Scientists studying bones from a cave used by both Neanderthals and the current human model found DNA from a girl who was 'none of the above.' She's from a previously-unknown species, or sub-species, of human
Other scientists discovered that chimpanzees communicate in an unexpectedly 'human' way.
We live in an exciting era: or a disturbing one, depending on a person's assumptions and preferences.
- Human Ancestry: It's Complicated
- Communication: One Chimp to Another
- Denisovan Descendants
(From Captain Blood at de.wikipedia, via Wikimedia Commons, used w/o permission.)
(Topographic map of Central Asia, including the Altai mountains.)
Denisovans lived in or near the Altai mountains about 41,000 years before we started playing baseball. Some scientists call them a different species, others say they're a subspecies of homo sapiens sapiens. Either way, they're part of the human family.
We don't know much about the Denisovans yet, apart from a bit of finger bone, two teeth, and a toe bone. That's not much to work with: but scientists found intact DNA in the bones: enough to trace Denisovan descendants among Melanesians and Aboriginal Australians. The odds are pretty good that many or most folks in southern and southeast Asia are related to Denisovans.
This might be a hoax, like the Piltdown Man, the Cardiff giant, and Archaeoraptor: but I don't think so. Too many different scientists agree that Denisovan DNA is about 41,000 years old, is different from other human populations, and shows up in folks living today. (March 7, 2014)
Denisovans seem to have been as open-minded in one way as my ancestors were. About 17% the Denisovan DNA we found is from local Neanderthal populations: and some is from another variety of human we didn't know about before.
(From Rick Potts, Susan Antón and Leslie Aiello; via the Smithsonian, used w/o permission.)
(One of humanity's many migrations.)
I'm not surprised that Denisovans didn't seem concerned with 'racial purity.' As I see it, they were people acting like humans.
Over the last few million years, we've moved around: a lot. Each time we do, some of the newcomers' younger generation is likely to take a lively interest in local lads and lasses: to the occasional dismay of 'proper' parents. (July 6, 2014; December 13, 2013)
Considering the attitude some of my ancestors had toward another set of my forebears, I'm not inclined to be upset at the thought of folks not emulating the Hapsburgs, and that's another topic. (December 13, 2013)
As for what we're learning about humanity's past, I could get upset that God didn't take a 17th century Englishman's beliefs into account when designing the universe: but I would much rather take reality 'as is.' (February 5, 2014)
"3 Terrible and awesome are you, stronger than the ancient mountains."My faith isn't threatened by knowledge that Earth has been around for about 4,540,000,000 years, and that life began here at least 3,600,000,000 years back. If anything, the immense scale of this universe enhances my appreciation for God's power: and patience. (July 4, 2014; October 13, 2013)
"Yours are the heavens, yours the earth; you founded the world and everything in it."
"Your throne stands firm from of old; you are from everlasting, LORD."
(From Joseph Graham, William Newman, and John Stacy; via USGS and Wikimedia Commons; used w/o permission.)
As a Catholic, I'm obliged to believe that God creates everything: and that humanity is made "in the image of God." (Genesis 1:27; Catechism of the Catholic Church, 355)
That doesn't mean I believe that God looks like the floating fellow in Michelangelo's "The Creation of Adam." I've discussed science, evolution, and secondary causes before. (October 4, 2013)
We're made of the same stuff as the rest of the universe: clay, as Genesis puts it.
"2 the LORD God formed man out of the clay of the ground and blew into his nostrils the breath of life, and so man became a living being."We're living creatures, "male and female," as Genesis 1:27 says. We're designed as physical and spiritual creatures, animals who are people. (Catechism, 356-370, 1951)
I like being this sort of creature. More to the point:
"God looked at everything he had made, and he found it very good. Evening came, and morning followed - the sixth day."
The notion that humans have nothing at all in common with other animals is persistent. I suspect that it's related to a dualistic attitude running through Western civilization: the belief that 'spiritual' is good, but 'physical' is bad. (June 3, 2012)
On the other hand, quite a few folks seem quite comfortable with recognizing our connections with the rest of the universe.
