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  • Our ancestors mated with Denisovans

    Move over, Neanderthals: Our ancestors mated with Denisovans not once but twice, scientists say

    Amina Khan
    By AMINA KHAN
    MAR 15, 2018 | 12:35 PM
    Two waves of Denisovan and one wave of Neanderthal ancestry have shaped present-day humans. (Browning et al. / Cell)

    Humans weren't just making babies with Neanderthals back in the day. A new study that compares the genomes of different groups of modern humans has found that our ancestors interbred with another close relative, the Denisovans, more than once.

    The findings, published in the journal Cell, demonstrate a special method that scientists can use to find these hidden fragments of DNA from our long-gone cousins — and shed fresh light on the complexities of human evolution.

    Denisovans, close cousins of modern humans and Neanderthals, were first described in 2010 after the discovery of a fossil finger bone from a cave in the Altai mountains in Siberia. That roughly 41,000-year-old fossil allowed researchers to extract some of its DNA and sequence the genome of its former owner, a young female Denisovan.

    Those DNA samples revealed a number of matches in the genome of some modern humans — including a gene that helps Tibetans adapt to high-altitude environments. This means that at some point in time, modern humans and Denisovans had sex. The same goes for Neanderthals, whose DNA is also embedded in our own genome. (That ability to mate and produce viable offpsring is a large part of why some scientists are starting to avoid calling Neanderthals and Denisovans separate "species.")

    But it's difficult to learn a whole lot about the mark that Denisovans left on modern humans based primarily on the Altai Denisovan girl's finger bone. (There are only a handful of other fossils, mostly teeth and a toe, which means scientists don't have a great idea of what they looked like, either.)

    So for this paper led by Sharon Browning, a biostatistician at the University of Washington in Seattle, scientists tried another approach — one that could pick out Denisovan DNA without needing an ancient genome for reference. Her method compared modern human genomes from different regions (Europe, Asia and Oceania) to look for shared segments of DNA with telltale levels of genetic variation that indicated they came from an archaic human.

    The researchers found that Oceanian people, particularly Papuans, had the most Denisovan DNA — it made up about 5% of their genomes. East Asians were a distant second, with about 0.2%.

    But the odd thing about the East Asian DNA is that it held two genetically distinct groups of Denisovan DNA — one that was more related to the Altai Denisovan, and one that was far less similar. This meant that those two types of Denisovan DNA actually came from two different populations that had been separated over time, allowing random mutations to emerge and their lineages to diverge.

    "I definitely wasn't going and looking specifically for this," said Browning, who'd simply been looking to see if this statistical method would work. "It was a surprise when it popped out of the results."

    The scientists also found Neanderthal DNA using this method, though they didn't find two waves the way they did with the Denisovans.

    What this means for how humans and our fellow hominins moved around and interacted is unclear, Browning said. The scientists can't say which interaction happened first, although it does seem to imply that Denisovans had spread farther than previously thought.

    "It makes it clear that there were at least two populations living over an extended geographical distribution, whereas the only remains we have are from that one cave in Siberia," Browning said.

    It also strengthens the growing understanding that humans and their close relatives interacted with each other far more than we once thought.

    It "says something about them not being so different from us," she said.

    Browning said the next step is to apply this to other populations — perhaps in Africa, where there are few genomic sequences of archaic humans available — and to see whether other hints of ancient hominin matings show up.

  • #2
    Speaking of Science Humans bred with this mysterious species more than once, new study shows

    By Ben Guarino March 15 at 1:41 PM Email the author
    A family in a cave as depicted in an exhibit at Croatia's Neanderthal Museum. (Nikola Solic/Reuters)

    We rarely portray Neanderthals, our close relatives, as telegenic. Museum exhibits give them wild tangles of hair, and Hollywood reduces them to grunting unsophisticates. Their skulls suggest broad faces, tiny chins and jutting brows. But to mock Neanderthals is to mock ourselves: Homo sapiens had lots of sex with Homo neanderthalensis. Neanderthal genes supply between 1 percent and 4 percent of the genome in people from homelands on several continents, from Britain to Japan to Colombia.

