Nature on the Earth has mind boggling diversity. Evolution has enabled species to diversify themselves and morph into altogether different species which are better equipped to adapt themselves to changing scenarios of weather and other variables like food availability and predator defence. Living beings are morphed into some of the strange shapes and sizes. Centipedes are the prime example.
Everyone must have seen Centipedes. Those crawling fear inspiring creatures. Although there are so many species of them, but all are called centipedes. How the name came about? Centipede means the one with 100 feet. But this is not true. The number of legs depend upon the segments present in the body of the centipede.
Centipedes have many species which have different sizes and number of legs. A full adult centipede can have 15 to 177 pairs of legs. This means the number of feet varies from 30 to 354. Typically a centipede has two legs per segment.
For example, Lithobiomorpha and Scutigeromorpha species have 15 pairs of legs. Scutigera have long, multi-articulate, hairy legs. It helps them to establish a solid grip on the ground and move very quickly but they are incapable of pushing themselves through soil or into detritus. The colorful Scolopendromorphs have from 21 to 23 pairs of legs.
The two legs in the first segment behind the head has been morphed into venomous fangs for hunting the prey. Legs of Centipedes become progressively larger as one moves from head to tail. This is evolutionary modified to provide better balance while moving. The tail legs are modified into sensory antennae to help the centipede move back when it encounters a dead end.
Murmuration of some birds is a strange but fascinating phenomenon. It has been observed with common starlings in Europe and India. In this phenomenon, groups consisting of thousands of birds fly together and are joined by more and more groups from the neighborhood. They fly together going up and down, changing direction suddenly making breathtaking patterns. But even being so close, they hardly collide with one another.
I was lucky to observe this phenomenon by chance but not with starlings which are not in plenty in our area but with House Sparrows.
So It was a double bonus and surprise. I at least have the notion that house Sparrows live in houses in small groups and also the most common belief that the population of house sparrows has declined to dangerously low levels. But I was proved wrong when I spotted them in the fields.
It was dusk time when it all started. I was roaming with my camera in the field located nearby to my home. There are two or three excavated areas in the fields which have become water bodies and Reed grass grows in them in adundance. It was early April and wheat crops have been reaped.
Suddenly, groups began arriving and joining over an area of say about 1 kilometer radius. The group will perform those maneuvers and suddenly once in while land on the electric transmission wires passing that place or plunge into the reeds. The numbers must be thousands. Then suddenly they will again take off and perform those maneuvers in the sky. This went on for till the darkness descended.
This was observed by me on three different evenings. Lastly, since two day in a row, the Sparrows have left the place suddenly. Baffling me. Why they have left and where they are headed. One apparent change is of course the reaping of the wheat harvest in those fields. But still the explanation is uncertain.
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.
In the preface to his book named “Mutual Aid: A factor of evolution”, Russian Anarchist, Peter Kropotkin writes ” Two aspects of animal life impressed me most during the journeys which I made in my youth in Eastern Siberia and Northern Manchuria. One of them was the extreme severity of the struggle for existence which most species of animals have to carry on against an inclement Nature; the enormous destruction of life which periodically results from natural agencies; and the consequent paucity of life over the vast territory which fell under my observation.
And the other was, that even in those few spots where animal life teemed in abundance, I failed to find–although I was eagerly looking for it–that bitter struggle for the means of existence, among animals belonging to the same species, which was considered by most Darwinist (though not always by Darwin himself) as the dominant characteristic of struggle for life, and the main factor of evolution.”
Thus according to him, this means that mutual cooperation and mutual aid are as important for evolution as are competition and mutual strife. This also means that human beings are basically good at heart.
Many great scientists have commented on his ideas. Stephen Jay Gould says that “a common conceptual error in failing to recognize that [Darwinian] natural selection is an argument about advantages to individual organisms”. and secondly that “there are no shortcuts to moral insight” and that the answers to such questions must be found within us, not in nature. But overall, the ideas of Kropotkin are very respectable and form the basis of principle that individuals in society in general benefit from mutual cooperation.
Alexeyevich Kropotkin was (9 December 1842 to 8 February 1921) was one of Russia’s foremost anarchist and one of the first advocates of anarchist communism: most of his life he advocated for a communist society free from central government. Because of his title of prince and his prominence as an anarchist in the late 19th and early 20th centuries, he was known by some as “the Anarchist Prince”. Some contemporaries saw him as leading a near perfect life, including Oscar Wilde, who described him as “a man with a soul of that beautiful white Christ which seems coming out of Russia”. He wrote many books, pamphlets and articles, the most prominent being The Conquest of Bread and Fields, Factories and Workshops and his principal scientific offering, Mutual Aid: A Factor of Evolution from which this matter is taken.
In short, Kropotkin, was the father of altruism. Modern theories run against this thought. Nowadays, it is held, that whatever an individual does is basically for his own benefits and happiness. Even in situations where it seems that an individual benefits from the action he is performing, in reality he is being selfish for his own happiness. Suppose, a person, sees an child leaping in the fire and he even does no the child, he will go for saving the child. This will save him from the guilty feeling and remorse he will suffer in the aftermath and his happiness will not be under jeopardy.