Long before my civilization settled into its current form, folks had noticed similarities between humans and animals. I'm pretty sure that's why so many cultures have a tradition of beast fables like the fox and the grapes and the tortoise and the hare.
I like fables, but I also appreciate Mark Twain observation of an 'industrious' ant:
(From "A Tramp Abroad," Mark Twain/Samuel Clemens; via gutenberg.org; used w/o permission.)
"...I measured the ground which this ass traversed, and arrived at the conclusion that what he had accomplished inside of twenty minutes would constitute some such job as this—relatively speaking—for a man; to wit: to strap two eight-hundred-pound horses together, carry them eighteen hundred feet, mainly over (not around) boulders averaging six feet high, and in the course of the journey climb up and jump from the top of one precipice like Niagara, and three steeples, each a hundred and twenty feet high; and then put the horses down, in an exposed place, without anybody to watch them, and go off to indulge in some other idiotic miracle for vanity's sake...."As we learn more about this universe, we're discovering that even bacteria can act in unexpectedly organized ways.
("A Tramp Abroad," Mark Twain, via gutenberg.org)
Bacillus subtilis shows up in Earth's soil, and fairly often in human digestive tracts. Put these bacteria in a drop of water, and they'll start swimming in circles: bacteria near the edge swimming one direction, those near the center swimming the opposite way.
Enkeleida Lushi and other researchers think they've got an explanation for this oddly-organized behavior. A computer simulation showed that when bacteria along the edges of a bit of water swim one way, they push water backward, forcing bacteria on the inside track to swim the other way.
More about these bacteria:
- "Bacterial Vortex: Microbes' Odd 'Swimming' Behavior Explained"
Tanya Lewis, LiveScience (June 23, 2014)
(From Chip Clark, Smithsonian Human Origins Program (left three); Guram Bumbiashvili, Georgian National Museum (right); via LiveScience, used w/o permission.)
("Three early human species likely co-existed at the dawn of humanity between 2.1 million and 1.8 million years ago, including the 1470 group (likely Homo rudolfensis) and the 1813 group, likely Homo habilis, (left and second from left, respectively). The other fossils represent Homo erectus, which evolved by 1.8 million to 1.9 million years ago."
"How Evolving Traits Helped Humans Survive Unstable World" Charles Q. Choi, LiveScience (July 3, 2014)Scientists figured that a steadily cooling climate in our east African homeland was linked to human evolution. As we learned more about the last few million years, the picture got more complicated.
"Three different human species may have walked the Earth at the dawn of the human lineage, dividing up their environment in slightly different ways, and the ancestors of modern humans may have survived because of traits such as large brains that helped them adapt to unstable, shifting landscapes, researchers say.
"Moreover, the defining features of the human lineage may not have evolved together gradually at once, but piecemeal in stages over millions of years, scientists added.
"Modern humans, Homo sapiens, are the only living members of the human lineage, the genus Homo, which is thought to have arisen in Africa more than 2 million years ago. Many now-extinct human species were thought to once roam the planet, such as Homo erectus, the first to regularly keep the tools it made. [Gallery: See Photos of Humans' Closest Ancestor]
"Many traits unique to the human lineage were long thought to have originated between 2.4 million and 1.8 million years ago in Africa. These include a large brain and body, long legs, reduced differences between the sexes, increased meat-eating, prolonged maturation periods, increased social cooperation and tool making.
"However, recent fossil evidence suggests these traits did not arise together as a single package. Instead, key human features evolved piecemeal at separate times, with some emerging substantially earlier and some later than previously thought. For instance, recent findings suggest long legs, a feature once considered unique to humans, developed in earlier ancestors, the genus Australopithecus, between 3 million and 4 million years ago, and stone tools about 2.6 million years old may predate the origin of Homo...."
The current ice age, the Pliocene-Quaternary glaciation, started about 2,580,000 years back. The last I heard, scientists aren't sure whether this ice age is finally over: or if we're in one of the interglacial periods.
Even in the depths of the Pliocene-Quaternary ice age, continental glaciers haven't reached the equator. But from 2,500,000 to 1,500,000 years ago — our very remote ancestors either survived in an unstable climate, enduring droughts and floods, heat and cold; or not.
