January 9 2018

 
 
HOW DO THEY DRINK WATER?
Rex Burress
 
With water much on the mind of every living thing during these torrid days of summer, I thought about how animals utilize the precious fluid .
 
I had never thought much about how animals drink until I saw an episode showing elephants drinking at a steep waterhole. Have you noticed? They suck water into their trunk and then squirt it into their mouth. The trunk is a nose separate from the mouth!
 
We drink with mostly the aid of gravity in swallowing, but of course we can suck as through a straw or suck milk from a mother's breast. It's the cutest thing ever to see a baby cup its tiny plump liparound a plump nipple and suck in an instinct as old as human beings. No wonder adult men--and women, seek the suck sensation all life long. Kissing, smoking, sipping coffee are habits of the lips.
 
Nearly all mammal babies are suckers because of the mammary gland defining warm-blooded mammals. The suction necessary to move the fluid along, a long haul in the case of a giraffe, has a scientific basis as in Peristalsis--wave-like muscle movements that can move water or food along.
 
If elephants have a unique way of drinking, the giraffe seems most unsuited to take in water. To drink, it must spread its front legs to get its head down to water level, then like a tree drawing water up to leaves and sugars down to the roots, it's all up-and-downhill!
 
Trees are much involved in water, the roots drinking as it were, from Earth's sweet flowing breast. It seems impossible that trees can force water against gravity a couple hundred feet upward to the topmost leaves and retain the rigidity to keep it standing! Transpiration, the evaporation of water in the leaves, causes a 'transpiration pull,' as the evaporative loss of water creates a suction force that pulls water up through the xylem vessels.
 
Turgor pressure provided by osmosis helps in the process by pushing outward on the cell walls and helping the plant to retain its shape. These things have been studied and there's a name for every function, just as we have taxonomy labels for every item of nature. In the understanding of nature, many naturalists put more emphasis on environmental habitat than names of animals, but understanding begins with knowing the name. “The beginning of wisdom is to call things by their right names.” --Chinese Proverb.
 
Have you watched closely how your dog, or a wolf, or any dog-family member drinks? The tongue is folded at the end to form a little scoop as it laps up fluid. A cat drops the tongue straight and more delicately makes the transfer. It happens fast but it's mostly the tongue that's involved. Most ruminants--livestock, horses, cows--use the tongue in a similar way, rather sucking and lapping.
 
Maybe you have noticed birds drinking, and most of the song bird species dip and lift their beaks to let water run down the throat with gravity, much like people lifting the glass to let it pour down the throat. But the pigeon family stick their bills in the water and suck, siphoning as much as 15% of their body weight per day, an unusual amount among birds. Swallows in particular, take a drink on the wing, sailing low and utilizing the lower bill to skim up a drink.
 
Of course, hummingbirds do it quite differently, thrusting the long tongue and long bill into the flower's throat and sipping the nectar. Some species of flowers grow special long tubular blossoms to accommodate certain hummingbirds with the ultimate goal of attracting animals most suited to help them with pollination. “Nature moves in mysterious ways her wonders to perform.”
 
“The frog does not drink up the pond in which it lives.” --Chinese Proverb
“Water is the driving force of all nature.” --Leonardo deVinci
“If there is magic on this planet, it is contained in water.” --Loren Eiseley