Why the cotton plant is called Daughter of the Sun?


               The ancients called the cotton plant the ‘Daughter of the Sun’. This was because it was only under the powerful rays of the sun that the plant would grow and flourish. The hotter the sun, the whiter and stronger would be the fibres produced. Ideal conditions for cotton growing require sunlight, heat and rain. Due to these reasons cotton is mostly grown in hot and tropical places all over the world.



               The plant grows upto 2 metres and produces seed pods or bolls which contain about 30 seeds each covered with downy hairs. As the bolls ripen, they grow and then burst open to reveal a mass of fibres.



               The cotton fibres provide the most common material used in clothing. The cotton industry is the greatest of the textile industries and gives work to millions of people all over the world. Cotton fibre is the only fibre that does not have to be softened by soaking or subjected to any other expensive treatment. It just requires to be freed from seeds before being used. However, cotton disease (byssinois) are caused by cotton dust which affects the lungs of those working in industries.



               There are about 20 species of cotton plants, only four of which are cultivated. The People’s Republic of China is the leading producer of cotton, followed by the United States. Apart from these countries cotton is also grown in large quantities in India, Peru, Russia, Brazil, Egypt, and Pakistan and in other tropical and sub-tropical regions of the world. Cotton fibres vary in length from less than 2cm to 4 cm or more. However, short and medium length fibres account for about 90% of world production. Cotton fibres are used in textiles, rugs, sheets, bandages and book binding. Cotton seed can be squeezed for oil used in margarine, salad oil and mellorine. This is also used in manufacturing of cosmetics, paints and soaps. The seeds are then processed into cattle cake and fertilizer.



 


Which fish spits at insects?


               Fishes are the most numerous among vertebrates and their species number more than 30,000 which is more than all the other backboned animals put together. Each group has its own way of gathering food. The archer fish is such a fish which can shoot down insects from overhanging vegetation with water pellets. Its aim is quite accurate and it can easily dislodge a fly or a beetle about four feet away, so that it falls into water. The archer fish then dashes on the insect and eats it up.



               It is interesting to find out how the fish is able to project drops of water accurately over such a distance. The roof of its mouth forms a long groove. If the fish suddenly closes its gill covers, water is forced from the gill chamber into the mouth. At the same time the tongue is raised so the grooves become a long tube from which water squirts in a line of drops.



               Archer fish is a fresh water fish and belongs to the family Toxobidae. It is found in India and Indonesia. It got its name from the way it captures its food. Archer fish can also live in sea water. Toxotese jaculator is the most commonly known fish of this family. Its length can be upto 18 cm. Five groups of this fish have been studied. These fishes generally feed on insects. 


How do plants protect themselves from frost?

            There are over 350,000 kinds of plants in the world. All these continue to struggle to survive against storms, rains, sun and snow. There are some which die due to cold in winters, although before dying their seeds are spread on the ground so that in the autumn they can give birth to new plants. However, there are some plants which are able to protect themselves against winter.



            These plants are able to protect themselves against winter frost by a special method. They spread their leaves and flatten them against the ground. The warmth in the soil enters their leaves and the plant is protected. Some other plants like myrtle and heather allow their upper parts to die but their stem remains alive. Stems act as storage organs, both above and below the ground. These produce buds and thus restore their species. Many plants hide themselves under the soil to escape from the cold, these include tubers, bulbs and roots which store their food according to their need. When summer comes they push out green leaves and new buds.



            Sometimes artificial methods are used to protect plants from frost, e.g. oil heaters called smudge pots are used in the region where citrus fruits are grown. In some places large fans are used to keep the cold air moving so that frost is not able to get deposited on the fruit trees.




How do different animals move?


There are millions of animals found on earth that moves about in hundreds of different ways. Some walk or run, while some others jump, crawl, swim, fly or glide.



The various types of movements of different land animals are as follows.



(a) Walking: Four legged animals walk by moving the fore-leg of one side together with the hind-leg of the other. This is the basic movement of animals with limbs. Insects which have six legs move fore and hind legs of one side with the middle leg of the other side so that the body is always supported firmly by the other three legs.



(b) Pacing or ambling: Elephants, giraffes, camels and a few other animals move both legs of the same side simultaneously.



