Surviving without water

How important is water for animals?

Drinking water regularly is necessary for most animals, though there are a few like the Camels and the Sand Cats, who can go without water for long periods of time. They have evolved mechanisms to survive in desert conditions.

While the Sand cat obtains water from its prey, the Camel drinks between 20-100 gallons of water when it can, and this water is stored in its bloodstream. Its red blood cells, unlike that of humans and other mammals (which are circular) are oval in shape.

When a camel drinks water, its red blood cells bloat to twice their size, but don’t burst. Even in times of water scarcity, the oval shape of the cells prevents them from rupturing due to dehydration.

The Koala bears of Australia do not drink water by choice. They eat Eucalyptus leaves, which contain a lot of water, thus fulfilling their need for moisture. Unless forced by a severe drought or a scarcity of Eucalyptus plants, the Koala will not drink water directly. The Spinifex Hopping Mouse found in Australia also manages to survive without water in desert-like conditions.

The Kangaroo Rat of the Death Valley (California, United States) does not drink a drop of water in its entire lifetime, which is about ten years. It saves moisture in every way it can. It feeds on seeds, which it stores in its burrow, letting them absorb as much moisture as they can.

Their kidneys are also efficient in super concentrating urine, so that water loss is minimal. The kidney is made of units called nephrons that filter blood to make urine. The “loop of Henle”- a part of the nephron that is involved in re-absorbing water – is longer in the nephrons of these Kangaroo rats than that of other mammals, helping them to prevent water loss.

Enough Velu”, scolded Mummy. “Come out now, this very minute!”

Velu, the baby elephant, was in no mood to listen. He was still splashing around in the pond, drawing up water in his tiny trunk and squirting it all around. The rest of the elephants had already gone on ahead.

Velu’s father gave him a stern look. “You better come out this very minute, young man”, he said, “or no sugarcane sticks for you!”

Velu’s elder brother, Kuttan, merrily raised his trunk and stuck his tongue out at him, as if to say he would eat Velu’s share of sugarcane as well. Velu was alarmed and pouted at Kuttan.

“Wait, I am coming”, he said hurriedly, as his family joined the herd and started walking away.

Velu was a spirited and cute little elephant, who was the youngest in his herd. Everyone liked him because he was smart and intelligent, and endeared himself to a new person in no time. Being an elephant living in the lush green land of Kerala, it was no surprise that he loved to frolic in the water. But Velu liked to be in the water all the time. He spent more time than anyone else in the pond, and often wasted a lot of water just in play. That morning, Velu had already spent two hours in the pond, but wanted to remain there even longer. But his father’s threat made him look up, and half-heartedly, he got out of the water, and solemnly joined his herd.

“You shouldn’t even be allowed to get into the pond”, said his mother in an exasperated voice. “Once you get in, you don’t come out! You waste half the water in throwing it around on land. The fishes were complaining about you yesterday. They said they are worried that there wouldn’t be a pond left for them!”

Velu giggled. “Oh Ma… I’m not such a baby that you think I am”, he said. “We have an entire herd, with the biggest elephants in the land. They have been using the pond for ages now, and the pond is still there! How can a baby elephant like me make so much of a difference?”

“But the fact is, that you do waste a lot of water”, said his father. “When we have a resource, let’s use it wisely. After all, we cannot live without water. No animal in this world can.”

“Well, then I shall become like your friend, the Camel”, said Velu. “I will start carrying water around in my hump.” And he did an imitation of poor Mr. Camel lumbering along slowly. Kuttan giggled in delight and raised his trunk in approval.

“Stop being so mean, kids”, said their father disapprovingly. “It’s wrong to make fun of someone like that. Do you know how much he has to struggle, and how many days he has to go without water in the desert? You boys aren’t going to learn a lesson this way. I should ask Mr. Camel to give you both a lecture.”

“He just says that”, whispered Kuttan to Velu, reassuring him. “I don’t think he really means it.”

So a few days later, when Velu found Mr. Camel at his home, he was quite surprised. But what puzzled him more was how Mr. Camel had managed to come so quickly from the deserts of Saudi Arabia.

“Ah, there you are, Velu. Kefhaaleki? How are you?” said the Camel enthusiastically.

“I am fine, Uncle, thank you”, said Velu, a little apprehensive about what was to come.

“Your father called me here so that I could give you a lecture”, he whispered and winked, as if it was a joke between them.

Velu sighed. He prepared himself for a long class on being a sensible elephant who would not waste water. Instead, the camel asked him, “Would you like to come with me to Saudi Arabia?” Velu stared at the Camel open-mouthed. “Bbbb..but how will we go?” stammered Velu.

The Camel winked again. “I have a secret.” Saying this, he drew out a big red carpet with pretty tassels at the corners. As soon as the Camel spread it out, the carpet seemed to get a life of its own. It zoomed around them, and then floated down and hovered a foot above the ground near Velu. “This will take us to Saudi Arabia in no time!”

Velu was awe-struck. This had to be the magic flying carpet that he had heard about in the stories of Arabian nights!

“Come now, hop on!” cried the Camel.

Velu jumped onto the carpet along with the Camel, and it zoomed off into the skies. They landed on the deserts of Saudi Arabia soon enough. All around was a vast expanse of sand, with not a drop of water anywhere. The sun beat down on them hard, and soon enough, Velu was thirsty. But the camels were coolly walking around, not in the least bothered!

“Uncle, how do you manage to live here? There isn’t any water around! Do your humps really store water?” cried Velu in distress.

“Our humps store fat, not water”, said the Camel. “When we do get water, we drink as much as we can, and this excess water is stored in our blood.”

The camel then pointed to another animal, which looked very much like the cats back home, but was the colour of sand. “See those Sand cats? They’re desert animals too, like us, and can go without water for a long period of time. But eventually, we all need to drink water.”

Velu nodded in wonder. The Camels hardly got water to drink, forget playing with it! The Camel seemed to sense his thoughts, and smiled. “Let’s go to Australia now”, he said. “There’s someone you should meet.”

They zoomed off to Australia on the magic carpet, and landed in a forest. But funnily, all the trees were the same- Eucalyptus trees!

Velu spotted a small bear like creature munching on some leaves. “What animal is that?” he asked. “That’s the Koala bear”, said the Camel. “He does not drink water by choice, because the Eucalyptus leaves that he eats contain enough water to keep him from getting thirsty. So unless there is a really bad drought or something, he won’t drink water at all.”

Velu wondered if he could eat the Eucalyptus leaves too. He broke a few, and tried eating them. But he didn’t like the taste much. He decided he wouldn’t eat the Eucalyptus leaves unless all the water in Kerala got over!

They got on the carpet again. Velu thought they were going back to Kerala, but they landed elsewhere. “We are in Death Valley, in California, United States”, the Camel announced, “And meet my friend, the Kangaroo rat, who never drinks water in his lifetime.”

A small rodent emerged from a burrow. It had long, powerful hind legs, on which it stood and hopped around, just like the Kangaroo.

“Do you eat eucalyptus leaves too?” asked Velu.

“No, we eat seeds”, replied the Kangaroo Rat. “But our bodies are designed to retain moisture in every possible way. Our kidneys make urine that is 17 times more concentrated than blood, by drawing back into the body as much excess water as it can.”

The Camel took Velu back home after that. Nobody knew where he had gone. But Velu had returned a wiser and more responsible elephant who knew the value of water.

By:Sneha Verghese is a research scholar in Journalism at Osmania University, Hyderabad. Also a post-graduate in biotechnology, she loves teaching and writing stories for kids to explain scientific concepts.