Ch 40 – Animal Form & Function. Form & function. Evolution of Animal size & shape Constrained by physical forces Convergent evolution i.e. fusiform shape for aquatic animals. Seal. Penguin. Exchange with Environment. Mouth. Gastrovascular cavity.
Ch 40 – Animal Form & Function
(a) Single cell
(b) Two layers of cells
Advantages of a complex body:
Better able to deal with environmental changes
Countercurrent heat exchange – in many birds & mammals, also sharks, dolphins
Metabolic rate is the amount of energy an animal uses in a unit of time
How can metabolic rate be measured?
Influences on metabolic rate
Size – rate is proportional to body mass, smaller animals have higher metabolic rate per gram than larger animals
Reproduction – high energy cost
strategies: seasonal reproduction,
life history strategy – i.e. diapause (in insects)