    DNA from another human-like primate, the Denisovans, lurks in modern genomes, too. A molar and a chip of pinkie bone found in a Siberian cave provide what little information we have about this species. DNA extracted from the fragments previously revealed cross-species breeding. Yet a new study in the journal Cell shows the ancient hanky-panky did not stop in Siberia: Humans who traveled across South Asia mated with a separate group of Denisovans, as well.

    “This is a breakthrough paper,” said David Reich, who studies ancient DNA at Harvard University and was not involved with the study. “It's a definite third interbreeding event,” one that adds to the previously known Denisovan and Neanderthal mixtures.

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    2:25
    New fossils show closer link between humans and Neanderthals

    (© Javier Trueba/Madrid Scientific Films)

    Humans and Neanderthals divided into separate groups as far back as 765,000 years ago. Denisovans and Neanderthals were closer cousins who split more recently and then vanished — perhaps because we absorbed their lineages.

    Two waves of Denisovan ancestry have shaped present-day humans. (Browning et al. 2018/Cell)

    A team of scientists, led by University of Washington biostatistician Sharon R. Browning, took an approach that Reich called a “technical tour de force.” In the new study, Browning and her colleagues examined more than 5,500 genomes of modern humans from Europe, Asia and Oceania, looking for any possible archaic DNA.

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    “We’re looking for segments of DNA in an individual that look quite different from the rest of the variation in the population,” Browning said.

    After the team fished out the DNA variations, the researchers matched the segments to Denisovan and Neanderthal sequences, known from samples in Siberia's Altai Mountains.

    All groups studied, from British and Bengali people to Peruvians and Puerto Ricans, had a dense cluster that closely matched the Altai Neanderthals. Some populations also had a cluster that matched the Altai Denisovans, which was particularly pronounced in East Asians.

    The surprise was a third cluster — not like the Neanderthal DNA and only partially resembling the Altai Denisovans. This, the authors concluded, was a second and separate pulse of Denisovan genes into the DNA blender.

    3:52
    The Neanderthal survival game

    (Courtesy of Nature Video)

    “The geography is quite suggestive,” Browning said. The authors hypothesize that, as ancestral humans migrated eastward, they came across two different Denisovan populations. One pulse, to the north, shows up in people from China, Japan and Vietnam.

    The other Denisovan pulse appears to the south. “Maybe it was down in the southeast corner of Asia,” Browning said. “It could possibly have been on an island en route to Papua New Guinea, but we clearly don’t know.”

    Reich said he would not be surprised if methods similar to this one revealed additional mixtures. “I am sure there are others,” he said, considering the wide range of archaic groups across Eurasia.

    Browning plans to continue to hunt for additional mixtures, including among people of African descent who were excluded from this study because the warm continental climate makes finding archaic DNA a challenge.

    “We’re interested in other populations around the world, especially Africa,” she said.

    Comment


    • #3
      My 1999 Ford Ranger has four wheels just like a Rolls Royce.
      Also, common elements are the steering wheel, engine, brakes, transmission, headlights, tail lights, seats, and doors – even sun visors and a rear view mirror.
      Wow!
      My old Ranger has so much in common with a Rolls Royce it must have been made by the same company or maybe made from old Rolls Royce parts.

      Comment


      • #4
        Originally posted by glen smith View Post
        My 1999 Ford Ranger has four wheels just like a Rolls Royce.
        Also, common elements are the steering wheel, engine, brakes, transmission, headlights, tail lights, seats, and doors – even sun visors and a rear view mirror.
        Wow!
        My old Ranger has so much in common with a Rolls Royce it must have been made by the same company or maybe made from old Rolls Royce parts.
        That is not a valid comparison Glen. Your Ford does not share any common parts with a Rolls. Yes they are both cars and both have a steering wheel etc. But every part of the Ford is different then every part of the Rolls. The steering wheels are not the same etc. That would show they both came from different factories.

        But if you found that the Rolls had some parts marked "Ford", then you would know those parts came from Ford and Ford had some part in the making of the Rolls.

        Have you studied genes. I have taken a course from the University of Chicago on genes.

        There are segments of the DNA that are far different in men and in these animals that looked like men. ( they had no spirit )

        When certain segments from the Denisovans are seen in some of the DNA of men, it is strong evidence that this mating took place. It is like those parts marked Ford, but they are marked Denisovan.

