We are living in the Meghalayan Age

Scientists have marked the time since the Earth began its life. They have divided it into different Epochs, Periods, Eras and Eons progressively in increasing time groups.

 

We are living in the following division of time.

Eon: Phanerozoic

Era: Cenozoic

Period: Quaternary

Epoch: Holocene

Holocene epoch began roughly 11700 years back and continues till present. United States Geological Survey (USGS) has divided this time into three ages namely

Greenlandian: 11700 to 8326 years ago

Northgrippian: 8326 to 4250 years ago

MEGHALAYAN: 4250 to present date

MEGHALAYAN age marks the time when a mega drought devastated civilizations across the world, including those in Egypt, Greece, Syria, Palestine, Mesopotamia, The indus Valley and the Yangtze valley. Drought lasted some 209 years and supposed to be prompted by shifts in ocean and atmospheric circulation.

Geologists chose the name “Meghalayan” as a nod to a rock sample they analyzed from Meghalaya, a northeastern state in India, whose name means “the abode of clouds” in Sanskrit. By analyzing a stalagmite growing on the ground of Mawmluh Cave, geologists found that each of the stalagmite layers had different levels of oxygen isotopes, or versions of oxygen with different numbers of neutrons. This change marked the weakening of monsoon conditions from that time.

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50 Years of IR8 :: The rice variety which saved the world

Rice is the staple food of millions in South East Asia. People in South India and North East grow rice as the main crop. It is eaten with fish. It is the rice, that ushered green revolution in India and brought India back from the jaws of starvation. Punjab became the leader in growing the rice, a crop which was alien to North india as most people liked wheat. It is another matter that Punjab has to pay a untold price for feeding the Indian population.

Story of IR8 Rice

A few days back, it was 50 years ago, the rice variety nicknamed IR8 was launched and it saved millions in Asia and particularly in India from starvation and acted as a launchpad for Green Revolution in India.

It was almost a famine like situation in this area. The available production of edibles was insufficient to cope with the requirement. Traditional varieties of rice took 160 to 180 days for the crop cycle and yields were low.

The rice variety was developed by International Rice Research Institute (IRRI) which is based in Manila and works under FAO. The strain matures in 130 days and has higher yields for the same nitrogen consumption.

In the year 1962, the Institute made a cross variety using Peta, a Indonesian tall, pest resistant and vigorous variety with a dwarf Chinese variety called dee-geo-woo-gen (DGWG) in the laboratory.

During field tests in Taiwan, Malaysia, Hong Kong and Taiwan using the variety named IR8-288-3 showed great promise and yields it gave were almost 9 times the existing from 1 ton per hectare to 9 ton per hectare.

In Andhra Pradesh, a farmer called Nekkanti Subba Rao, experimented and sowed this rice in 2000 acres in Atchanta in West godavari. He earned the nickname of “Mr.IR8”.

The variety was commercially introduced in 1967 in the Vietnam during the American war.

The variety became popular worldwide and earned local nicknames worldwide. For example in Burma it is called Magyaw, Padi Ria in Malaysia ,Peta Baru 8 in Indonesia, Milagaru Philipino in Mexico . It was grown in Pakistan, India, Taiwan, China, and even in US.

In an interesting tale, a farmer K.N.Ganesan of Tamil Nadu named one of his sons “Irretu” meaning IR8 in Tamil.

Similarly in Vietnam the rice came to known as Honda rice as its bumper harvest enabled one farmer to purchase an Honda motorcycle.

 

 

Of all the predators Man is super predator

Darwin, the father of evolution, had postulated that the species evolve constantly to adjust to the changing environment and climatic changes but this change is gradual in nature and takes place over thousands of years. But man is proving him wrong. Being an expert killer backed by technical advanced equipment, man is bringing rapid changes which are perceptible within much shorter time.Man is super predator and its peculiar hunting preferences are forcing many species particularly of fish and large sized land animals to evolve at a rapid pace than the nature would have done. There are stories of attacks by sharks on people venturing into sea and of being killed by lions or other carnivorous animals but they fade away when compared to the man. Scientists at the Victoria university at British Columbia in Canada who are studying the changes and the harm being brought upon the fauna by the man has termed the man as “Super Predator

In general the man hunts the largest of the animals. For examples adults of lions and tigers to flaunt them as the trophies of their valour and skill as opposed to the hunting animals who generally go far the weakest and younger prey. Thus the man depletes the mature “reproduction capital” instead of the “reproductive interest” of the hunted species. For example, fish is caught in the nets and nets are so constructed as to retain the larger fish and filter out the smaller ones.

This is causing the the fish to mate early and produce the smaller broods. The size is diminishing. This is because the fish is also evolving techniques to survive and producing fish of smaller varieties which can pass through the larger net openings.

Man has hunted the sea creatures 14 times more than the sea predators and 9 times more than the land animals. Man is going for the bigger animals like sharks, tuna fish and marlin. This is changing the ecosystem at a much faster pace than nature.

  

Over Killing of the land predators has resulted in the increase of herbivore population. This increase is putting pressure on many resources and robbing the food from insects and birds which we cherish. And also resulting in producing the disease prone herbivorous animals.

Sleep deprived school teenagers

When Bejamin Franklin coined this advice “Early to bed, early to rise”, perhaps  he did not have teens in his mind. Also back then in his days, the pressure of schooling was not much. Even in our times, life was non competitive and relaxed. This is not the case today. Kids began going to school very early on. 

It has been found that schools which start early morning, teens are not fresh. They find themselves tired and sleepy. Now the science has begun to unravel the chemistry behind the sleep. 

