Keeping their cool

As the dog days of summer arrive and it’s hot and humid outside, we can usually escape to air conditioning or a shady area, wear light loose fitting clothing, and drink plenty of fluids to find some comfort from the oppressive conditions.  What do the wild animals do when it gets hot outside?  Animal adaptations to hot weather revolve around both behavioral and physiological adaptations.   

One very common behavioral adaptation involves modifying activity patterns to avoid the heat of the day by being most active in the early morning or evening hours.  Have you noticed how quiet it is during the heat of the day an comparison to the sounds of the early morning or nighttime hours? In the tropics and desert, a number of animals go into a summer hibernation called “aestivation” to lower their metabolic rate and conserve water. Some mammals and reptiles burrow deep into the ground to find cool resting places.  Birds can travel to milder areas or find cooler air currents on which to glide. Animals will use water to cool themselves either by splashing around in a water hole, covering themselves in mud, or urinating on their legs like vultures do.  Many animals cool themselves by panting or sweating.  Our family dogs dissipate heat from their mouths by panting or sweating from their paws.  Many birds fly with their mouths open in the summer months to cool themselves. Domestic and wild cats lick themselves to cool down. 

There are also a number of physiological adaptations animals have to help dissipate heat and conserve water.  A very common adaptation is changing a fur coat from thick and dark in the winter to a less dense and lighter color in the summer.  Many summer fur coats are thick on the top and very sparse on the underside which helps conserve water and increase airflow around the vital organs.  Elephants have the ability to tighten and loosen their blood vessels to force heat out of their body through their mouth; an elephant’s very large ears flap constantly to help dissipate water and cool themselves.  Reptiles have thick, scaly skin that prevents water loss.  Many desert animals have adaptations in their kidneys that allow them to conserve water so they do not have to drink very often. Last but not least, let’s not forget about the family pet that is pampered with air conditioning during hot days.

Article by Michael Kay, FCFCDB member

Nature Note for July 22, 2022