        Also there is evidence in the Bible. Who did Cain mate with ? Who lived in the land of Nod ? Why was Cain, a total stranger, so quick to become the leader of this group ? How did Cain build a city if there were no other creatures on the earth ?

        Comment


        • #5
          More directly, an analogy using man made parts does not directly correspond to the natural process of biology.
          You are correct in pointing this out. And this would be accurate even if my Ranger was entirely made of parts from a Rolls Royce.

          What does apply from the analogy is the gene researchers predetermined idea that the same gene has the same source. Does it? You correctly point out that the Ranger does not have a Rolls Royce steering wheel. Any idiot ought to see that difference.

          On the other hand, when biologist suggest parallel evolutionary adaptations where plants or animals have the same adaptations they claim they are not the same source. Are scientists reading the evidence or interpreting the facts to become their evidence?

          Lou posted:
          Also there is evidence in the Bible. Who did Cain mate with ? Who lived in the land of Nod ? Why was Cain, a total stranger, so quick to become the leader of this group ? How did Cain build a city if there were no other creatures on the earth ?

          Reply: This is a biblical interpretation question not a science question.
          Accordingly, I have not an interest in answering your questions on this topic and subjecting divine revelation to scientific scrutiny. Lou may win the point that Cain mated with a Denisovan.
          Last edited by glen smith; March 18, 2018, 10:14 AM.

          Comment


          • #6
            Originally posted by glen smith View Post
            More directly, an analogy using man made parts does not directly correspond to the natural process of biology.
            You are correct in pointing this out. And this would be accurate even if my Ranger was entirely made of parts from a Rolls Royce.

            What does apply from the analogy is the gene researchers predetermined idea that the same gene has the same source. Does it? You correctly point out that the Ranger does not have a Rolls Royce steering wheel. Any idiot ought to see that difference.

            On the other hand, when biologist suggest parallel evolutionary adaptations where plants or animals have the same adaptations they claim they are not the same source. Are scientists reading the evidence or interpreting the facts to become their evidence?

            Lou posted:
            Also there is evidence in the Bible. Who did Cain mate with ? Who lived in the land of Nod ? Why was Cain, a total stranger, so quick to become the leader of this group ? How did Cain build a city if there were no other creatures on the earth ?

            Reply: This is a biblical interpretation question not a science question.
            Accordingly, I have not an interest in answering your questions on this topic and subjecting divine revelation to scientific scrutiny. Lou may win the point that Cain mated with a Denisovan.
            I did not claim that Cain mated with a Denisovan. I did post an article that made the claim and also put forth questions that asked who did Cain mate with.

            Comment


            • #7
              Originally posted by Lou Newton View Post

              I did not claim that Cain mated with a Denisovan. I did post an article that made the claim and also put forth questions that asked who did Cain mate with.
              Looking again, I see how Lou missed my humor that he wins the point that Cain mated with Denisovan
              because I missed Lou's point that he is thinking Cain could have possibly mated with a female Denisovan
              and joined Denisovan society until he restated that he did not claim that.
              So Lou's post is suggesting the possibility but not claiming:
              "Also there is evidence in the Bible."
              Cain mated with a femalw Denisovan and became the leader in Denisovan society?
              "Who did Cain mate with?"
              - Denisovan?
              "Who lived in the land of Nod?"
              - Denisovan?
              "Why was Cain, a total stranger, so quick to become the leader of this group?"
              - Adam's son is superior to Denisovan?
              "How did Cain build a city if there were no other creatures on the earth?"
              - There were Denisovan to do the work?

              Comment


              • #8
                Originally posted by glen smith View Post

                Looking again, I see how Lou missed my humor that he wins the point that Cain mated with Denisovan
                because I missed Lou's point that he is thinking Cain could have possibly mated with a female Denisovan
                and joined Denisovan society until he restated that he did not claim that.
                So Lou's post is suggesting the possibility but not claiming:
                "Also there is evidence in the Bible."
                Cain mated with a femalw Denisovan and became the leader in Denisovan society?
                "Who did Cain mate with?"
                - Denisovan?
                "Who lived in the land of Nod?"
                - Denisovan?
                "Why was Cain, a total stranger, so quick to become the leader of this group?"
                - Adam's son is superior to Denisovan?
                "How did Cain build a city if there were no other creatures on the earth?"
                - There were Denisovan to do the work?
                Hi Glen - The issue of who Cain mated with is quite a mystery. Thanks for your kind reply.