(c) Trotting: This type of movement is characteristic of horses, cattle and many other four-legged animals. It requires a little effort and can continue for long distances.



(d) Galloping: In this type of movement all the four feet remain in air for some distance. This is very tiring. Horses and cheetahs can gallop at a high speed.



(e) Jumping: Kangaroos, frogs, grass hoppers, and fleas are excellent jumpers. They can jump to different heights.



(f) Contracting and expanding: Creatures like earthworm, slugs and snails move by passing a wave of contraction along their body. Among these animals waves of muscular contraction and expansion pass along the body from front to back.



(g) Crawling: A snake moves through muscle contraction and relaxation. It moves by wriggling along the ground or swinging its body in loops. It also crawls with the help of the overlapping scales on its belly with which it hitches itself on a rough surface effectively.



(h) Undulatory walking: This type of motion is peculiar to lizards. A lizard uses its legs for walking in the same way as a crawling baby. But because its belly rests on the ground, it undulate its body as well. Crocodiles, newts and salamanders also walk like this. 


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How do animals release their tension?

          Sometimes animals are caught in such a situation that they can neither run away from their enemies nor fight with them. In such situations they become very tense. Different animals react differently to get rid of their tense moments.



          To understand this mechanism of relieving tension let us take an example of a school boy who has done some wrong and is facing his teacher. He feels guilty and perhaps frightened also. He cannot run away or fight. He is caught in a tense situation, and somehow he must come out of it. So he does something looking incoherent like scratching his head or blowing his nose to fight off his tension. Such actions help him in relieving his tension.



          For instances, when a mouse is cornered by a cat and cannot escape, it will sit up and scratch its face with its forelegs. A bird which is frightened of a cat will make pecking movements (when birds start striking with their beaks). A monkey relieves its tension by uttering different sounds. Similarly, dogs relieve their tension by barking. All these actions are meant for getting rid of tension. These are called displacement actions. Animals act in such ways to regain their normal state. Sometimes they can cause harm to others. All these actions are their reflex actions. These actions help animals to survive.



          To demonstrate the reflex action a Russian scientist Ivan Pavlov carried out a famous experiment with some dogs. In this experiment, he showed some food to the dogs. Due to this their mouths got watered. At the same time he rang a bell. He repeated this for a few days and then began to ring the bell without showing the food. The dogs became so used to the association of the sound of the bell and the sight of the food that their mouths still watered even when food was not shown. This is called conditioned reflex action. This happens involuntarily when animals are trained for some purpose. They start doing these actions automatically. In a similar manner people learn studying and talking simultaneously.




How do living beings adapt to their environment?

               Adaptation is a biological term which means the process by which all living things change or adapt to new and unfavourable conditions for their survival. Thus human beings, plants and all other living things adapt to their environment for survival. 





               In plants, take the example of the oak tree. Since it grows in a moist climate, its green leaves require much water to carry on the process of photosynthesis. On the other hand, since the desert cactus cannot afford large leaves that would lose more water, its leaves are reduced to spines that grow out of a waterproof stem. To come to some animals, the beaks of birds are again adapted to particular ways of feeding. For example, preying birds like woodpeckers and kingfishers have sharp strong beaks to tear their prey.



               There are two kinds of adaptations: individual adaptation and group adaptation. In individual adaptation an individual adapts himself to new conditions automatically in his lifetime. Group adaptation refers to adaptation by a group. It is a slow process and occurs over many generations. For instance if a man’s job is such that he has to work during night time he would have to adapt to such a routine gradually. To begin with, he may have some difficulty in sleeping during the day but when adapted to the changing requirements after sometime, he would sleep easily. 


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Which animal can see with its eyes closed?


               There are about 2000 lizard species in the world including chameleon, iguana and skinks. Skinks are one of the two largest families of lizards. They are found in all the tropical countries but they are most abundant in Africa, East Indies and Australia. They belong to the Cincidae family. There are about 700 species of skinks. Skinks are shy and retiring, so people are mostly ignorant of them.



               Skinks have very thin, small legs. They have a smooth skin and a small pointed head. They can crawl over the uneven surface. Unlike snakes, thin jaw bones are fixed. Most of them are ground dwellers.



