Showing posts with label Old. Show all posts
Showing posts with label Old. Show all posts

Friday, November 15, 2013

Indian scientific history

aryabhatta
Aryabhatta I earth’s rotational time
At the age of 23, Aryabhatta I judiciously noted down his observations and calculations for a mathematical system to figure out the workings of the universe for his now famous work Aryabhatiyam. The book, his only surviving treatise on mathematical astronomy, states that the Earth was spherical in shape, rotates on its axis and like the remaining planets, revolves around the Sun in an elliptical orbit. All this, 1500 years and 1000 years before Copernicus and Galileo! He also calculated that the Earth takes 23 hours 56 minutes and 4.01 seconds to complete one rotation, which coincides with the modern value of 23:56:4.091.
Brahmagupt a rules for zero
While Bhaskara I maybe credited with giving zero the symbol it has today and Aryabhatta for introducing zero to the world, it was in fact Brahmagupta who gave zero its exalted status as a number in mathematics. He was the first mathematician to frame the rules of operations. He concluded rather successfully in his book, Brahmasphuta Siddhanta that the addition or subtraction of zero to or from any quantity, negative or positive is always zero, the product of any quantity with zero is zero and that the division of any quantity by zero is infinity.
Bhaskara IFormulated units, tens, hundreds…
He did give the numeral zero its symbol, but Bhaskara’s I probably most important mathematical contribution concerns the representation of numbers in the positional system. Numbers are arranged in columns and have to be read from right to left as units, tens, hundreds, thousands and so on. He has given us an extremely succinct method for writing down even very large numbers.
 Nagarjuna I
Discoverer of alloys
Around 2nd BC, in a laboratory in Nagarjuna Konda, Andhra Pradesh, Nagarjuna I, a Buddhist monk, exclaimed in joy as he discovered the process of alloying. His book, Rasarathnakara, retains notes on the process of extraction of silver, tin and copper from their ores and their purification. They also mention the process of distillation, sublimation, 106 calcination and colouring of metals.
Baudhayana Before Pythagoras
Baudhayana, in his book, the Sulba Sutra, mentions a theorem stating that a rope stretched along the length of the diagonal (hypotenuse) of a rectangle produces an area, which the vertical and horizontal sides make together. Sounds familiar? It is in fact a prelude to a theorem, which would eventually be known as the Pythagoras theorem.
varahamihira
Varahamihira
Mapping the skies Gather around all ye sailors, astronomers, astrologers and star-gazers. A man named Varahamihira gazed at the stars one night as you do and observed that the night sky continuously shifts throughout the year as the Earth orbits the sun. But, “If one were to take a fixed point in time and mark the position of the star on that day every year,” he put forth, “one would notice the sky slowly shifting backwards with each progressing year.” He was the first to mention in his work Pancha Siddhantika that the ayanamsa, or the shifting of the equinox is 50.32 seconds, which remains unchanged till this day. This time period helps us chart and navigate the skies at night or day, learn about our horoscope for the year and keep a track of our favourite constellation.
Bhaskara II
GRAVITY
We don’t know whether an apple fell on Bhaskara II’s head as he was resting underneath the tree or that maybe he fell from the apple tree itself. All we know is that he was the first to conceive and write on the notion of gravity and the effect of its force some 500 years before the proverbial apple fell on Sir Isaac Newton’s head. In his book, Surya Siddhant, Bhaskara II makes a note on the force of gravity: “Objects,” he noted, “fall on earth due to a force of attraction by the Earth. Therefore, the Earth, planets, constellations, moon, and sun are held in orbit due to this attraction.” How do you like them apples?
shushrutha
Sushruta
1st PLASTIC SURGEON
2600 years ago, Sushruta along with his colleagues conducted what could be termed as the first plastic surgery in the world. To reconstruct the amputated noses of his patients, a marked punishment of their crimes, Sushruta would use his technique of forehead flap rhinoplasty, which is repairing the disfigured nose with a flap of skin from the forehead, a practice almost unchanged to this day. Educated in Varanasi, Sushruta pioneered the science of surgery in India. His book, the Sushruta Samhita, is the first classical book of surgery, in which he describes over 120 surgical instruments, 300 surgical procedures and classifies human surgery in eight categories. In case you are wondering about the pain, local anaesthesia was given in the form of medicated wine.
kanada
Kanada
Proponent of Atomic Theory
According to folklore, whilst nibbling on a morsel of food, Kanada threw away the bits after realising that they could not be divided into smaller bites. This incident prompted him to consider that everything in the universe is made up of pramanu (atom), the real entities which are obtained when a matter is divided and subdivided until further division is not possible. Many believe that Kanada was the earliest proponent of the atomic concept in the universe and that the atom was the indestructible particle of matter, long before John Dalton some 2500 years later introduced his Law of Atomic Theory into modern day physics.

