Ecology and Evolution

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Ecology and Evolution

• Introduction (cont.)

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• Ecological Revolution

N
i.r.
time
Haeckel 1870s Broadens Ecology
?Need for understanding human impact on
planet including studying organisms and their
surroundings
Human Population Explosion ?Materialism
?Resource exploitation ?Habitat (Environmental)
Quality
Darwin 1859 Origin of Species
Industrial Revolution
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Biological Hierarchies
Habitat place or physical setting in which and
organism lives
Ecological Revolution at all scales of
ecological hierarchy.
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and at all levels of species diversity
when ecologists take into account the
evolutionary relationships among organisms.
Evolutionary hierarchy
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How does the physical (abiotic) environment
affect life on earth?

• Concept behind the idea of the habitat
• The abiotic environment tends to place
  constraints on life.
• example
• blood and tissues of vertebrates tend to freeze
  above temperatures found in antarctic waters.

Notothenoid fish -1.9 C glycopeptide and peptide
antifreeze compounds Outer-tissues have ice on
them and the spleen
Biology solutions
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Other constraints

• Gravity
• solutions
• Flight wings, metabolic level
• Gliding mammals, frogs, snakes
• Bones
• Arid Environments
• (no water for photosynthesis)
• solutions
• Cactus waxy outer covering,
• stomata, ?storage capacity,
• suberized roots etc.

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Main points

• Live exists in constant tension with its abiotic,
  physical surroundings (habitat)
• Tolerance for extremes for chance to reproduce.
• Reproduction
• Growth and repair
• Survive and maintain

Energy available
Life and Ecosystems are in a state of
non-equilibrium
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Consideration of some abiotic elements important
for life

• Water
• Abundant on Earth
• Excellent solvent
• Facilitates the movement of many organisms
• Main ingredient in photosynthesis
• Remains in liquid state over a large range of
  temperatures
• Resists change in state
• to freeze remove 80cal/g
• to evaporate add 500cal/g
• Thermal inertia
• Density and Temperature

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Density and temperature of water

• Substance X
• cools becomes more dense

• Water
• cools becomes more dense to about 4
• then expands! (ice floats)

Why important? Bottoms of bodies of water do not
freeze floating layer of ice layer of snow
insulation
dormant plants and reproductive bodies
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Excellent solvent

• Natural waters contain dissolved substances that
  are building blocks of life

B. Solutes Na, Cl, Mg, SO4 N nucleic acids,
protein P na, phospholipids, bone S
proteins K solute in animal cells Ca bone,
plant structures Fe Proteins (hemeglobin)
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C. Carbon and Oxygen

• solutes that receive special mention
• Immediately tied to life via
• acidity
• respiration and photosynthetic reactions

D. Light and Heat

• Sources of heat
• Sun
• Geothermal
• Metabolic