It looks like versatility became a vital survival skill when our environment became unstable. We're descended from uncounted generations of folks who learned to cope.
(From Rick Potts, Susan Antón and Leslie Aiello, via the Smithsonian, used w/o permission.)
(Humanity's evolution from 3,000,000 to 1,500,000 years ago, showing how we adapted to a changing world.)
More about being human in a changing world:
- "Climate Effects on Human Evolution"
Smithsonian Museum of Natural History
- "Timeline of human evolution"
- "Human Characteristics: What Does it Mean to be Human"
Smithsonian Museum of Natural History
(From Hobaiter and Byrne, via BBC News, used w/o permission.)
"Chimpanzee language: Communication gestures translated"I speak American English, and hadn't run into the phrase "budge up" before. Cambridge Dictionaries Online say that it's British English for 'please move, make room for me.'
Victoria Gill, BBC News (July 3, 2014)
"Researchers say they have translated the meaning of gestures that wild chimpanzees use to communicate.
"They say wild chimps communicate 19 specific messages to one another with a 'lexicon' of 66 gestures.
"The scientists discovered this by following and filming communities of chimps in Uganda, and examining more than 5,000 incidents of these meaningful exchanges....
"...Dr Catherine Hobaiter, who led the research, said that this was the only form of intentional communication to be recorded in the animal kingdom.
"Only humans and chimps, she said, had a system of communication where they deliberately sent a message to another individual.
" 'That's what's so amazing about chimp gestures,' she told BBC News.
" 'They're the only thing that looks like human language in that respect.'..."
In my dialect, "to budge" means "to move," but I'd say things like "it won't budge," or "he won't budge." I wouldn't say "budge over" to someone, not unless I was being brusk or disrespectful: and that's yet another topic.
Using a light nudge with the back of the hand to express that idea makes sense: which shouldn't be surprising, since humans and chimps are very much alike. (March 22, 2013)
What's really remarkable here isn't that chimps use gestures to communicate with other chimps. Many animals share information through gesture or movement, like the waggle dance a honey bee uses to tell the hive where a food source is.
These researchers have shown that a chimp can communicate an idea to a specific individual. That's much closer to human behavior than a honey bee passing information along to every other bee in sight. I don't think we need to reconsider limiting voting rights to humans, though.
(From C. Hobaiter, via BBC News, used w/o permission.)
("Chimps will check to see if they have the attention of the animal with which they wish to communicate"
"...In one clip, a mother presents her foot to her whimpering offspring, signalling: 'Climb on me.' The youngster immediately jumps on to its mother's back and they travel off together.I've run into folks who seem to feel "set apart" from the rest of God's creation. Maybe it feels more "spiritual" to pretend that physical reality is nasty, and that humans aren't supposed to have biological functions. That doesn't make sense. Not to me. (November 27, 2011; August 31, 2011)
" 'The big message [from this study] is that there is another species out there that is meaningful in its communication, so that's not unique to humans,' said Dr Hobaiter.
" 'I don't think we're quite as set apart as we would perhaps like to think we are.
" 'But then chimps are more closely related to us than they are to the rest of the great apes, so it makes sense that we are incredibly similar to them in many ways.'..."
(Victoria Gill, BBC News)
Human beings are animals. We're a special sort of animal, endowed with reason, with free will. We're also people. We're made in the image of God: rational, with free will. (Catechism of the Catholic Church, 1951, 1700-1706, 1730)
That freedom comes with personal responsibility, and that's yet again another topic. (Catechism, 1731-1742)
Let's see what another scientist said about chimps, communication, and being human.
"...Dr Susanne Shultz, an evolutionary biologist from the University of Manchester, said the study was commendable in seeking to fill the gaps in our knowledge of the evolution of human language. But, she added, the results were 'a little disappointing'.I'm pretty sure that we have more to learn about how chimps communicate. But my guess is that we won't discover that they've been discussing their equivalent of the Aristotelian mean and Plato's cave.