Life barier on the western ghats of india

Birds

There are 508 species of birds found in the Western Ghats, out of which 16 species are endemic to the region. The Laughingthrush are amongst the most prolific ones sighted here. The two main species of the Laughingthrush found in the region are the Kerala Laughingthrush and the Black-chinned Laughingthrush; the former found principally in the region south of the Palakkad Gap whereas the population of the latter is confined to the Nilgiri region in the Ghats. Dr P O Nameer of the Centre for Wildlife Studies, Kerala, adds that species differ morphologically and are allopatric in their distribution, meaning that their ranges do not overlap each other ensuring that each species have their distinctive characteristics preserved. “While the two species may share their home in the high altitude regions of the southern Western Ghats, their behavioural activities are different,” he says. The bird calls of the Kerala Laughingthrush consists of high-pitched series of steeply ascending notes ‘pee-koko… pee-koko’ while the Black-chinned resort to making birds calls in ascending and descending sounds of ‘kek’, heard during early morning and afternoon periods. Another distinction between the species is their diet preferences. With the species in the Nilgiri region feast on flowers, fruits and insects, their counterparts in the south of the Palakkad Gap remain steadfastly vegetarian by feasting on fruits and flowers. Within the regions of the Palakkad Gap, home to the Kerala Laughingthrush, there are two distinct zones. Here the sub-species of the Kerala Laughingthrush – the Palani Laughingthrush is found to the south – and the Banasura Laughingthrush is found in Coorg and Wayanad region, which lies to the north of the Gap.

Fish

Almost all the rivers in the southern part of India have their origins in the Western Ghats. A total number of 102 species of fishes reside in these rivers and hill streams of the Ghats, of which 11 species belonging to the Garra genus are endemic in various isolated areas of the southern Western Ghats. As majority of the rivers of the Western Ghats empty out into the sea, these fresh water fish have developed a peculiar characteristic to help adapt to the conditions. “The fishes of this genus have a disc protruding on the ventral side near its mouth. It is known as a sucker and is used by the species to attach their bodies physically to either the roots of the trees, small tennis sized pebbles or boulders and rocks near the river banks,” elaborates Dr M Arunachalam, professor at the Sri Paramakalyani Centre for Environmental Sciences, Tamil Nadu. This, he states, “allows the fish to avoid getting washed out into the sea while maintaining their velocity in the rapid river current.” The Garra gotyla stenorhynchus belonging to this genus is found, thanks to its limited distribution pattern, only in the tributaries of the Kaveri basin. Another species called the Tunga Garra (Garra bicornuta), found only in the Tunga River in Karnataka, has two distinct horn like structures on the dorsal side of its head, near its mouth, which are made of keratin and in some cases are often used as a defence mechanism by them,” says Arunachalam. The Kalakad Garra (Garra kalakadensis), found in the Pachayar River in Kalakad Mundanthurai Tiger Reserve region is characterised and identified by its physical appearance. “In order to survive in the cold waters of the Western Ghats, the Kalakad Garra, has undergone an evolutionary adaption, thereby ridding its body of scales and having a naked ventral side.”

Elephants

The elephant population is focused mainly in the Nilgiri, Anamalai Hills and the Periyar regions in southern Western Ghats. There are a number of elephant corridors in the Ghats including the Nilgiri-Mysore-Wyanad Elephant Reserves that are spread over Tamil Nadu, Karnataka and Kerala. Another critical corridor lies in the Tirunelli region of Kerala that links the elephant population of Wyanad and Nagarahole with the Brahmagiri hills. A third critical corridor is in the Kollegal region, near the settlement of Bailur in Karnataka. Recent studies have discovered a genetic differentiation in the elephants found in north and south of the Palakkad Gap based on analysis of their mitochondrial DNA. “The elephant population found in the Nilgiri region, which is spread over 15,000 sq km, north of the Gap, can be traced to a single matriarchal lineage,” says Prof Raman Sukumar, an ecologist from the Centre of Ecological Studies at the Indian Institute of Sciences, Tamil Nadu. On the other hand, research further showed the Nilgiri population of elephants to be genetically distinct from those found in the Anamalai Hills and Periyar regions, separated by the 40 km Palakkad Gap. “Here, three mitochondrial haplotypes (which in genetics is a combination of alleles (DNA sequences) at adjacent locations (loci) on the chromosome that are transmitted together) have been discovered among the elephants living in the south of the Gap. Though these differences among these haplotypes maybe small, as they all belong to the Beta elephant clade common in southern and east-central India,” he concludes. While the reason behind this genetic disparity is still elusive, it is indicative of the Gap acting as a biogeographic barrier in the past.