A Caveman on the Prowl
Grogg is not going out to hunt and gather
But to see if he can find a mate he’d rather
He doesn’t even need to think of some line
As a hard conk on the head will do just fine
By Elton Camp (2011)
Where do we come from? In
this case, I don't mean “we” as in our great-great ancestors. I
mean how and where did human beings originate? You know, way back.
Not getting into arguments about the Bible origins, scientists estimate modern humans have been around for about 350,000 years. In that time, we have continued to evolve and our DNA has changed – but, only a small percentage of our genome may be unique to us.
Nathan Schaefer at the University of California, San Francisco, and his colleagues created a tool called the Speedy Ancestral Recombination Graph Estimator (SARGE), which allowed them to estimate the ancestry of individuals.
Schaefer says …
“The genetic tweaks that make humans uniquely human may come in small parcels interspersed with DNA inherited from extinct ancestors and cousins.
“Only 1.5 percent to 7 percent of the collective human genetic instruction book, or genome, contains uniquely human DNA, researchers report in Science Advance.
“We also find evidence of multiple bursts of adaptive changes specific to modern humans within the past 600,000 years involving genes related to brain development and function.”
(Nathan K. Schaefer et al. “An ancestral recombination graph of human, Neanderthal, and Denisovan genomes.” Science Advances. Vol 7, Issue 29. July 16, 2021.)
The big conclusion = Just 7% of our genome is uniquely shared with other humans, and not shared by other early ancestors, "This kind of finding is why scientists are turning away from thinking that we humans are so vastly different from Neanderthals."
The results don’t mean that individual people are mostly Neanderthal or Denisovan, or some other mix of ancient hominid. On average, people in sub-Saharan Africa inherited 0.096 percent to 0.46 percent of their DNA from ancient interbreeding between their human ancestors and Neanderthals, the researchers found (SN: 4/7/21). Non-Africans inherited more DNA from Neanderthals: about 0.73 percent to 1.3 percent. And some people inherited a fraction of their DNA from Denisovans as well.
The research does show that the exact form taken by that small amount of Neanderthal DNA varies from individual to individual – meaning two people can both have 2 per cent Neanderthal DNA but share little Neanderthal DNA in common. These differences add up, says Shaefer. Some estimates suggest about 40 per cent of the Neanderthal genome can be pieced together by combining genetic information from a wide variety of living people.
(Nathan K. Schaefer et al. “An ancestral recombination graph of human, Neanderthal, and Denisovan genomes.” Science Advances. Vol 7, Issue 29. July 16, 2021.)
The findings underscore "that we're actually a very young species," says Joshua Akey, who co-authored a paper in 2014 showing that modern humans carry some remnants of Neanderthal DNA. Since then, scientists have continued to refine techniques to extract and analyze genetic material from fossils. Akey concludes, "Not that long ago, we shared the planet with other human lineages."
Note:
Neanderthals were very early (archaic) humans who lived in Europe and Western Asia from about 400,000 years ago until they became extinct about 40,000 years ago. Denisovans are another population of early humans who lived in Asia and were distantly related to Neanderthals.
Neanderthals were stocky hunters adapted to Europe’s cold steppes, their enigmatic cousins Denisovans inhabited Asia, while the more primitive Homo erectus lived in Indonesia, and Homo rhodesiensis in central Africa.
Another study – Sikora et al. – reports about genome sequences from four early humans buried close together in western Russia about 34,000 years ago. The individuals clustered together genetically and came from a population with a small effective size, but they were not very closely related. Thus, these people may represent a single social group that was part of a larger mating network, similar to contemporary hunter-gatherers. The lack of close inbreeding might help to explain the survival advantage of anatomically modern humans.
(Martin Sikora. “Ancient genomes show social and reproductive behavior of early Upper Paleolithic foragers.” Science. Vol 358, Issue 6363. November 03, 2017.)
The Sunghir burials gave Sikora a chance to test his hypothesis that early humans developed a form of social structure that allowed early modern humans to swap partners and genes.
Sikora’s team calculated that about 300 people would need to be having sex with each other to produce so much genetic variation. That’s a much bigger population than these Stone Age people were probably traveling with, Sikora says. But it is possible that smaller groups were embedded in a larger social network where people had sex and exchanged ideas. This would have kept people from becoming as inbred as the Altai Neanderthal, or as genetically homogenous as the Vindija Neanderthal, which was the consequence of living in isolated groups.
