Unit 2.5 - Adverse conditions

• What prevents an organism expending excessive energy?

  Reduction in metabolic cost
• What is dormancy?

  Metabolic rate decreases to the minimum rate required to keep its cells alive. Energy is conserved ensuring they survive a period of adverse conditions. It can be predictive or consequential.
• What is predictive dormancy?

  Occurs before the arrival of the adverse condition and its usually genetically controlled
• What is consequential dormancy?

  When an organism becomes dormant after the arrival of adverse conditions. Common in regions of unpredictable climate. Advantageous as organism can exploit available resources for longer.
• What are examples of dormancy?

  Hibernation, aestivation and torpor.
• What is hibernation?

  Predictive dormancy that occurs in response to the threat of a metabolic crisis brought by low temperature and lack of food. Animals consume extra food to store as fat.
• What happens during hibernation?

  Metabolism decreases, body temperature decreases, heart rate slows, breathing rate slows, minimum energy expended.
• What is aestivation?

  Consequential dormancy that allows animals to survive periods of high temperatures and drought. Involves burying into the ground where the temperature is cool and reducing metabolic activity. Occurs in vertebrates and mammals.
• What is daily torpor?

  A period of reduced activity in organisms with high metabolic rates such as small birds and animals. Short-term hibernation.
• What happens during daily torpor?

  Decrease in heart rate, breathing rate and body temperature. Reduces energy required to maintain a high metabolic rate.
• What is the advantage of daily torpor?

  Reduces energy consumption by up to 90%.
• What is migration?

  Avoiding adverse conditions. It is the regular movement of members of a species from one place to another over a relatively long distance. Avoids metabolic adversity by expending energy to relocate to a more suitable environment. Can be innate or learned.
• What is innate migratory behavior?

  Inherited. Performed the same way by each member of the species. Occurs in response to an external stimulus.
• What is learned migratory behaviour?

  Experience. Result of trial and the transmission of knowledge and skills in a social group. Secondary role in migratory behaviour.
• What are examples of specialist techniques to study migration?

  Satellite tracking and leg rings.