As what geographers have estimated, about twenty percent of the earth's surface is..........they need to spend a large part of their time flying in search of waterholes.

As what geographers have estimated, about twenty percent of the earth's surface is occupied by deserts. A majority of us view deserts as one unique kind of landscape -- areas with little or no rainfalls.

In actual fact, there are differences between the deserts, though in varying degrees. While it is common for laymen like us to see deserts as rocky or covered with gravel or pebbles, there are some where large sand dunes inhabit. Despite the fact that rainfall is minimal, temperatures do change in deserts, ranging from seasonal ones to daily changes where extreme hotness and coldness are experienced in the day and night.

Unfavorable conditions in the deserts, especially the lack of water, have discouraged many living things from inhabiting these landscapes. Nevertheless, there are exceptionally surviving ones which through their superb tactics, have managed to live through and are still going strong. One such kind is the specialist annual plants which overcome seasonal temperature changes with their extremely short, active life cycles. In events of sudden rain, the plant seeds pullulate and grow very quickly to make full use of the rain water. Their flowers bloom and set seeds that ripen quickly in the hot sun too. Once the water runs dry, the mother plant dies, leaving behind the drought-resistant seeds, waiting patiently for the next rainy season to arrive.

The Cacti, a native in American deserts, adapts to the dry surroundings by having unique body structures. The plant has swollen stems to help store water that carries it through months. By having sharp pines instead of leaves, water loss through respiration is minimized. Besides, these pointed pines also help the plant ward off grazing animals, thus enhancing its survival period.

Besides plants, there are also animals with distinct surviving tactics in deserts too. For instance, Skinks ( desert lizards ) metabolize stored fats in their bulbous tails, producing water to supplement their needs, just like what camels do with the stored food in their humps during long journeys through deserts. Antelopes like the addax, have very low water needs and hence are able to tolerate the conditions in deserts, extracting moisture from the food they eat.

Finally, there are the sandgrouses ( desert birds ) which do not have special features to overcome the drought-like nature in deserts. Hence, to survive in these hot, dry deserts, they need to spend a large part of their time flying in search of waterholes.

Summary: Despite the dry conditions in the deserts, some plants and animals still manage to survive there. One of them is the specialist annual plants. Their short life cycles allow them to germinate, grow and produce seeds during short rainy seasons. These seeds are drought-resistant and are able to wait for the next rainy season before starting their life cycles again. The Cacti adapts to the dry weather by having swollen stems for water storage and pine-like leaves to minimize water loss through respiration. Skinks generate water from stored fats in their tails and antelopes which requires very little water, survives in deserts by extracting water from food they eat. Finally, sandgrouse with no adaptive features turn to waterholes constantly for help. 


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