Evidence Of Evolution: The Combination of Variation, Natural Selection, and Heredity Unquestionably Results in Evolution

 
Evidence of Evolution:
 
Evolution-Photo-by-Tkgd2007-450x281
 
This can be simplified with the following examples:
 
Europeans descended from dark-skinned (black) origins, yet today, we find that their skin is white. Actually, they are grades of white. For example, southern Europeans are less white than northern Europeans because favored races were selected by the environment. As for the reason that nature selected white skin, it might simply be due to Vitamin D, which requires sunlight to penetrate the skin for it to be synthesized, as dark skin prevents or reduces the penetration of sunlight.
 
In Europe, where there is less sunlight, people with dark skin are at higher risk of developing Vitamin D deficiency, which poses a threat to life and reproduction, so the fittest survive. Since variation in skin to life and reproduction, so the fittest survive. Since variation in skin color (or pigment) will inevitably occur, light skin is selected because in an environment with little sunlight, a person with light skin is fit to survive. So in this way, an inevitable sifting process occurs, and this continues one generation after another until the skin attains a color that is suitable for the environment. 
 

The same applies to nose size, height, and other traits.

 
Exposure to a new environment inevitably causes an adaptation to it. In the 50,000-100,000 years since the African diaspora, there has been an opportunity for substantial adaptation, both cultural and biological. We can see traces of the latter in skin color and in size and shape of the nose, eyes, head, and body. One can say that each ethnic group has been genetically engineered under the influence of the environments where it settled. Black skin color protects those who live near the equator from burning under the sun’s ultraviolet radiation which can also lead to deadly skin cancers.
 
The dairy-poor diet of European farmers, based almost entirely on cereals that lack ready-made vitamin D, might have left them vulnerable to rickets (our milk still has to be enriched with this vitamin). But they were able to survive at the higher latitudes to which they migrated from the Middle East  because the essential vitamin can be produced with the aid of sunlight, from precursor molecules found in cereals. For this Europeans have developed the whiteness of their skin, which the sun’s ultraviolet radiation can penetrate to transform these precursors into vitamin D. It is not without reason that Europeans have, on average, whiter skin the further north they are born.
 
The size and shape of the body are adapted to temperature and humidity. In hot and humid climates, like tropical forests, it is advantageous to be short since there is greater surface area for the evaporation of sweat compared to the body’s volume. A smaller body also uses less energy and produces less heat. Frizzy hair allows sweat to remain on the scalp longer and results in greater cooling. With these adaptations, the risk of overheating in tropical climates is diminished.
 
Populations living in tropical forests generally are short, Pygmies being the extreme example (Cavalli-Sforza 1000, 10-11).[1]
 
Example: The change in the color of moths from white to black as a result of the industrial revolution. Moths benefited from their white color because the white bark of trees concealed them and they weren’t seen by birds. With the industrial revolution in Europe, tree bark blackened in some of the industrial areas as a result of the pollution caused by coal. The white moths were then exposed to birds, whereas the moths with a darker color mutation were able to remain hidden and survive. So the color of the moths changed within a short period of time, rather than requiring millions of years, because they have a short life cycle. Therefore, in the case of moths, a relatively short time period is sufficient for hundreds or thousands of generations to pass and for biological evolution to occur.
 
Example: The variable neck length of the ancestors of giraffes, with some having a relatively longer neck than others. If we assume that giraffes lived where food was at a height more suitable for those with long necks than short necks, then natural selection would occur, favoring the giraffes better suited for life in that environment.
 
Therefore, short-necked giraffes would either starve to death, or would be incapable of reproducing and mating due to insufficient food, or they wouldn’t be able to feed their young. In this way, the number of short-necked giralfes would decrease in this environment, and they might become extinct, whereas long-necked giraffes would survive and reproduce satisfactorily. So giraffes with the long-neck trait would increase in number and pass these genetic traits to their offspring, and the short-necked trait would be cleansed from the giraffe genetic plan, generation after generation.
 
These matters are practically self-evident, and proving their validity today using genetics is the same as proving that the earth spins around the sun using images. Nonetheless, a great number of people deny it just because they think it contradicts religious scriptures.
 
Example: Predatory animals such as wolves vary in all aspects, just like other organisms. If wolves exist in an environment where the prey is quick, then slow, short-legged wolves will starve to death, so they won’t pass their traits on to the next generation. With the passage of time, through natural selection, fast, long-legged wolves will develop in that environment. In a snowy environment, only white wolves will survive because the dark ones will be easily seen by the prey and won’t be able to hunt, so they will starve to death. In this way, the color of the wolf’s fur is gradually refined to white, and the same thing can happen to prey, such as when the fur of rabbits becomes white in order to aid in camouflage.
 
As for polar bears, their white color aids them greatly in camouflage while hunting their prey, so the prey don’t notice them until it is too late. Were it not for the white color trait, they might not have been able to obtain food. The white color is not acquired suddenly, but rather through the process of evolution, just as with the evolution of moths during the industrial revolution. Both occur when genetic mutations provide the option suitable for the survival, reproduction, and establishment of one trait at the expense of another. However, the time that it took for the polar bear to evolve from the brown bear was approximately 150,000 years according to Dr. Ian Stirling. This time period is far longer than that required by the moths of the industrial revolution, the reason being the difference between long and short animal life cycles, as I have clarified previously.[2]
 
Example: Nowadays, we all say that despite signficant advancements in construction, technology, and medicine, our health problems, diseases, and their complications have increased.
 
All of us—perhaps even some doctors—wonder, what is the reason for this?! Yet, one of the reasons is clear: it is simply that we have, with our advancements, eliminated one side of the evolution equation of our (physical) species: natural selection.
 
To clarify further, let’s examine any hereditary disease: diabetes, for example. The healthcare industry (doctors, laboratories, specialists, pharmacists, and medications, etc.) prolongs the life of diabetics so that they reach adolescence, have children, and pass their genes to their offspring. This causes an increase in the number of those among us who have these genes.
 
Therefore, with our advancements we have eliminated natural selection. Had we not added health care to the equation, natural selection would have occurred, and many diabetics would have died before reaching adolescence and being able to have children, so the number of people who have these genes would have gradually decreased.
 
In addition, due to our residing in somewhat protected houses, many people have become incapable of withstanding the difficulties associated with living in a natural environment, such as the ability to withstand germs or insect bites.
 
Moreover, there is a study regarding the biological elimination that befell the natives of the New World as a result of the germs carried by pets that were brought to this region by new settlers. While Europeans had adapted to living with these germs and developed a resistance to them, the natives of the New World hadn’t, so these germs gave rise to the restructuring of these populations based on the system of evolution.
 

 
[1] Professor Luigi Luca Cavalli-Sforza, born in 1922 in Genoa, is an Italian population geneticist who also worked in the field of anthropology. He received his MD in 1944 and collaborated with evolutionary biologist Ronald Fisher at Cambridge University. He has been a professor at Stanford University in California since 1970 (now emeritus), and is a member of the Lincean Academy. He won the Balzan Prize for the Science of Human Origins in 1999. He is also an emeritus member of the Italian Society for Evolutionary Biology.
 
[2] Doctor lan Stirling is considered one of the world’s leading authorities on polar bears. He has written and spoken extensively about the danger posed to polar bears
 
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