" 'The vagueness of the gesture meanings suggest either that the chimps have little to communicate, or we are still missing a lot of the information contained in their gestures and actions,' she said.
" 'Moreover, the meanings seem to not go beyond what other less sophisticated animals convey with non-verbal communication.
" 'So, it seems the gulf remains.' "
(Victoria Gill, BBC News)
"Tibetan altitude gene inherited 'from extinct species' "Denisovans lived in Asia, not all that far back. The Denisovan girl whose DNA we've analyzed lived about 41,000 years ago, in or near the Altai Mountains, where today's Russia, China, Mongolia and Kazakhstan come together.
Paul Rincon, BBC News (July 2, 2014)
"A gene that allows present-day people to cope with life at high altitude was inherited from an extinct species of human, Nature journal has reported.
"The variant of the EPAS-1 gene, which affects blood oxygen, is common in Tibetans - many of whom live at altitudes of 4,000m all year round.
"But the DNA sequence matches one found in the extinct Denisovan people.
"Many of us carry DNA from extinct humans who interbred with our ancestors as the latter expanded out of Africa.
"Both the Neanderthals - who emerged around 400,000 years ago and lived in Europe and western Asia until 35,000 years ago - and the enigmatic Denisovans contributed DNA to present-day people...."
I'm descended from northwestern Europeans, so I'm more likely to have Neanderthals in the family tree: but learning that I might have Denisovan forebears wouldn't shock me.
Granted, I've got a delicate frame compared to Neanderthals and Denisovans: but change happens. My family lost the signature wry mouth of my Campbell ancestors a few generations back, and that's still another topic. Topics. (December 13, 2013; May 15, 2012)
(From Max Planck Institute for Evolutionary Anthropology, via BBC News, used w/o permission.)
("A tiny finger bone provided a high-quality DNA sequence for a new species - the Denisovans"
"...The Denisovans are known only from DNA extracted from the finger bone of a girl unearthed at a cave in central Siberia. This 40,000-50,000-year-old bone fragment, as well as a rather large tooth from another individual, are all that is known of this species.All humans produce more red blood cells when we spend time at very high altitudes. That's good news and bad news: with more red cells, our blood carries more oxygen; but most of us produce too many red cells. Our blood becomes too thick, blood pressure goes up, and raises our blood pressure, we're more likely to suffer strokes and, if we're pregnant, pre-eclampsia.
"The tiny 'pinky' bone yielded an entire genome sequence, allowing scientists to compare it to the DNA of modern people in order to better understand the legacy of ancient interbreeding.
"Now, researchers have linked an unusual variant of the EPAS1 gene, which is involved in regulating the body's production of haemoglobin - the molecule that carries oxygen in the blood - to the Denisovans. When the body is exposed to the low oxygen levels encountered at high elevations, EPAS1 tells other genes in the body to become active, stimulating a response that includes the production of extra red blood cells.
"The unusual variant common among Tibetans probably spread through natural selection after their ancestors moved onto the high-altitude plateau in Asia several thousand years ago...."
(Paul Rincon, BBC News)
Denisovan DNA apparently lets our bodies boost the red cell count to useful levels: and stop before we get too much. Small wonder that folks living in Tibet are so much more likely to have EPAS1 in their coding.
One more thing about Denisovans, Neanderthals, and us, all the recent versions of humanity — each of these groups lived recently, no more than a few dozen millennia back, often in the same areas.
Maybe we really are different "species" in the old Linnaean sense. I think it's more likely that Neanderthals, Denisovans, Germans, Polynesians, and all the rest of us are a single species: and that ethnicity has been sifting over the generations. (December 13, 2013)
- "Lukewarm Dinosaurs, the Earliest Known Fish, and Durable Faces"
(June 20, 2014)
- "Cave Men, Sea Monsters, Dead Scorpions, and Theoretical Physics"
(January 31, 2014)
- "Will the Real Neanderthals Please Stand Up?"
(December 20, 2013)
- "Truth, Toothpicks, Beaks, and God"
(December 13, 2013)
- " 'In a State of Journeying' "
(January 18, 2012)