of temperature or water scarcity and the adaptations of animals.
Temperature is the most important ecological factor. Average temperature on the
Earth varies from one place to another. These variations in temperature affect
the distribution of animals on the Earth. Animals that can tolerate a wide range
of temperature are called eurythermals. Those which can tolerate a narrow range
of temperature are called stenothermal animals. Animals also undergo adaptations
to suit their natural habitats. For example, animals found in colder areas have
shorter ears and limbs that prevent the loss of heat from their body. Also,
animals found in Polar regions have thick layers of fat below their skin and
thick coats of fur to prevent the loss of heat.
Some organisms exhibit various behavioural changes to suit their natural
habitat. These adaptations present in the behaviour of an organism to escape
environmental stresses are called behavioural adaptations. For example, desert
lizards are ectotherms. This means that they do not have a temperature
regulatory mechanism to escape temperature variations. These lizards bask in the
sun during early hours when the temperature