Where Did We Come From?
Where did we come from?
While that may sound like a strange question to ask, one which has an obvious answer, it is increasingly becoming a loaded question as geneticists and scientists uncover more truths about human DNA through the human genome project. One startling find they are making is that homo sapiens sapiens (the scientific name for modern day humans) have genes from other species of humans in its DNA. what’s even more interesting is that different ethnicities have small pieces of transposons of DNA from different species of humans.
The Denisovans, scientific name Homo Denisovans, lived in many parts of Asia some 30,000 years ago. They interbred with many of the ancestors of modern Asians and many ethnicities of Asians still harbor some of their transposons. For example, modern day Polynesians have 3% of Denisovan genes in their DNA. modern day Melanesians have 4-6% of key Denisovan genes in their DNA.
The other humans
Recent archaeological excavations and more intense analysis of the human genome have revealed that as many as ten species of humans may have coexisted with our direct ancestors as recently as 30,000 years ago! In fact, dozens more species of humans were thought to have roamed the African savannah about two million years ago when the human species first appeared on Earth. Our direct ancestor, Homo Sapiens Sapiens is thought to have first appeared on Earth some two hundred thousand years ago. These species of humans were very diverse, with some being small hobbit like creatures, and some resembling primates more than humans.
Where they lived
These species of humans lived in a variety of places. Some like Neanderthal man and Denisovan man migrated out of Africa many hundreds of thousands of years ago. Neanderthal Man, whose fossils were first found in the Neander valley in Germany in the early 20th century, lived in Europe and interbred with our direct ancestors who lived there. Denisovan man, on the other hand, lived in Asia, and again interbred with the local species of Cro Magnon Man (another technical name for modern day humans) who lived there. Many other species of humans lived in other far flung places on Earth and interbred with the Cro Magnon Men who lived in these areas. Recent archeological evidence is uncovering this, and it is also uncovering another startling and interesting fact: Not all humans initially evolved in Africa as was initially thought!
More about the other humans…
As mentioned earlier, because the different species of humans who once inhabited Earth along with Cro Magnon Man had many different transposons, they looked much different from each other, for the most part. However, some species of humans looked surprisingly similar to each other! Because all species of humans have a remarkable similarity to species of animals in the primate kingdom, and share most genes with them (except for a few key transposons) scientists, archaeologists, and geneticists believe that all species of humans evolved from different species of primates many millions of years ago. Our direct species, Cro Magnon Man, is believed to have evolved from the same common ancestor as the chimpanzee in an evolutionary process known as divergent evolution between four hundred fifty thousand and two hundred thousand years ago! These different species of humans are described in more detail below:
Archaeological analysis of their fossils and other remains suggests that this species of humans lived between seven hundred thousand and two hundred thousand years ago. They first evolved from a primate species in Africa. They resembled pygmies because of their short stature. The men were 175 cm tall and weighed 136 pounds, while the women were 157 cm tall and weighed 122 pounds. Archaeological analysis of their skulls revealed that they had a large cranial capacity. They had faces which were much flatter than those of modern day humans, and they were the first human species who had the ability to adapt to colder weather and climates. This gave them a huge advantage for mobility to cooler parts of the world as Earth’s climate began to change! The species of humans who lived on Earth before them largely ate plants, but Homo Heidelbergensis was different because they were the first humans with the intellectual capacity to hunt large game animals. They also had the jaws and teeth necessary to chew animal flesh, and they had the digestive system necessary to digest this flesh. This gave them a huge advantage because the animal proteins and fats which they ate allowed them to become more muscular and have a much larger skull and brain size than their predecessors. They were also the first species of humans ever who were able to build their own shelters. This gave them a great deal of mobility because this, combined with their ability to easily live in areas with cold weather and temperatures, made them able to live in large areas of the planet!
Archaeological analysis of their bones suggests that this species lived between 1.9 to 1.8 million years ago. The fact that they lived so long ago seems to suggest that they were not as biologically advanced as more modern species of humans! Because archaeologists have not been able to find fossils of their skulls, they don’t know what the brain size of these humans was. They also don’t know what they looked like, both in terms of anatomy and physiology, or how much they weighed! They definitely looked like modern humans because they did not have the large muscle mass or australopithecine crania of primates, but they were different because their torsos were much narrower than the middle part of their bodies, and they had much narrower faces.
And here’s something startling
The recent finds of fossils of other species of humans and the discovery of transposons from other humans in human DNA suggests that different species of humans interbred with each other in the distant past. It has also left wide areas of debate in the argument of human origins, with some scientists wondering if all species of humans really evolved from primate species. In a controversial publication which initially appeared in the scientific academic journal the Icarus, a group of scientists suggested that extraterrestrials with an advanced knowledge of genetics, genetic engineering, and of life itself genetically engineered the different species of humans many millions of years ago. Furthermore, these scientists suggested that these aliens used human DNA as a way to code important information about life and the universe. Indeed, these scientists think that if aliens are communicating with humans, they are not doing so with signals from the universe, they are doing so with genetic messages imbedded deep in the genome. They were naturally challenged by mainstream scientists, but their findings and thoughts have sparked inquiry and thought in many scientists.
While we may never know our true origins, the findings presented below show that our evolutionary history has been an intertwined and complex one!