The distribution of cultural artifacts and tools across Eurasia backs that up, says Erik Trinkaus, an anthropologist at Washington University, St. Louis who wrote a book on the Sunghir burials. “During this time period, people were covering huge distances. It’s not unusual to find materials 300 or 400 kilometers away from where they came from,” Trinkaus says.
Other research reports about a female who died around 90,000 years ago who was found to be half Neanderthal and half Denisovan, according to genome analysis of a bone discovered in a Siberian cave. This is the first time scientists have identified an ancient individual whose parents belonged to distinct human groups. The findings were published on 22 August in Nature.
(Viviane Slon et al. “The genome of the offspring of a Neanderthal mother and a Denisovan father.” Nature. 561. August 22, 2018.)
Who Was Doing What With Whom?
Sex for early humans and Neanderthals? Senior Journalist at BBC_Future, freelance science writer, and 2021 award winner Zaria Gorvett speculates …
“Their eyes met across the rugged mountain landscape of prehistoric Romania.
"He was a Neanderthal, and stark naked apart from a fur cape. He had good posture and pale skin, perhaps reddened slightly with sunburn. Around one of his thick, muscular biceps he wore bracelet of eagle-talons. She was an early modern human, clad in an animal-skin coat with a wolf-fur trim. She had dark skin, long legs, and her hair was worn in braids.
“He cleared his throat, looked her up and down, and – in an absurdly high-pitched, nasal voice – deployed his best chat-up line. She stared back blankly. Luckily for him, they didn’t speak the same language. They had an awkward laugh and, well, we can all guess what happened next.”
(Zaria Gorvett. “Here's what we know sex with Neanderthals was like.” BBC Future. January 13, 2021.)
Whether Zaria got her story right or not; however, we do know folks back then did “get together.”
There is even evidence from 13 Neanderthals found at El Sidrón in north-west Spain involving the genetic signature of a bacteria-like microorganism, Methanobrevibacter oralis is still found in our mouths to this day.
Relate this finding to sex? Laura Weyrich – an anthropologist at Pennsylvania State University explains that one possible route for the transfer is kissing. “When you kiss someone, oral microbes will go back and forth between your mouths,” she says. “It could have happened once but then sort of been somehow magically propagated, if it happened that the group of people who were infected went on to be very successful. But it could also be something that occurred more regularly.”
(Ewen Callaway. “Neanderthal tooth plaque hints at meals – and kisses.” Nature. Volume 543. March 09, 2017.)
Who had sex with whom?
One piece of scientific data that will help clear up whether these encounters were consensual or not would be the direction of the gene flow. That is, whether it was Neanderthal males impregnating human females, or human males impregnating Neanderthal females. The former would suggest that we were less conquering tyrants and more open-minded lovers. This is an open question in the science.
Researchers say the evidence of "strong gene flow” between Neanderthals and early modern humans suggest that as Neanderthal numbers dwindled towards the end of their existence, their Y chromosomes may have gone extinct, and been replaced entirely with our own. This suggests that a substantial number of ancestral human men were having sex with female Neanderthals.
(James Lloyd. Neanderthals lost their Y chromosome to modern humans.” Science Focus. October 01, 2020.)
Sexual Hardware
Yes, there is research about the nether regions of the human anatomy. Human penises are unusual is that they are smooth. Our closest living relatives, common and bonobo chimpanzees – with whom we share around 99% of our DNA – have “penile spines.” These tiny barbs, which are made from the same substance as skin and hair (keratin), are thought to have evolved to clear out the sperm of competing males, or to lightly chafe the female’s vagina and put her off having sex again for a while. (I know you are either laughing or violently shaking your innocent heads right now. Hey, this is science.)
Back to the penis information. In 2013, scientists discovered that the genetic code for penile spines is lacking from Neanderthal and Denisovan genomes, just as it is from modern humans, suggesting that it vanished from our collective ancestors at least 800,000 years ago. This is significant, because penis spines are thought to be most useful in promiscuous species, where they may help males to compete with others and maximise the chances of reproducing. This has led to speculation that – like us – Neanderthals and Denisovans were mostly monogamous.
(Philip L. Reno et al. “A Penile Spine/Vibrissa Enhancer Sequence Is Missing in Modern and Extinct Humans but Is Retained in Multiple Primates with Penile Spines and Sensory Vibrissae.” PLoS One. 8. 2013.)