               A very strange characteristic of skinks is that they can see with their eyes closed. While burrowing or eating insects they close their eyes. They have a permanent, transparent eye lid cover over their eyes with which they close their eyes. As this lid is transparent, skinks can see with their eyes closed.



               Another characteristic feature of skinks is that they can squeeze their size during the squirming movement through the soil. In some skinks the feet look ridiculously small when compared to their body size and in others they get disappeared altogether.



               Some skinks lay eggs, others bear live young. These skinks include the tiny three-toed skinks of southern Europe and north Western Africa. They grow upto 40 cm long of which half is tail. Australian skink stores fat in its tail and looks the same from both ends. It feeds on fruits, insects as well as small animals.



               Now the question arises why skinks close their eyes? When skinks move in the dust, the dust can enter its eyes. So to protect against dust and sand it closes its eyes.



 


Which is the largest seabird?


               Albatross is the largest flying sea-bird. It can have a wingspan of 3.15 m (10 ft 4 in.) at full stretch. It belongs to Diomedeidae family and is found mainly in south of the equator. It has a long, heavy beak and long narrow wings which allow it to soar on the wind seemingly without effort for hours. Its body is about 1.2 metres long.



               There are more than a dozen species of Albatross. It experiences certain difficulty in taking off. It needs some wind and must run along the ground or paddle with its feet across the water for a long time before it can soar.



                Like other oceanic birds, albatross also drinks sea water. Although it normally lives on squid, it is attracted to ship’s garbage. It comes ashore only to breed in colonies on islands. It lays a single large white egg on ground in the open, which is incubated alternatively by the male and female parent. The growth of a young albatross is very slow. It attains flight plumage in 3 to 10 months, and then spends the next 5 to 10 years at sea, learning navigation and feeding techniques. Albatrosses live long and are among the few birds that die of old age.



               However, among the sea birds which use wings for swimming and not for flying, the largest is the Emperor Penguin of Antarctica. Standing over one metre high and weighing 40 kg, the Plum Emperor lives in the most remote shores of the great ice-bound continent.



               The largest ever recorded specimen of albatross was a very old male with a wingspan of 3.63 m. (11 ft. 11 inch). This was caught by the members of the Antarctic research ship in the Tasman Sea on 18 September, 1965.


Where do crabs climb trees?


               It is established by the scientists that the most successful free living kinds of animals judged by the number of species and standing stocks of living substance, have come from marine surroundings.



               In 1964, Sir Vernon Wigglesword had suggested that, at first these animals might have lived along the shore lines and later moved in two directions. A part colonized the open sea and ocean deeps to give rise to crabs, crustacea etc and the other part moved to land areas.



               Crabs are mainly marine animals - although some live in fresh water or land. They are ten-legged alert carnivores that act as scavengers. There are many species of crabs worldwide; such as European crabs, shore crabs, edible crabs, fiddler crabs, river crabs, common hermit crabs and robber crabs.



               Among all these, robber crabs or commonly known as ‘coconut crabs’ are well adapted for living on land, although their larvae first live in the sea. But if an adult robber crab is left under water beyond 24 hours, it will be drowned ultimately. These are the crabs which can climb trees.



               The robber crab (Birgus Latro) is an extremely large land crab of South-West Pacific and Indian Ocean. Adults of robber crabs are about one metre long (40 inches) and weigh about 15-17 kilograms. A robber crab uses two large chelae or pincers to pound or chip coconuts to eat the soft white portion of the coconut. They climb coconut trees to detach coconuts from tree tops through they are quite unable to get inside a coconut on their own. They apparently eat coconut meat already broken into the ground by other means.



               The colour of a grown crab ranges from light violet to brown and deep purple with black strips on their legs. The female lays her eggs in sea. In larval state, it lives in water, feeding on small organisms. After about a month when it is grown to intermediate stage, it leaves water to live in a shell for 3-4 weeks. It then discards the shell and buries itself in moist sands, and transforms into an adult robber crab. Its meat is a local delicacy. 


Why do dogs pant in summer?

               A dog, like a cow, an elephant, or a man, is a mammal. All mammals are warm blooded, or homothermic animals. In the animal world only mammals and birds are warm-blooded creatures. The rest of the animals are cold-blooded or ectothermic. A warm-blooded animal has a relatively constant body temperature, while the temperature of cold-blooded animals changes according to surroundings. 



