Professor Richard Fortey joins Dr John Spicer on a night rock pooling expedition. They investigate the changing levels of dissolved oxygen in an intertidal environment at night and how the rock pool inhabitants' behaviour alters in response to this. At night the rock pool is an exciting and sometimes violent place as the high humidity allows normally submerged animals to venture out. Photosynthesis does not occur, therefore dissolved oxygen levels can decrease rapidly sometimes to zero. The glass shrimp has developed a behaviour pattern that allows them to survive the low oxygen levels. By becoming partially submerged in the water, they use a special “pump” in their body to keep oxygenated and this allows them to stay alive in a time of crisis.
Use this clip as an example of physiological and behavioural adaptations developed by animals to cope with common changes in their environment. Students can look for other examples of survival adaptations in the animal kingdom. They should relate their examples to optimum conditions for body systems to work efficiently. In the case of the glass shrimp, consider the energy costs of the behaviour they display as opposed to that of migrating with the tides.This and other examples of coping with extreme conditions could be considered in terms of changes to metabolism. Ask students what defences humans have against environmental changes, such as changes in temperature and to food and water supply. Investigate possible links between human cultural and behavioural practices and the climate they have developed in.