There is not much evidence on the soft tissue anatomy of female Neanderthals. Human females are one of the few species that don’t have an obvious outward display to show they are ovulating. Scientists believe Neanderthals were probably were the same – Neanderthals would show the human-like pattern of concealed ovulation.
Promiscuous?
However, there’s some evidence to suggest that Neanderthals did sleep around more than modern humans. Humans are broadly monogamous. Researchers suggested that there might be a link between a species’ digit ratio and sexual strategy.
Digit rate is a measure of how the lengths of their index finger and ring fingers compare, calculated by dividing the first by the second. In a higher-testosterone environment, people tend to end up with lower ratios. This is true regardless of biological sex.
If scientists are right, Neanderthals – who had ratios in between the two groups (0.928) – were slightly less monogamous than both early modern and present-day humans.
(S.Lutchmaya et al. “2nd to 4th digit ratios, fetal testosterone and estradiol. Early Human Development.” Volume 77, Issues 1–2. April 2004.)
Once a Neanderthal-early-modern-human couple had found each other, they may have settled down near where the man lived, with each generation following the same pattern. Genetic evidence from Neanderthals suggests that households were composed of related men, their partners and children. Women seemed to leave their family home when they found a partner.
Another insight into happily-ever-after scenarios between early modern humans and Neanderthals comes from a study of the genes they left behind in Icelandic people today. An analysis of the genomes of 27,566 such individuals revealed the ages that Neanderthals tended to have children: while the women were usually older than their early modern human counterparts, the men were generally young fathers.
(Laurits Skov. “The nature of Neanderthal introgression revealed by 27,566 Icelandic genomes.” Nature. April 22, 2020.)
The Big Question: Could a Human And a Neanderthal Fall In Love?
Remember, evidence shows this was a time when you lived your whole life perhaps never knowing more than a few dozen people. Anywhere you traveled, you traveled on foot. The world must have seemed impossibly immense.
Brian Resnick, science reporter at Vox.com. Says, “Meeting a Neanderthal must have been an uncanny experience: like Star Trek characters encountering Vulcans for the first time. Here’s a species that looks remarkably like us, but it is not us.”
"If you think about what it’s like when you see a chimpanzee up close, you feel this immediate sense of kinship; you recognize a lot of its mannerisms and see things in its face. Neanderthals would have been 10 times as much like us as chimps," Adam Siepel, a genetics researcher at the Cold Spring Harbor Laboratory says. "There would have been a strong feeling of kinship, but there would have also been a strong sense of otherness."
(Brian Resnick. “Humans and Neanderthals had sex. But was it for love?” Vox. February 14, 2017.)
Human history suggests there are two options: We would have empathized with them, or we would have met them with aggression.
"When we look at history and see what Australian aboriginals went through, what Native American people went through, what Easter Islanders went through, it’s hard to say that the Neanderthals would have been better off than these historical cases," says John Hawks, University of Wisconsin anthropologist. "It’s probably the case that Neanderthals went through the Paleolithic version of the contacts we know about through history." (It could also be the case, Hawks says, that we just didn’t really notice Neanderthals were different from us.)
Horrors like the Holocaust, the Rwandan genocide, and so many other atrocities show how easily humans can dehumanize humans. What would we do to an entirely different species easily mistaken as an inferior?
But there is a case to be made that we might have been compassionate toward them.
It’s generally thought that humans have been essentially the same, in terms of biology, for around 200,000 years. We can project ourselves onto the people of the past because they are us. And that can give us hope to root for human-Neanderthal true love. "We all know people who have tragic love stories, and people who are very happy and contented their whole lives with one partner, and I imagine that we’re not looking at anything different in the past," Hawks says.
(And while one theory of Neanderthal extinction is that they died by our hands, their population numbers were already in decline by the time we encountered them. So maybe we didn’t kill them. Some scientists say we absorbed them).
(Brian Resnick. “Humans and Neanderthals had sex. But was it for love?” Vox. February 14, 2017.)
Conclusions
Neanderthals and humans? Sex – yes. Love – maybe. If the two species were swapping spit and sharing semen, what is not to think about them also sharing love?
Do you want a parallel? If you know bonobos at all, you understand they are the closest extant (surviving) relative to humans
Bonobos seem to live by the principle “make love, not war.” They are very docile towards one another, never aggressive or murderous, and possess many of the psychological traits we value most, including altruism, compassion, empathy, kindness, patience and sensitivity.
