Distribution of Organisms: Introduction
1. Why are organisms of a particular species present in some places and absent from others??
2. Salmon species # different in Pacific vs Atlantic - Applied aspects of distribution.
3. Distributions over time (African honeybee) - Applied aspects of distribution.
4. Experimental Tool: 1. Transplant experiments
Outcome of transplant experiments
Successful
Unsuccessful
5. Liebig's law of minimum
�Justus Liebig (1803-1873) German chemist
�Biochemistry: Q: How plants transform inorganic nutrient to organic matter?
�Postulated 1840 rate of any biological process limited by factor in least amount
�Add the limiting nutrient increase crop production.
�In nature usually not limited by one factor
�Interacting factors may be important � ex. temperature & moisture
�Experimentally important to add complexity in ecophysiological experiments
Experimental Tool: 2. Physiological ecology - Shelford's work
�Animal ecologist
�Organism must be able survive, grow, reproduce in particular environment
�Distribution species in communities function of physiological tolerance
�Short-term physiological adaptation: osmotic adjustment
�Behavioral modifications (hibernation)
�Evolutionary adaptations genotypic variability Natural selection
Factors controlling species distributions � A stepwise analysis
Alternative factors limit distributions: Biotic vs Abiotic
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