Showing posts with label Reference and Education. Show all posts
Showing posts with label Reference and Education. Show all posts

Wednesday, November 28, 2012

What Evolution Is

The Theory of Evolution began with Charles Darwin and his book, Origin of Species. Interestingly, he did not conclude that evolution began billions of years ago in a chance combination of just the right chemicals. He simply observed that many species were similar enough that they appeared to come from a common ancestor. Despite its "evolution" into what it is today, it has become the default scientific explanation of the origin of life.

To understand evolution, one must understand the difference between the origin of life and the tiny changes that we do see happen and are clearly happening. The origin of life is thought to have taken place billions of years ago when the earth was rather young and was bathed in water and a plethora of simple molecules that included carbon, nitrogen, oxygen, iron, chlorine, etc. In other words, the ingredients of life. It is believed that with the aid of energy from the sun, these chemicals combined in various combinations and every once in a while, or maybe just once, the one in a million chance (so to speak) would cause a combination that could be classified as primitive life giving molecules. Eventually these combined to make more complex molecules until they formed into what would be considered a very simple cell of come sort.

Now of course it is thought that even basic molecules were very uncommon, and the more complex they became the lesser and lesser chance they had of forming, but that the one in a billion billion billion billion, etc. ended up as a cell. Of course this took place over millions of years, it is not supposed to have happened in a short time. However, for some random reason, a tiny fraction, or perhaps even just one of these few primitive cells, through pure chance, happened to have the ability to divide, which it began doing. Soon there were lots of these cells and as they filled the ocean, natural selection began to take effect and most of them died off, but every once in a while, one would have a mutation that allowed it to adapt a little better and therefore reproduce.

It is this natural selection that we see every day. We know for example that wolves were the original ancestors of dogs. This is an example of evolution, just evolution that humans forced. Every once in a while, a wolf was a little tamer than normal and then bred to produce offspring that were also tame. Over many generations, they became what we call dogs today. There are also clear similarities between animals in different places because their environments demanded slightly different survival properties.

These distinctions are important because no one is positing that species can't change over time, but many deny that life could have come from a pool of non-living molecules purely by chance. So when you say that you don't buy into evolution, you don't usually mean that minor attributes of species cannot change over time, you mean that you don't think life originated with a pool of slime. Not understanding the difference can make it seem that you do not know what is evolution.

Often Invasive Species Don't Appear to Be a Problem At First - Then All of a Sudden, Wham!   

What Evolution Is

The Theory of Evolution began with Charles Darwin and his book, Origin of Species. Interestingly, he did not conclude that evolution began billions of years ago in a chance combination of just the right chemicals. He simply observed that many species were similar enough that they appeared to come from a common ancestor. Despite its "evolution" into what it is today, it has become the default scientific explanation of the origin of life.

To understand evolution, one must understand the difference between the origin of life and the tiny changes that we do see happen and are clearly happening. The origin of life is thought to have taken place billions of years ago when the earth was rather young and was bathed in water and a plethora of simple molecules that included carbon, nitrogen, oxygen, iron, chlorine, etc. In other words, the ingredients of life. It is believed that with the aid of energy from the sun, these chemicals combined in various combinations and every once in a while, or maybe just once, the one in a million chance (so to speak) would cause a combination that could be classified as primitive life giving molecules. Eventually these combined to make more complex molecules until they formed into what would be considered a very simple cell of come sort.

Now of course it is thought that even basic molecules were very uncommon, and the more complex they became the lesser and lesser chance they had of forming, but that the one in a billion billion billion billion, etc. ended up as a cell. Of course this took place over millions of years, it is not supposed to have happened in a short time. However, for some random reason, a tiny fraction, or perhaps even just one of these few primitive cells, through pure chance, happened to have the ability to divide, which it began doing. Soon there were lots of these cells and as they filled the ocean, natural selection began to take effect and most of them died off, but every once in a while, one would have a mutation that allowed it to adapt a little better and therefore reproduce.

It is this natural selection that we see every day. We know for example that wolves were the original ancestors of dogs. This is an example of evolution, just evolution that humans forced. Every once in a while, a wolf was a little tamer than normal and then bred to produce offspring that were also tame. Over many generations, they became what we call dogs today. There are also clear similarities between animals in different places because their environments demanded slightly different survival properties.

These distinctions are important because no one is positing that species can't change over time, but many deny that life could have come from a pool of non-living molecules purely by chance. So when you say that you don't buy into evolution, you don't usually mean that minor attributes of species cannot change over time, you mean that you don't think life originated with a pool of slime. Not understanding the difference can make it seem that you do not know what is evolution.

Often Invasive Species Don't Appear to Be a Problem At First - Then All of a Sudden, Wham!   

Can Terrestrial Life Have Extraterrestrial Origin?

Crick (1973) advanced the idea that life was originally seeded on Earth from space - the idea of Panspermia. The British astronomer Fred Hoyle and Srilankan Chandra Wickramsinghe have further raised the possibility of Panspermia (1981).