               Heat is being constantly produced in our body. A part of it escapes through our skin. We have sweat glands under our skin and sweat comes out through small pores in it. When sweat evaporates, it absorbs heat from the body producing a cooling effect.



               Unfortunately, not all mammals can use this method to get rid of their body heat.



               For example, a dog has few sweat glands and, therefore, cannot sweat like us. Similarly, tigers, lions, cheetahs, etc. cannot sweat much. Birds and rats also cannot sweat.



               A dog has a different mechanism to control its body temperature. It does so by hanging its tongue out. When a dog pants, it takes in air through the nose and gives out air through the mouth. The saliva in its mouth evaporates. Evaporation of saliva produces a cooling effect and the dog feels comfortable. This habit of panting is simply a natural urge of a dog to control its body temperature in accordance with its surroundings.



               An elephant also maintains its body temperature in a very interesting manner. Its skin is very thick and not much heat can escape through it. However, the skin on its ears is much thinner. The elephant, therefore, tries to get rid of the body heat through its ears. Nature has given the elephant very large ears which it can flap in a bid to lose heat. The skin of our ears being quite thin, the ears feel cold on a winter day.



 


Why do flowers of Raat Ki Rani bloom only at night?


               Many animals and creatures rest during the day but become active at night. Similarly there are many plants which bloom at night only. Such plants are called night blooming plants. The flowers of Raat Ki Rani (Queen of the Night) also fall in the same category. Many night flowering plants belong to the honeysuckle and nightshade families. Do you know why do flowers of Queen of the Night bloom at night only? It is quite often in the case of night flowering plants that they resort to the use of scent, thereby attracting high-flying insects and moths.



               When these insects sit on the flower, a few pollen grains get stuck to their tiny feet and wings. When the same insects go to other flowers of the same variety, the pollen grains are deposited on the flower. This process helps pollination, without which a flower cannot mature into a fruit. Thus we can say that flowers of the Queen of the Night bloom at night to attract those insects which help the process of pollination. Flowers produce fruits and fruits produce seeds. The seeds are responsible for producing new plants.



               Most of the flowers blooming at night are those which cannot bear high temperature and light of the day time. Flowers of Raat Ki Rani also avoid extremes of temperature and daylight by blooming at night.



               There is one more fact about the night blooming flowers. Such flowers do not have attractive and pleasing colours as these colours are not visible in the darkness of night. Most of the night blooming flowers are white because this colour is easily visible in the darkness of night and quite effective in attracting the insects for pollination. In fact, all white or cream coloured flowers such as night-scented stock are pollinated by night-flying moths which are attracted by strong perfumes of the flowers.



               Thus we see that flowers of Raat Ki Rani are not capable of withstanding day temperature, usually white in colour and have a delicious fragrance with which they attract insects. 


Does any animal have three eyes?


               Tuatara or Sphenodon punctatus is a strange lizard like animal that has three eyes. It is the only animal in the reptile group which is placed in a separate sub-group rhynchocephalia. Although it resembles lizards, it is truly a precious living fossil, since this reptile order goes back to the time of the dinosaurs. Tuatara is found only on the islets of New Zealand. A full grown male weighs upto 1 kg but females weigh only half that of a mature male of similar age.



               The strange thing about this animal is that it has three eyes. The cone like third eye is called the pineal eye. This eye is situated in a hole between the head and brain. It has an eyelid over the third eye which closes horizontally. One can’t say anything about the use of the third eye of this animal but certainly it had some use for these prehistoric animals.



               This animal is active at night. Generally it lives in burrows often in company with sea birds. It is a very shy and retiring animal. It eats insects, other animals like frogs, rats and eggs of birds also.



               The average life of a Tuatara usually does not exceed 77 years, but some Tuataras may live upto 100 years. Male Tuataras are unusual in the sense that they have no copulatory organ; their matings are accomplished by cloacal apposition. Female Tuatara lays 8 to 15 eggs in the spring, at some distance from its burrow. Hatching of eggs occurs in the next summer which means that hatching takes about one year of time.



               It is a unique animal and represents a whole vanished order of reptiles. All other species except this one became extinct and only this particular type has lived unchanged till the present day. In captivity it can live upto fifty years only.



