Archive for the ‘Human Species’ Category
… Photosynthetic unicellular organisms. Oxidation. Mutation. Natural selection and evolution. Respiration. Cell differentiation. Sexual reproduction…
(Excerpted from “The History of the Universe in 200 Words or Less” by Eric Schulman
© copyright 1996-1997. by Eric Schulman)
Located on the web at: http://members.bellatlantic.net/~vze3fs8i/hist/hist.html
Can Genealogy DNA Testing take us back to the beginning?
As of today scientists, historians and genealogists have fairly reached the conclusion that the following list of bi-peds are in the evolutionary chain of human like creatures that inhabited earth and that evolved in to modern day Homo Sapiens.
Here are some fairly acceptable date ranges for various Hominid species.
Homo Habilis – 2.2 to 1.6 million years BCE (Before Common Era 2010)
Homo Erectus – 2 to 0.4 million years BCE
Homo Sapiens – 400,000 to 200,000 BCE
Homo Sapiens Neandertalensis – 200,000 to 30,000 years BCE
Homo Sapiens Sapiens – 130,000 years BCE to present.
(Washington State University)
Apparently most of us, at least Americans, resemble some of our ancestors as depicted in this sculpture known as the Venus of Dolni Vŭstonice, one of the earliest known figurines depicting the human body. Dates back to about 29,000 to 25,000 BP. (Before Present 1950,) or say, about 27,000 BC. (courtesy wikipedia)
Humans are noted for their desire to understand and influence their environment, seeking to explain and manipulate natural phenomena through science, philosophy, mythology and religion. This natural curiosity has led to the development of advanced tools and skills, which are passed down culturally; humans are the only animal species known to build fires, cook their food, clothe themselves, and use numerous other technologies.
Seems I recall that we along with apes and monkeys have and use opposable thumbs that are able to articulate which is a pretty handy feature for climbing trees and other tasks. I know that I am a super being in the eyes of my three dogs. They trust me for their next meal. I make light appear magically when I enter a room, and best of all I can turn a door handle.
Ultimately researchers will not fully agree on exact times and dates but through the use of DNA testing we can get almost all the way back to the earliest known one of three, or one of seven, female ancestors.
That is quite an accomplishment for sure.
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The possibility of small amounts of Homo erectus DNA in modern man does exist. Just like there is trace amounts of Neanderthal DNA, it could be a part of our genetic makeup. This is disputed by some in the genetic field of study, but also has supporters.
The Homo erectus as a species was present on the earth for over 1.2 million years. Their presence has been mainly found in Asia. This period ended some 70,000 to 50,000 years ago with extinction during the Toba catastrophe. This was when the Toba, a volcano in Sumatra, Indonesia erupted. This is thought to be the largest eruption in the history of Earth. It is credited with a 6 to 10-year volcanic winter that dramatically changed the living conditions on earth in a very short time span.
This supervolcano eruption also had long term effects on the world’s climate. It is credited with a 1,000-year period in which the earth’s surface remained cooler than it had been previously. This is also the same time period in which the human evolutionary traces appeared to be bottle necked. It is estimated that only 1000 to 10,000 breeding pairs of Homo sapiens survived this period.
This bottle necking of the species is the leading reason for the theory that modern man can trace their genetic roots back to three females that survived this catastrophic event.
The intermixing of Homo erectus and Homo sapien could have only occurred in Asia before this event took place. There is some evidence that more people survived this event in Asia than previously known which allowed for some interbreeding between the species after this event, but the possibilities is highly reduced.
There is little to no evidence of male Homo erectus samples in modern man but because of it, genetic makeup female mtDNA from Homo erectus could still be present. There are studies that are being conducted on Homo erectus DNA with the purpose of exploring the past of modern man. With this increasing knowledge, a clearer picture is emerging but is not complete as of this date and time.
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In 1997, the Neanderthal DNA test became a reality when DNA from the remnants of a Neanderthal was successfully extracted from the right humerus of a known Neanderthal skeleton. These remains were found in a cave in the Neander Valley in Germany. The bones itself were recovered in 1856 and are the property of the Rheinisches Landesmuseum in Bonn.
Of the 3.5 gram sample that was taken, 379 different amino acid pair sequences were identified. What was found out was the Neanderthal DNA had 27 differences between itself and modern Homo sapiens.
With this information, it was determined that the Neanderthals and Homo sapiens had a common ancestor nearly 550,000 to 690,000 years ago. The two species then independently developed but still had limited contact with each other. There is evidence of trading between the two species as recent as 34,000 years ago in the remains at Arcy-sur-cure France.
The newest Neanderthal remnants are only 30,000 years old. The reason for their demise is still unclear, but remains found in a Croatian cave that was 38,000 years old showed signs of cannibalism.
It is thought that interbreeding of modern Homo sapiens and Neanderthals occurred between 45,000 and 80,000 years ago which is why there are remnants of their DNA in modern man. In 2010, it was reported that 1 to 4 percent of all non-African descendants have Neanderthal DNA present in their genome.
One of the commonalities of modern man and Neanderthals from the DNA is the ability to taste bitter objects, while 25% of modern humans cannot. This is thought to be an advantage since a bitter taste is associated with the toxicity level of many plants.
More and more is being discovered all the time. Since the first sample was extracted in 1997, more than 62,250 units have had a Neanderthal DNA test conducted on them and established their identity. In time, more commonalities will be released to the public.