Imagine my shock when I read the following article from The Guardian written by Vanessa Woods – Australian science writer, author and journalist – who speaks of her husband falling in love … with a vixen bonobo.
Bonobos fetch up to $15,000 on the black market, and the story goes that Malou, the female bonobo, was on her way to end up as someone’s pet in a cage in Russia. When airport officials discovered her, they almost euthanised her. But luck was on her side, and she was sent back to where she came from, the Democratic Republic of Congo. Her mother had been shot for bushmeat, so Malou could not have survived in the wild.
Instead, Malou arrived at Lola Ya Bonobo, the only bonobo sanctuary in the world and home to more than 60 orphans just like her. Vanessa explains that her husband and her were there studying how their minds were both similar and different to ours.
Allow me to share this peculair love story …
“She had glossy black hair and eyelashes that arrived a minute before she did. She sashayed past me, threaded her fingers through my husband’s hair, and let her eyes work their magic. He was gone. Her name was Malou, and she had been found stuffed in someone’s hand luggage on the x-ray machine at an airport in Paris.
“Falling in love with a bonobo is not like falling in love with a dog or a fish. As our closest living relatives, sharing 98.7% of our DNA, bonobos don’t just look human, they practically are human. They have fingernails and walk on two legs. The females have breasts.
“And they have sex. A lot of sex. Missionary, doggy style, blossoming flower, butterfly and about a hundred more positions you have never heard of. Malou was only five, but she could have any male she wanted, including mine. “He’s mine, you little hussy,” I hissed, furiously tapping my engagement ring. In response, Malou looked at me, jumped on my shoulders and kicked me in the head.
“Bonobo love is like a laser beam. They stop. They stare at you as though they have been waiting their whole lives for you to walk into their jungle. And then they love you with such helpless abandon that you love them back. You have to love them back.
“I should explain that my husband Brian is, first and foremost, a scientist. I had been having my own love affairs with the bonobos in the nursery for years, and he always rolled his eyes. He loved bonobos for their minds. For what they could tell him about life’s great questions – what did it mean to be human? How could bonobos make us more human than we are?
It turns out that Vanessa claims Brian was helpless against Malou – she would “fling her arms around his neck and her legs around his waist and he would whisper secrets that would have her panting with laughter, and it was all just nauseating.” According to Vanessa, Malou had quickly figured out that she was “the other woman,” and “spent her days trying to ruin her. Vanessa says, “She covered me in poop. She devastated my hair. After every encounter with her, I looked like the forest ape.”
As years passed and Malou turned into “the long, lovely bonobo she would become,” she became even more clever and resourceful – “ready to kick some ass.”
Finally, there was talk of her being released into the wild with six other bonobos. Then, in 2008, she died suddenly. Bonobos are vulnerable to most human diseases, and in Congo, there are a lot of them.
Vanessa claims Brian’s heart was broken. She says, “He still loves bonobos and studies their minds and fights tirelessly for their conservation, but he will never love another bonobo like he loved Malou.”
In 2011, Brian and Vanessa had a little girl. And, of course, they called her “Malou.”
(Vanessa Woods. “A moment that changed me – my husband fell in love with a bonobo.” The Guardian. https://www.theguardian.com/commentisfree/2015/oct/01/my-husband-fell-in-love-bonobo October 01, 2015.)
You can read Vanessa's book, Bonobo Handshake: A Memoir of Love and Adventure in the Congo (June 7, 2011). Think what you will, readers.
To close, they say “love is strange.” I know that's true. After finding research about our human ancestors, I think it's a little stranger than I originally thought.
Love Is Strange
By Mickey and Sylvia
Love
Love is
strange
Lot of people
Take it for a game
Once you get it
You
never want to quit, no no
After you've had it
You're in an
awful fix
Many people
Don't
understand, no no
They think loving
Is money in the hand
Your
sweet loving
Is better than a kiss
When you leave me
Sweet
kisses I miss
Sylvia
Yes,
Mickey
How do you call your lover boy
Come here, lover boy
And
if he doesn't answer
Oh lover boy
And if he still doesn't
answer
I simply say
Baby, oh baby
My sweet baby, you're the
one
Baby, oh baby
My sweet baby, you're the one
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