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.
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.
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.
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 teens 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.
The more I watch the nature closely and more I go through the literature, it is becoming clear how shallow is our knowledge of the world around us which the God has created.
Sometimes I become more and more confused and become awestruck when some mystery of nature becomes clear to me.
As we know that living things are related to one another at some stage or other during evolution though they must have diversified at some period of time but at least some basic properties resemble.
By the end of January and February, one can notice that Pipal trees which is very sacred tree of India, copiously shed their leaves. All day the leaves fall to the ground following zigzag trajectories. The wind forces them to float and it seems that they are reluctant to fall to the ground beneath the tree.
Whole ground beneath the tree becomes strewn with leaves. Within few days, the trees look like skeletons, completely shorn of leaves. All the other trees around them have already acquired new green leaves.
But it is matter of days. The new translucent leaves burst out of the branches and the whole tree is decorated with reddish brown leaves which seem to be very beautiful. One can notice the change which the tree undergoes and it is completely covered with lush green leaves. Then many birds are seen visiting them. They are there for eating the very small rounded green fruits. If you break this fruit with slight pressure of fingers you can see that inside is just like figs.
At the same time, there are other trees, the trunks of which are covered with similar type of fruits as that of Pipal. But these fruits are very numerous, bigger and become brown red on ripening. The ground is totally covered with these fruits and there is smell of food decomposition and formation of alcohol due to fermentation. Lots of ants roam on the tree and bore into the delicate fruits to eat the fruit inside. The fruit bear uncanny resemblance to Pipal fruits.
Otherwise, the look of both these trees is completely dissimilar. Leaves are different. While Banyan tree has cordate type of leaves, the Indian Fig has lanceolate types of leaves.
But in my mind, the picture began to became clearer that may be they were related. Internet queries revealed the truth. Both are ficus genera and are commonly called figs. The botanical name of Pipal or Banyan is Ficus religiosa and other one is Indian fig.
Charles Darwin’s work on the evolution theory is akin to the Laws of Motion by Newton. They stood like indestructible rocks for several decades. Yet as the new evidence gathers, chinks or limitations in these laws have been becoming visible. Einstein came and with his theory of relativity, made the laws of motion into approximation of the true laws at lower speeds. These laws breakdown and cannot explain phenomena at the extremities at both ends, at the sub atomic level as well as the parsec levels. Not only that, it is now doubted that Einstein’s theories which are based on the premise that speed of light is the ultimate barrier are correct or can explain all the observation.
Similarly, the Darwin’s theory has been found to have chinks. Its main postulate is that in nature evolution is taking place gradually. Dr. Stephen Gould amassed the available data and announced that things did not happen in gradual manner but in bursts with periods of lull or nonconformities in between. There were periods of intense activity in which many new species appeared and others got decimated. Now with the passage of every day, this theory seems to gaining strength.
Most obvious is the case of weather. Areas which were deserts are experiencing lots of rainfall, the areas which were previously most rainy are becoming devoid of the rain. Rains fall in torrents of such intensity that it seems that the land will submerge into the sea and it will like the olden times when all of Indian subcontinent was under the sea.
Then there will be periods of complete dry spells. So we have the perfect recipe for the disaster. First face the floods, then diseases in the aftermath, destruction of crops and increase in hunger. Oh God, was it the fate of the Earth when I was born?
When we observe the trees and plants around us, we find that even the plants of the same species bear different sizes and shapes. In fact no two trees are alike even if they are growing near one another. This is the result of the intense competition and many traits that trees have to face and acquire.
Every tree tries to reproduce to propagate its lineage. For this it produces seeds. But this is not the end of the story. The seeds have to be broadcast away from the tree preferably to a place where the parent tree does not have its influence over the resources required for growth. To scatter the seeds the tree shall in ideal case try to grow very tall and branches at the top.
Now take its second trait. Every tree has to harvest the sun energy. For optimal absorption of the energy the tree shall desire to have the design in which branches shall be horizontal and non-overlapping. This way every leaf will act as a energy cell.
Third trait is mechanical stability. For this the tree shall want minimum horizontal branches because the branches shall try to destabilize it.
Now as the saying goes no one gets the complete world. The foremost truth about the life is compromise. So when all the traits compete simultaneously there is compromise. The mixing ratios of the traits is the result of the helplessness of the tree. This behavior has been called “Frustration Principle” by biologist Karl Niklas. Niklas used computer models in which he kept the two traits constant and varied the third one. The results were as expected but when he mixed the traits in different ratios the final shape of the tree was like we see in reality around us.
This can be compared to smart cellphones which have a camera also. Although cellphone camera does good work but it cannot replace the stand alone camera. Similarly we have gadgets which can do many jobs but they are good for picnics where it is not the refinement but collection of many tools which come as handy but are not as perfect in quality as the individual tool shall be. But then who wants to take a lots of tools for picnic?