               This strange animal is now facing extinction. The government of New Zealand has been making great efforts to prevent the extinction of this animal.



 


Where is cocoa grown?


               Cocoa originated in Central and South America. It is said that Christopher Columbus introduced cocoa beans in Europe in 1502. The cocoa seeds however were first commercially planted in 1879 in Ghana. Upto 1913 Ghana was the leading cocoa producing country in the world. Even today Ghana is the largest cocoa producer. It is believed that several lakhs of people are associated with the production of cocoa in Ghana.



               The cocoa trees grow to a height of about 7 metre. It is an evergreen plant. Twice a year, small, star like, pink and yellow flowers appear on it. After sometime flowers grow into fruits or pods of the shape of an egg which are about 6-10 inches long and 3-4 inches thick. These pods take about six months to ripe.



               Equatorial regions are most suitable for growing cocoa trees. It needs constant moisture and in some countries watering is also necessary. Regions having a rain fall of 50-100 mm are most suitable for these plants.



               Generally there are two crops of cocoa —first crop from October to March and other crop from May to August. When cocoa tree is five years old it starts bearing fruits. The ripe fruits are cut with sharp knives from branches. Women and girls usually collect these in baskets and take it to another place where cocoa beans are scooped out from these pods. After this, beans are subjected to fermentation. For this purpose, beans are put into perforated boxes and heated at constant temperature. By this process which takes about six days, impurities are removed to bring out the flavour.



               Cocoa is used in many eatables. But it is mainly used in preparing chocolates. Chocolate powder is made from dry cocoa seeds. Cocoa butter is made by extracting fats from cocoa beans. In ice cream it is used for flavour. It is also used in the manufacture of some medicines. 


Which are the largest and smallest flowers?

               In the world of nature we see a great variety of flowers. We have virtually flowers of every conceivable colour. Some are so perfectly symmetrical with vibrant colours that their beauty attracts us immediately. Some others are shaped like insects or lizards.



               Most flowers have fragrance. However, flowers are not just decorative creations but play a great productive role also. They produce fruits by the process of pollination and the fruits in turn produce seeds.



               In this great world of flowers do you know which the biggest flower is and which is the smallest? 





           



 



                The biggest flower in the world is Rafflesia arnoldii. It is found in the Sumatran Jungle and can have a diameter of over a yard. It is about 0.75 inch thick and weighs about 7 kg. The flower can grow to 91 cm. (3 ft) wide. It blooms for five to seven days. It is reddish or orange brown in colour. It has an unpleasant odour which is attractive to flies. These flies carry out the pollination process. Rafflesia is a parasitic plant and feeds on the sap of trees. It does not have any leaves. 



 



 



 





 



 



 



 



 



                The largest recorded chrysanthemum flower was cultivated by Francois Santini of Indre - et - lorie, France. This giant flower was 2.5 m (8ft. 2 inch) tall and had 4041 blooms. 



 



 



 



 



 



 



 


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Which is the most beautiful reptile?

               There are about 5000 species of reptiles. These include lizards, tortoises, crocodiles, etc. Most of the species of reptiles live on and but there are some which live in water. Their length varies from 5 cm to 10 metres. The smallest lizard is found in tropical regions while python is the largest snake. All reptiles are cold-blooded animals. Although they are found everywhere on earth but they are most common in tropical regions. Do you know among all reptiles which are the most beautiful?



               The European Green Lizard is the most beautiful reptile. It is the second largest lizard to be found in Europe — the male reaching a length of 16 inches, its tail alone being 10 inches long. 





               Green lizards are found throughout Europe although they do not have natural habitats in Great Britain. Attempts have been made to establish colonies but it is believed that the climate there is not really warm enough for their survival. They are most commonly seen in Mediterranean countries, basking on the rocks and among the ruins. There is also another kind of lizard known as Arizona Lizard. It has a bright black and white colour in its body.



               Green lizards are sold in petshops. Their elegant reptile shape and attractive colouring attracts people to buy them. It is not difficult to keep them as pets. They only need proper care. They feed on insects, spiders and worms.



               Most lizards are harmless. The only lizards with a poisonous bite are the Gila Monsters with black and white marks on their body.