                Comment


                • #9
                  If Cain could have possibly mated with a female Denisovan the genetic evidence would place the date for Cain copulating back at 39,000 B.C. fitting in an old earth hypothesis and impossible for a young earth hypothesis.

                  Genesis 4 describes Cain as wandering 4:14 & 4:16 (The meaning of the Hebrew word "Nod" is to wander.)

                  Genesis 4:17
                  17 Later, Cain had sexual relations with his wife. She became pregnant and gave birth to Enoch. Cain founded a city and named it after his son Enoch.

                  Cain wandered "on the east of Eden," (verse 16) an expression which seems to mean adjoining Eden. Therefore, it was not far away. Here in due time Cain's son Enoch was born. As Adam's family increased in Eden, and Cain lived in fear that "everyone" there sought his life for slaying Abel, he could have hit upon an idea to enclose and "fortified" a residence, for self protection. This is the primary meaning of the word, "city" in Hebrew. It did not at first denote size, but an enclosed, fortified place. Cain may merely have erected a wooden palisade about a few huts, but this was new, it was novel, it deserved a name as the first such structure. He named it after his son, "Enoch."

                  Commenting on this verse, Dr. Arthur C. Custance relates the following.

                  "The subsequent history of this city we do not know. . . When cuneiform was being deciphered for the first time, it soon became apparent that some of the cities mentioned in Biblical antiquity were still in existence as mounds and very often the natives in the area had preserved the original name in a modified form. A very important city in antiquity appeared under the name Uruk and a study of cuneiform soon revealed that this could equally well be pronounced Unuk, which was recognized at once by Sayce, and many others, as identical with the Biblical word, Enoch.

                  The modern idea of a city built by hordes of Denisovans working for Cain is not necessary if the meaning of the Hebrew language is understood.

                  The Hebrew text of Genesis 4:17 is unclear.
                  Either Cain built a city and named it after Enoch, or else Enoch built a city named for himself.

                  Suggesting any understanding more than this is very speculative.

                  The question will always remain: How do we account for the wife for Cain?
                  We do not account for the wife for Cain since God did not see fit to reveal that information.
                  Just maybe, this is a quandary left as a test of who do we trust - men with their reason and skepticism or God.
                  Last edited by glen smith; March 20, 2018, 01:21 PM.

                  Comment


                  • #10
                    God did account for how the plants and animals came to be:

                    11 Then God said, “Let the land produce vegetation: seed-bearing plants and trees on the land that bear fruit with seed in it, according to their various kinds.” And it was so. 12 The land produced vegetation: plants bearing seed according to their kinds and trees bearing fruit with seed in it according to their kinds.

                    24 And God said, “Let the land produce living creatures according to their kinds: the livestock, the creatures that move along the ground, and the wild animals, each according to its kind.” And it was so

                    God does not use the word create for these two events.

                    Plus God left mankind many bones of animals that walked upright and looked like men. It is every bit as reasonable to think that God took one of these animals and breathed the breath of life (the Spirit ) into him ( Adam ) as any other belief. That would explain why God says He made Adam and He created Adam. It could mean that God had the earth bring forth Adam's body and soul and then God created the spirit for Adam and Adam became a man.

                    But when God banished Cain there were only two other people that existed, Adam and Eve. God not only does not list any sister of Cain that was born, but does not tell of Cain taking anyone with him. But after Cain goes to a new land a wife is listed.

                    When Abraham leaves Ur it is told who he took with him. When Noah goes into the Ark, it is told who goes with him.

                    Can we eliminate the possibility that God may have made a wife for Seth, the same way He made a wife for Adam ?

                    Comment


                    • #11
                      Everything is on the table because we do not know, but that everything is speculation not divine revelation. We might as well speculate aliens from another planet, other creative acts of God, humanoids descended by the process of biological evolution, humanoids descended by the process of theistic evolution, or the creation story is an analogy or mythological. Ones perspective depends upon ones view of what is divine revelation and who is God.