The whole idea of Panspermia is the outcome of inability to satisfactorily explain origin of life on Earth despite accumulation of vast amount of data since Alexander Oparin (1924) first published his paper on this subject. He speculated that early Earth had reducing atmosphere. He considered it essential for Origin of life on Earth.

Even demonstration of origin of amino acids under physico-chemical influences by Miller - Urey (1953) has not resolved the question of spontaneous origin of life on Earth. In fact much work has been done after Miller - Urey to bridge the gap between inanimate and animate but still spontaneous transformation of inanimate into animate remains a matter of faith and belief. Till date, it is not possible to even conjecture spontaneous origin of a single polypeptide chain, what to talk about spontaneous origin of the simplest biological cell.

The gap between inanimate and animate remains as wide as ever.

Demonstration of amino acids, purine and pyrimidine bases in meteorites bombarded on earth, specifically Murchison meteorite; and presence of polycyclic aromatic hydrocarbons in space does not tell us anything about origin of life, whether on Earth or elsewhere. These findings only indicate feasibility of spontaneous origin of these chemicals under physico-chemical influences and nothing more.

All the work done so far demonstrates only one or more aspect of 'life like activity' but does not explain origin of life itself. Known properties of RNA are far from constituting life. Even recent analytical study by Bokov and Steinberg (2009) indicating feasibility of step-by-step evolution of ribosome at structural level beginning from a small core leaves much to be desired to constitute life.

Theory of extraterrestrial origin of terrestrial life, i.e. Theory of Panspermia may provide some relief from the question of explaining origin of life on Earth but it lands us into the question of explaining origin of life in extra-terrestrial space. So, we aren't in any better position with our original question.

Theory of extraterrestrial origin of life leads to further questions. If life was seeded from space, than how could it be found 5 Km below the surface of Earth in the form of extremophiles bacteria or 9000 meters below sea level on the ocean floor of Galapagos rift in the form of Poganophora. Barophillic Marine microbes have been found at more than 10 Km depth in Marianas Trench. Therefore, distribution of life on Earth is inconsistent with extraterrestrial origin of life.

Theory of Panspermia also raises the question of adaptation or survival of alien life under the conditions seen on Earth. All the available evidence indicates that alien life if any, must have originated under quite different environmental conditions than seen on Earth. So, how could alien life survive on Earth and evolve to the present state? Gradual adaptation over an immense period of time in line with Darwinism is more easily said than can be done.

Hence, Theory of Panspermia or Extraterrestrial Origin of life is nothing but scientific fiction created with the sole purpose, to divert attention from the question of origin of life.

Often Invasive Species Don't Appear to Be a Problem At First - Then All of a Sudden, Wham!   

What Evolution Is

The Theory of Evolution began with Charles Darwin and his book, Origin of Species. Interestingly, he did not conclude that evolution began billions of years ago in a chance combination of just the right chemicals. He simply observed that many species were similar enough that they appeared to come from a common ancestor. Despite its "evolution" into what it is today, it has become the default scientific explanation of the origin of life.

To understand evolution, one must understand the difference between the origin of life and the tiny changes that we do see happen and are clearly happening. The origin of life is thought to have taken place billions of years ago when the earth was rather young and was bathed in water and a plethora of simple molecules that included carbon, nitrogen, oxygen, iron, chlorine, etc. In other words, the ingredients of life. It is believed that with the aid of energy from the sun, these chemicals combined in various combinations and every once in a while, or maybe just once, the one in a million chance (so to speak) would cause a combination that could be classified as primitive life giving molecules. Eventually these combined to make more complex molecules until they formed into what would be considered a very simple cell of come sort.

Now of course it is thought that even basic molecules were very uncommon, and the more complex they became the lesser and lesser chance they had of forming, but that the one in a billion billion billion billion, etc. ended up as a cell. Of course this took place over millions of years, it is not supposed to have happened in a short time. However, for some random reason, a tiny fraction, or perhaps even just one of these few primitive cells, through pure chance, happened to have the ability to divide, which it began doing. Soon there were lots of these cells and as they filled the ocean, natural selection began to take effect and most of them died off, but every once in a while, one would have a mutation that allowed it to adapt a little better and therefore reproduce.

It is this natural selection that we see every day. We know for example that wolves were the original ancestors of dogs. This is an example of evolution, just evolution that humans forced. Every once in a while, a wolf was a little tamer than normal and then bred to produce offspring that were also tame. Over many generations, they became what we call dogs today. There are also clear similarities between animals in different places because their environments demanded slightly different survival properties.

These distinctions are important because no one is positing that species can't change over time, but many deny that life could have come from a pool of non-living molecules purely by chance. So when you say that you don't buy into evolution, you don't usually mean that minor attributes of species cannot change over time, you mean that you don't think life originated with a pool of slime. Not understanding the difference can make it seem that you do not know what is evolution.

Often Invasive Species Don't Appear to Be a Problem At First - Then All of a Sudden, Wham!   

Twitter Facebook Flickr RSS



Français Deutsch Italiano Português
Español 日本語 한국의 中国简体。