When does a forest become petrified?

A forest  becomes petrified or turned to stone under certain conditions through the action over the centuries of water containing large quantities of minerals. Tree trunks buried ages ago under mud , sand or volcanic ash have been gradually transformed as water seeped into the empty cells of the decayed wood, filling them with mineral matter and preserving every detail of the original structure.

Petrified forest have been found in many parts of North and South America , dating from different geological, periods and containing stone replicas of the trees that grew in these eras. The most famous of these forests is the petrified forest National park in north Arizona, in the United states. There thousands of stone trunks and logs have been exposed to view through the rain washing away the soil in which they were buried. Although now composed of a mineral called silica, the original details of the trees can be studied through a microscope. Some of the trunks are up to 80 feet long and three to four feet in diameter. They are the fossils of cone- bearing trees belonging to Triassic times, the age of the dinosaurs, and are more than 150million years old.

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Why is grass green?

The green colour is green and in most other plants – comes from chloroplast within the cells, each of which contains four different colours or pigments. These are chlorophyll  a. which is the strongest and is blue green; chlorophyll b. which is yellow green ; xantophyll , which is yellow;  and carotene, which is orange and gives carrots their bright colour.

Grass goes from light green in early spring to dark green and brown in summer and autumn because the amount of each pigment changes , like the paint on a palette, to mix new colours.   

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Where would you find cowrie shells?

Cowrie Shells

Cowrie shells are widely distributed and possibly the favourites among shell collectors because of their polished enamel like surfaces and their beautiful coloured patters. The cowrie appears In all the warmer areas of the globe. But the great cowries , the tiger cowrie and the orange cowries are natives of tropical regions. They crawl slowly, browsing on weeds, and are shy creatures  remaining hidden during the day in crevices or under rocks.

The best known and most popular is the tiger cowrie. The shell grows about four inches long and it is covered with spots. It was used by 18^th century silversmiths to make shell snuff- boxes and in Italy for burnishing paper and ironing lace. The shells were often distributed in Europe by sailors and gypsies.

Orange cowries at one time sold for large sums on the market. In Fiji and the New Hebrides in the pacific they are still worn as badges of rank by the chiefs.

The money cowrie is a small oval shell, flat and white underneath with thick yellowish white edges and a pale lemon upper surface. It is found in enormous quantities in the Pacific, from the Moluccas eastward. Large fortunes were at one time made by European traders who transported shells to the west coast of Africa and exchanged them for ivory, gold and slaves. A slave would be worth anything from 20000 to 50000 shells. In 1849 money cowries weighing 240 tons were imported in to the English port of Liverpool.

A man at Cuttack in Orissa, India pad for the erection of his bungalow entirely in cowries.The building cost him pounds 400 which in cowries amounted to 16000000 shells. The common method of handling the cowries was by threading them on a string, 40 cowries to one string.

Among the cowries the rarest is Cypreae leucedon. Only two known examples of the pale brown, creamy spotted shell exist. One is in the British Museum, the other is in the Harvard University Museum. More than 190 species of cowrie shell are known to collectors. Some species are used as charms against evil spirits.          

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When do drones die?

The male bee or drone, dies when there is no more nectar available from the fields. The reason for this is that when the worker bees can no longer collect nectar for the hive, the production of honey stops. Deprived of their food the drones rapidly grow weak and are carried from the hive by the workers to die.

The drone takes 24 days to develop from the egg to fully grown male and may live as an adult for several months. Its only function in the bee’s community is as a potential male for the queen. 

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Why do some plants capture insects?

Some plants capture insects and other tiny animals and use them as food . They do not devour their prey  by chewing but decompose them in a mixture of enzymes. The pitcher plant attracts an insect to its large showy leaf by means of sweet smelling nectar. The leaf has a treacherous lip which precipitates the unwary victim in to a deep hollow pitcher full of digestive “broth” , which soon decomposes its body. Other plants like the venus’s fly trap, snap their  leaves shut on their  prey  as it prowls about the trigger hairs glistening with drops of nectar. The sundews secrete a sticky fluid.                           

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