                      The divine revelation of how God created Adam is very specific.
                      Genesis 1:27
                      God created male and female in his own image -
                      The mechanics of how God made man is also very specific.
                      Genesis 2:7
                      7 then the Lord God formed the man of dust from the ground and breathed into his nostrils the breath of life, and the man became a living creature.

                      Here are three identifying elements of how God formed a living being also translated living soul.
                      1. formed from the dust of the earth which is supposedly the physical body without life.
                      2. breathed (spirited) into man's nostrils the breath (spirit) of life - In biblical Hebrew the words breath and spirit are the same word.
                      The life provided by the spirit is the breath or spirit of God. Life, breath, or spirit is of God and is not created and does not ever belong to man. Therefore, it seems life, breath, or spirit being provided by God must return to God at death.
                      3. The physical body (made of the dust of the earth) and the breath of God become a living creature or living souls.

                      In Genesis 46:27 various English version translate the Hebrew word that should be translated as "soul" in a couple of different ways - either as persons or family members, but the correct translation is souls.
                      Genesis 46:27 WEB
                      The sons of Joseph, who were born to him in Egypt, were two souls. All the souls of the house of Jacob, who came into Egypt, were seventy.

                      It was neither lifeless physical bodies or soulish spirits without bodies that were in Egypt, but seventy (70) souls were in Egypt. What God made in Genesis 2:7 was a soul which is composed of fleshly body and the spirit of God. Death is when the life giving breath of God leaves the body formed from the elements (dust) of the earth. Thinking like a Greek philosopher is why the New Testament is understood and translated as representing the composition of man as threefold - body, soul, and spirit - as if man is something apart from the on going actions of God. Any level of consciousness after death of either the condemned or the redeemed originates because of divine action rather than because man possesses something everlasting. All souls must have a body, physical or spiritual, plus the breath of God.

                      Understanding the composition of man is one element of the ancient Hebrew worldview.
                      This is invaluable in understanding the New Testament.

                      Comment


                      • #12
                        Non biblical sources for dating Genesis 25

                        Dating the Genesis texts before the flood stirs controversy, but by the date when God called Abram at the start of Genesis 12, this date is close enough to the verifiable secular latest possible date for Genesis 25 that retracing the timeline to Abram is not such a stretch.

                        The Hebrew word Edom means "red", and is derived from the name of its legendary founder, Esau, the elder son of the Hebrew patriarch Isaac, because he was born "red all over" (Genesis 25:25). As a young adult, he sold his birthright to his brother Jacob for "red pottage" (Genesis 25:29-34). The Old Testament describes the Edomites as descendants of Esau.

                        Edom is mentioned in the Hebrew Bible and also in a list of the Egyptian pharaoh Seti I from c. 1215 BC and in the chronicle of a campaign by Ramses III (r. 1186–-1155 BC).1 The Edomites, who have been identified archaeologically, were a Semitic people who probably arrived in the region around the 14th century BC.1 Archaeological investigation showed that the country flourished between the 13th and the 8th century BC and was destroyed after a period of decline in the 6th century BC by the Babylonians.1 After the loss of the kingdom, the Edomites were pushed westward towards southern Judah by nomadic tribes coming from the east; among them were the Nabateans, who first appeared in the historical annals of the 4th century BC and already established their own kingdom in what used to be Edom, by the first half of the 2nd century BC.1 More recent excavations show that the process of Edomite settlement in the southern parts of the Kingdom of Judah and parts of the Negev desert down to Timna had started already before the destruction of the kingdom by Nebuchadnezzar II in 587/86 BCE, both by peaceful penetration and by military means and taking advantage of the already-weakened state of Judah. 2 & 3


                        Footnotes

                        1. Avraham Negev; Shimon Gibson (2001). Edom; Edomites. Archaeological Encyclopedia of the Holy Land. New York and London: Continuum. pp. 149–150. ISBN 0-8264-1316-1.

                        2. Prof. Itzhaq Beit-Arieh (December 1996). "Edomites Advance into Judah". Biblical Archaeology Review. Retrieved 8 December 2015.

                        3. Jan Gunneweg; Th. Beier; U. Diehl; D. Lambrecht; H. Mommsen (August 1991). "'Edomite', 'Negbite'and 'Midianite' pottery from the Negev desert and Jordan: instrumental neutron activation analysis results". Archaeometry. Oxford, UK: Oxford University.

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