Severe lack of vegetations, rainfall and infertile ground are common factors for all
deserts on earth. When we talk about deserts we mostly think about the terribly hot sea of
sands with no life around. But not all deserts are full of hot sands. There are cold
deserts as well with snow covered land stretching for hundreds of miles with no
vegetations or apparent sign of life, save a few stray patches of thorny plants.
|These are seen around the tropical belts in
Africa, Middle East, part of Indian subcontinent, southern parts of North America, and
parts of north Australia. With too little rain to keep the covering plants alive makes
life in deserts real tough. Those who survive do so by resorting to some strange adaptive
techniques. While some deserts are sandy, some consist of stones and rocks with stray
pockets of sand. Some are plains; while some are ridged by steep-sided rocks and
mountains. Though most are fiery hot at daytime and cools off after sunset, there are few
where icy north wind blows all through. Mostly short thorny trees and bushes known as
cactus, and hay like weeds sprout at some places in the sand.
Animals and birds find food and cope with heat and drought in various ways. All their
bodies have a built in mechanism to procure and retain the moisture needed for survival
from the harsh surroundings. Deserts are infested with a wide variety of insects, lizards,
snakes and small creatures.
|Among the smallies are tiny crustaceans,
like woodlice with humped backs that shade their bodies from the sun.
|When rain fills hollows, tiny tadpole-like Triops as
also some frogs hatch from eggs laid long ago. They lay eggs. But their life span
stretches about two weeks after which the pools dry up and they too die. Only their eggs survive to be self hatched in the sand.
The desert butterflies and moths also pass the dry season
as pupae and are woken up by the rains. They grow up, lay eggs and die. Everything is
complete by the time the plants dry up fully. Desert locusts are huge grasshoppers. They
sometimes fly in dense clouds seeking leaves to eat.
Certain beetles survive 17 years of drought by consuming only dry plants and
dung. Among other insects are the scorpions and spiders. Scorpions spend hot days in
crevices or holes dug under stones, among tree roots or by dry dry streams of rivers. They
seize insects that stray in. At night these hunters emerge for making a kill for their
The sun spiders or
camel spiders also seize insects with their pincers. They have huge jaws but lack the
poison with which most other spiders kill their prey.
The bold wolf spiders hunt in the open. Keen-eyed jumping spiders detect and creep up on
their prey from a distance. Then pounce on them like cats.
The desert reptiles feed on the insects and spiders. The
reptiles' waterproof skins retain body moisture and bodies release little water as waste.
But they prefer hunting at night, or at dawn and dusk. Because long exposure in the hot
tropical sun could kill the reptiles. Most lizards including the collared lizard prey on
insects. The chuckwall wedges and spiny tailed lizards feed on plants. These have no
poison. But the orange and black Gila monster relies on poisonous fangs and bright warning
colors for thier defense.
Slithering over hot sand is a problem for snakes. Some flow along in looping movement,
lifting part of their body into the air. Thus while moving they do not sink in the sand
and keeps part of its body off the hot ground. The horned viper and sidewinder rattlesnake
move in this way. Both quickly burrow into cool sand when the sun becomes too hot. Among
others, rattlesnakes, vipers and some cobras flourish in deserts. The speckled,
multicolored coral snakes eat other snakes and lizards.
Desert tortoises are seen in the American desert. By the time the sun rides high,
tortoises have retreated to cool, dark holes in the ground. And come out only when sun
Most small mammals are rat-sized rodents and include the similar-looking jerboasof Africa and kangaroo
rats of North America. Asleep underground, ground squirrels survive hot desert
||Most desert rodents including kangaroo-rats,
pack rats, pocket mice and white footed mice eat seeds or other dry foods. But African sand rats munch salty succulent plants.
Hunting the rodents are carnivores such as foxes, jackals, coyotes and skunks. The African
fennec foxes get all the moisture they need from juices in their victims' bodies.
Big ears serve as radiators that help to prevent the
foxes overheating. The jackrabbit's giant ears also help in the same way.
Among the larger mammals, camels are called the 'ship of the desert' for their ability to
go without water for weeks together. The hump on the back stores the extra fat so they may
do without food and water for a long time. They lose little water as urine and start
sweating only when the temperature exceeds 40 C. Their eyes are heavily lidded so as to
protect them from the blinding storms. The feet are heavily padded to stand the hot sand.
All these have equipped the camel to travel long through the desert.
|Wild asses too can live a long time without
water. Oryxes usually get what water they need from plants and dew. Their long thin limbs
help them to radiate spare heat from the body.
back to land animals main|cold desert animals