Our bodies follow a rhythmic cycle of 24 hours duration. During this cycle, our bodies undergo different changes. For example blood pressure is more in the day than during night. These activities are controlled by certain clocks called biological clocks which are produced in the brain. These rhythmic cycles are called circadian. 

One such chemical called melatonin is responsible for control of sleep. It is synthesised from an amino acid called tryptophan by action of enzymes. There is a intermediate product also which is called serotonin. Melatonin triggers the sleep. The reactions sequence is given below.



How the brain gets signals from the areas controlling eyes light and directs the production and breakdown of enzymes during night and day.



The production of enzymes especially SNAT which converts the serotonin to melatonin depends upon the time of the 24 hours cycle. As the sun goes down, it’s production begins to increase and so is the production of sleep inducing melatonin. During night time, it is bound to a phosphate ion which results in its high stability. As the morning comes, the enzyme begins to degrade and our brain signals wakefullness. 

It so happens that the production of SNAT and melatonin in teens happens 2 to 3 hours later than children and adults, so teen find it difficult to go to sleep early. Since teens on average require 9 hours of sleep, going to bed late means deprivation of sleep. This results in laziness, sad mood, and poor performance in class. 

In USA , many schools have changed the starting time to late that is around half past eight and found the rise in the performance of the teens and cheerful attitude. 

Animals take drugs when in grief

Man’s penchant for getting drunk is much older than keeping himself clean. I mean the use of alcohol and other substances obtained from plants which give high is much older than the invention of soap for cleaning the body. But it is not only the humans who feel the need to get a high but many animals also are similar. Johann Hari, who is the author of book “Chasing the Scream: The First and Last Days of the War on Drugs” has spent 25 years observing the behaviour of animals when in they are alarmed or in grief. He began his research after going through the findings on this subject from Ronald Siegel. For example, Siegel had planted “Silver Morning Glory” a plant containing powerful hallucinating chemicals in the pen of Hawaiian mongoose. The animals tasted it leaves felt disoriented and avoided the plant altogether. But there happened a tropical storm which destroyed the den, filled it with mud and female dead. The male returned to the plant and ate its leaves to get blasted out of mind. After that Hari began his research and found more evidence. For example, in Vietnam, he found that prior to bombings in the Vietnam war with America, the buffaloes never chewed on opium plants. But when the bombings began, the water buffaloes ate the opium plants. They became dull and dizzy to escape their thoughts like mongoose. Similarly, bees bees fell to ground in a temporary stupor after sampling the numbing nectar of certain orchids. Birds gorge themselves on inebriating berries, then fly with reckless abandon. His more observations are given below : “Cats eagerly sniff aromatic “pleasure” plants, then play with imaginary objects. Cows that browse special range weeds will twitch, shake, and stumble back to the plants for more. Elephants purposely get drunk off fermented fruits. Snacks of “magic mushrooms” cause monkeys to sit with their heads in their hands in a posture reminiscent of Rodin’s Thinker. The pursuit of intoxication by animals seems as purposeless as it is passionate”

Human Eye

Human eye is a very complex structure. It can distinguish about 10 million colors. There are rod and cone cells in the retina which allow conscious light perception and vision including color differentiation and the perception of depth.

According to the evolution theory of Darwin, the living things evolved from simple to the  the complex through gradations. So evolution of the eye poses a challenge to the Darwin’s theory because eye consists of many parts intricately connected to each other. The critics argue how could something so complex, they argue, have developed through random mutations and natural selection, even over millions of years?

If evolution occurs through gradations, the critics say, how could it have created the separate parts of the eye — the lens, the retina, the pupil, and so forth — since none of these structures by themselves would make vision possible?

Darwin acknowledged from the start that the eye would be a difficult case for his new theory to explain. Difficult, but not impossible. Scientists have come up with scenarios through which the first eye-like structure, a light-sensitive pigmented spot on the skin, could have gone through changes and complexities to form the human eye, with its many parts and astounding abilities.

Through natural selection, different types of eyes have emerged in evolutionary history — and the human eye isn’t even the best one, from some standpoints. Because blood vessels run across the surface of the retina instead of beneath it, it’s easy for the vessels to proliferate or leak and impair vision. So, the evolution theorists say, the anti-evolution argument that life was created by an “intelligent designer” doesn’t hold water: If God or some other omnipotent force was responsible for the human eye, it was something of a botched design.

Biologists use the range of less complex light sensitive structures that exist in living species today to hypothesize the various evolutionary stages eyes may have gone through.

Here’s how some scientists think some eyes may have evolved: The simple light-sensitive spot on the skin of some ancestral creature gave it some tiny survival advantage, perhaps allowing it to evade a predator. Random changes then created a depression in the light-sensitive patch, a deepening pit that made “vision” a little sharper. At the same time, the pit’s opening gradually narrowed, so light entered through a small aperture, like a pinhole camera.

Every change had to confer a survival advantage, no matter how slight. Eventually, the light-sensitive spot evolved into a retina, the layer of cells and pigment at the back of the human eye. Over time a lens formed at the front of the eye. It could have arisen as a double-layered transparent tissue containing increasing amounts of liquid that gave it the convex curvature of the human eye.

In fact, eyes corresponding to every stage in this sequence have been found in existing living species. The existence of this range of less complex light-sensitive structures supports scientists’ hypotheses about how complex eyes like ours could evolve. The first animals with anything resembling an eye lived about 550 million years ago. And, according to one scientist’s calculations, only 364,000 years would have been needed for a camera-like eye to evolve from a light-sensitive patch.