What’s your secret to with standing the sweltering summertime? To animals, including humans, heatstroke is the deadliest challenge in living through the scorching season. Therefore, we are all looking for ways to cool down and sustain body mechanics. Urban people may simply stay indoors for the air-con. What about animals in the wild? What tactics do they resort to?
Many species have developed thermoregulation, i.e. the ability to regulate body temperature, to adjust heat absorption and emission to adapt to the environmental temperature. Physiological and behavioural adjustments are the two major means of managing heat flow in the body. The former employs physical changes to take heat out of the body (e.g. through perspiration), while the latter reduce heat through behavioural adaptations. Below are the five ways of how wild animals keep their cool under the searing sun.
Adaptation No.1 - Colouring
As noted in physics, electromagnetic waves react differently to different colours. While black objects absorb light, converting it to heat energy, white objects reflect it. In other words, changing skin colour can help animals to moderate the absorption of environmental heat. Studies show that colour changing is an ability that lizards employ to maintain their body temperatures at a favourable level. The higher the temperature is, the paler a lizard's skin looks. In recent years, engineers developed colour-switching electrochromic glass, to regulate the temperature in buildings. This ground breaking design may have been inspired by the lizard’s lore.
Adaptation No.2 - Panting
Wondering why your beloved puppy pants more heavily in the dog days of summer? The fact is, quickly repeated inhalation and exhalation can carry heat out of the body more effectively. Similar behaviour can also be observed in birds. Resting in trees, the Cormorant (Phalacrocorax carbo) pants by vibrating its throat, while its beak is open - how cost-effective it is!
Adaptation No.3 - Escape
If you can’t beat the fierce sunlight, just shut it out! Human tends to keep below ceilings to block the sun during daytime. Likewise, animals in the wild may use the shade from leaves to guard against excessive sun exposure. In order to reduce the heated area, some dragonflies raise their rears up. Furthermore, instead of wasting energy to confront burning sunlight, pond loaches simply bury themselves in the soil and sleep through the sunny days.
Adaptation No.4 - Airflow
To diminish body heat, people in the Western Han dynasty created artificial airflows by waving handheld fans back-and-forth. Such intelligence is not exclusive to human beings. Born with a pair of handy “fans”, an elephant waves its big broad ears to dissipate the head’s heat. Living in a harsher habitat, African Elephants have even bigger ears to defeat the savanna heat.
Adaptation No. 5 - Soaking
On summer days, swimming pools are usually thronged with people seeking a thorough cool down. Ponds in nature are the best cooling spots for rhinoceros, buffalos and wild boars, to calm their nerves. Other than ordinary ponds, mud bath is a wonderful alternative for the animals, also helping apply a mud sunscreen layer!
Relish or selfish; there's a fine line between them
Confronting climate change requires more than a quick fix. Wild animals withstand the worsening weather through natural wisdom. To some extent, they can adapt to the weather with their natural ability. By contrast, humans who can afford it rely on air-con, regardless of the carbon emissions and the price nature will pay every time an air conditioner is switched on. If the vicious cycle becomes irreversible, no human being can survive the catastrophe.