Environmental Stress and Behavioural Adaptation

1. Front Matter

   Pages i-vi

   PDF

2. Introduction

   • John Davenport

   Pages 1-3

3. Temperature

   • John Davenport

   Pages 4-45

4. Salinity

   • John Davenport

   Pages 46-67

5. Oxygen Tension

   • John Davenport

   Pages 68-76

6. Desiccation

   • John Davenport

   Pages 77-86

7. Pollutants

   • John Davenport

   Pages 87-98

8. Conclusions

   • John Davenport

   Pages 99-105

9. Back Matter

   Pages 106-122

   PDF

It is generally agreed that animal life originated in the sea and that adaptive radiation subsequently led to the colonisaHon of other environments - shores and estuaries, streams and lakes, bog, mountain and desert. In their invasion of these habitats animals left the equable, relatively stabl.e surroundings of the open sea and subjected themselves to the rigours of temperature fluctuations and extremes, a variety of ionic backgrounds, areas of depleted oxygen or the possibility of aerial exposure and potential desiccation. The spur for this radiation presumably lay in the prize of access to unexploited habitats and sources of energy. The survival of these more adventurous species has depended upon them evolving mechanisms to protect the integrity of their cellular constituents. Protoplasm can only exist within physiochemical limits which are quite narrow for each species. Water activity, salt and gas concentrations and temperature all have to be appropriate for enzyme­ catalysed processes to function properly within cells. Except in the open sea, environmental conditions regularly vary outside these limits. To take a familiar example; humans can only remain conscious (and hence functional) if their core (Le. deep tissues - brain, heart, liver, etc.) body temperature is maintained between about 30 and 43°C.

• adaptation
• animals
• aquatic animals
• behavior
• desert
• energy
• environment
• environmental stress
• oxygen
• pollution
• receptor
• temperature
• thermoregulation
• tissue
• water

• Animal Biology Group, Marine Science Laboratories, Menai Bridge, UK

  John Davenport

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