Darwinism

Human Eye

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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.

Mutual Aid or Cut throat Competition?

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Darwin, father of the theory of evolution, taught us the behavior of species. The main tenet of his theory was that when the resources for which the members of an animal are competing are not sufficient, there is a fierce struggle amongst the members to outdo one another and in the end it is the strongest and fittest which emerges the winner. This theory has many opponents not only in religious quarters but within science itself. And the issue is not satisfactorily settled.

English: Charles Darwin (1809-1882) in his lat...

For almost 100 years, no single person did more to promote the study of the evolution of cooperation than Peter Kropotkin. His thesis is also based on thousands of observations he made while visiting through Siberian jungles and villages. There resources are threadbare. But he did not find the brutal dog-eat-dog world of Darwinian competition. He searched high and low—but nothing. “I failed to find, although I was eagerly looking for it,” Kropotkin wrote, “that bitter struggle for the means of existence, among animals belonging to the same species, which was considered by most Darwinists (though not always by Darwin himself) as the dominant characteristic of the struggle for life, and the main factor of evolution.”

English: Peter Kropotkin

Instead he saw mutual aid—everywhere. “In all these scenes of animal life which passed before my eyes,” Kropotkin wrote, “I saw Mutual Aid and Mutual Support carried on to an extent which made me suspect in it a feature of the greatest importance for the maintenance of life, the preservation of each species and its further evolution.” And it wasn’t just in animals. The peasants in the villages he visited were constantly helping one another in their fight against the brutal environment of Siberia. What’s more, he noted a correlation between the extent of mutual aid displayed in a peasant village and the distance of that village from the hand of government. It was just as the anarchists had suggested. “I lost in Siberia,” he wrote, “whatever faith in state discipline I had cherished before. I was prepared to become an anarchist.”

And now another piece of research has thrown its weight with Kropotkin. Complex social behavior was considered to be unique in animals, especially humans.  Now with recent findings, we may need to extend this ability to plants.  The old wives tale, “if you talk to your plants, they will grow better” may actually have a string of truth to it.  Except they don’t have ears to hear, they have chemical sensors in their roots, like “tongues in the earth.”

Recent studies have shown that plants seem to respond to other neighboring plants, and will alter their growth patterns accordingly.  At McMaster University, Ontario Canada, Susan Dudley and Amanda File have demonstrated that plants grown near their siblings are less competitive than when they are grown near unrelated “strangers” of the same plant.  The response of plants to competition in their environment has been well documented.  They are known to sprout deeper roots for water and nutrients.  However, recognition of their own genetic kin has never been seen before.

In their experiment, Dudley and File grew batches of Cakile edentula (the Great Lakes Sea Rocket) together in pots of four.  Some were paired with members of the same maternal family and others were paired with unrelated families.  Considering that the plants were of the same species, the growth of their root masses were expected to be the same.  Surprisingly, a greater mass of roots were grown when plant “strangers” were grown next to each other, while less root mass was associated with tandem plants of the same maternal line, thus indicating a sharing of resources as opposed to competing for them.  The mechanism behind plant kin recognition is still a mystery.

Dr.Stephan Gould Seemed to be right

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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.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 it was born?