Most of us harbor about 2 percent Neanderthal DNA, inherited when our ancestors bred with Neanderthals more than 50,000 years ago. This was revealed back in 2010, when geneticists salvaged enough fragments of ancient DNA from Neanderthal bones to piece together a full genome. The discovery squelched a longstanding debate over whether Neanderthals and modern humans met — they did — and mated — oh yeah.
But why do we only have 2 percent Neanderthal ancestry? And what are the effects of that Neanderthal DNA on living humans? And why did our ancestors survive and Neanderthals go extinct? We’ve attributed our supremacy to bigger brains, better diets and advanced technology, but there may be a subtler, less flattering explanation for our evolutionary success. Read More
Stone tools, like Acheulean hand axes, remain well-preserved for eons because they are stones first, tools second. Fired ceramics remain well-preserved for millennia because they are, in essence, human-made stone. Metal tools may, in some rare instances, endure for millennia, but their material hardness belies chemical fragility; most are not stable over the long term. Bone tools, like their metal counterparts, may remain well-preserved, but preservation is highly specific to local burial chemistry. Artifacts made of perishable plant and animal remains, such as clothing, shoes, nets, baskets, and many toys, are rarely well-preserved, and therefore not very well-understood. Read More
I have always wondered why our species Homo sapiens, that evolved in Africa about 200,000 years ago, seemed to do nothing special for the first 150,000 years. Because it is not until about 50,000 years ago that the first sign of creative thinking emerged with beautiful cave paintings found in Spain, France and Indonesia.
Around the same time a new sub-species referred to as anatomically modern humans or Homo sapiens sapiens appears. Anatomically modern humans were more slender than their earlier ancestors; they had less hair, smaller skulls. They looked basically like us.
But these changes weren’t just cosmetic. Two recent papers throw some light on how the revolutionary development of smaller and more fine-boned humans influenced the growth of cooperative culture, the birth of agriculture and human dominance of the planet.
Depending on who you talk to, Kennewick Man is either among the most important archaeological finds in North American history, or the desecrated body of a distant forebear known as “The Ancient One.”
Kennewick Man’s remains have fueled a nearly two-decade-long showdown between science and cultural rights, and now those tensions are at the forefront once again. On Thursday, archaeologists who sequenced Kennewick Man’s genome announced that he is more closely related to modern Native Americans than any other population on the planet.
The finding, scientifically speaking, appears to settle a fierce, decades-old debate among researchers regarding the man’s lineage.
But for the Pacific Northwest tribes demanding a proper burial for Kennewick Man, the results corroborate what they already knew from their oral traditions, and may renew their call for repatriation.
Mark Changizi is an evolutionary neurobiologist and director of human cognition at 2AI Labs. He is the author of The Brain from 25000 Feet, The Vision Revolution, and his newest book, Harnessed: How Language and Music Mimicked Nature and Transformed Ape to Man.”
Earlier this week there was a debate on the origins of music at the Atlantic between two well-known psychologists. Geoffrey Miller (author of The Mating Mind) thinks music is an instinct, one due to sexual selection. On the other side is Gary Marcus (author of Guitar Zero), who believes music is a cultural invention. Given my recent book on the issue, Harnessed, many have asked me where I fall on the question, Is music an instinct or an invention?
My answer is that music is neither instinct nor invention—or, from another perspective, music is both—and this debate provides an opportunity to remind ourselves that there is a third option for the origins of music, an option that I have argued may also underlie our writing and language capabilities.
What if music only has the illusion of instinct? Might there be processes that could lead to music that is exquisitely shaped for our brains, even though music wasn’t something we ever evolved by natural seletion to process? Music in this case wouldn’t be merely an invention, one of the countless things we do that we’re not “supposed” to be doing and that we’re not particularly good at—like logic or rock-climbing. Instead, music would fit our brain like a glove, tightly inter-weaved amongst our instincts…but yet not be an instinct itself.
There is such a process that can give the gleamy shine of instinct to capabilities we never evolved to possess. It’s cultural evolution.
Once humans were sufficiently smart and social that cultural evolution could pick up steam, a new blind watchmaker was let loose on the world, one that could muster designs worthy of natural selection, and in a fraction of the time. Cultural selection could shape our artifacts to co-opt our innate capabilities.
Cultural evolution is an old idea, but there has been a resurgence of interest in it thanks to researchers like Stanislas Dehaene and Laurent Cohen, who have studied how writing neuronally recycles parts of our visual object-recognition hardware (see Reading in the Brain). And in my research I have tried to get down to brass tacks on how culture manages to harness our brain hardware.