Many aquatic biomes
– Are stratified into zones or layers defined by
light penetration, temperature, and depth
Intertidal zone
Neritic zone
Littoral
zone
Limnetic
zone
0
Oceanic zone
Photic zone
200 m
Continental
shelf
Pelagic
zone
Benthic
zone
Photic
zone
Aphotic
zone
Pelagic
zone
Benthic
zone
Aphotic
zone
2,500–6,000 m
Abyssal zone
(deepest regions of ocean floor)
(a) Zonation in a lake. The lake environment is generally classified on the basis
of three physical criteria: light penetration (photic and aphotic zones),
distance from shore and water depth (littoral and limnetic zones), and
whether it is open water (pelagic zone) or bottom (benthic zone).
Figure 50.16a, b
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(b) Marine zonation. Like lakes, the marine environment is generally
classified on the basis of light penetration (photic and aphotic zones),
distance from shore and water depth (intertidal, neritic, and oceanic
zones), and whether it is open water (pelagic zone) or bottom (benthic
and abyssal zones).