The genes of monkeys, modern humans, and Neanderthals were compared.
According to a new analysis, creativity may have been one of the critical reasons Homo sapiens survived and prevailed over similar animals, including Neanderthals and chimps.
According to recent research, humans could spread out and conquer the world due to a new DNA alteration (or mutation) that appeared in their DNA about 85,000 years ago. Humans did not develop an insatiable desire for new experiences as a result of this DNA transition. Instead, it allowed them to get away with only eating plants to promote proper brain growth.
This was sufficient to let humanity loose on the planet. After this tiny error first occurred in our three billion DNA letters, nothing has been the same.
According to senior author Dr. Claude Robert Cloninger, a professor emeritus in the psychology and genetics departments at Washington University in St. Louis, the notion that imagination may have offered Homo sapiens a survival advantage over Neanderthals has been around for a long time. Still, he added, proving that is difficult because we don’t know how inventive Neanderthals were.
Cloninger explained, “The trouble with testing imagination in endangered animals is, of course, you can’t speak to them.” As a result, a multinational team of researchers led by the University of Granada in Spain and the Washington University School of Medicine in St. Louis looked at genes to see what differentiated humans from their distant ancestors, including their creative potential.
The researchers had previously discovered 972 modern genes in Homo sapiens that control three different learning and memory systems: emotional reactivity, self-control, and self-awareness. The ability to create relational bonds and learn habits is part of the dynamic reactivity network. In contrast, the ability to set expectations, collaborate with others and make tools are part of the self-control network.
According to the research, the self-awareness network includes “episodic learning,” or recalling and building on previous activities, as well as autobiographical memory of an individual’s life as a story of history, present, and future “through which the participant can seek alternate viewpoints with intuitive intuition and imaginative creativity.”
Cloninger explained that self-awareness is “what allows one to have divergent, initial artistic thought [and] to be very resilient.”
The researchers studied DNA from Neanderthal (Homo neanderthalensis) bones, contemporary humans (Homo sapiens), and chimps in the current analysis (Pan troglodytes). They discovered that Homo sapiens, Neanderthals, and chimps all had the same genes for the oldest network — emotional reactivity. However, chimps lacked the genes that humans use to develop self-awareness and self-control.
“The Neanderthals were almost halfway between the chimps and modern humans in terms of the number of these genes they bore,” Cloninger told Live Science, “in terms of the number of these genes they carried.”
Furthermore, 267 of the 972 genes were unique to Homo sapiens, and they were all regulatory genes. To put it another way, they regulate the behavior of other genes. These genes, which aren’t found in chimps or Neanderthals, control the neural networks that hold self-awareness and imagination.
Homo sapiens is the only species with this feature.
The emotional reactivity network originated about 40 million years ago in primates and apes, the self-control network about 2 million years ago, and the self-awareness and imagination network about 100,000 years ago, when humans were under threat from a shifting environment that limited the availability of food and other resources needed for survival, Cloninger said.
According to the report, about 40,000 years ago, Homo sapiens with “unprecedented cultural and technical complexity” started gradually replacing Neanderthals all over the world. According to the authors, our Homo sapiens ancestors’ ingenuity and self-awareness undoubtedly drove this maturity, allowing them to live longer, healthier lives.
Children and teenagers would have had more time to study and gain skills if they had lived longer. Living longer, healthier lives would have enabled teamwork among individuals and extended families to help their children, grandchildren, and other community members succeed. As a result, “the technical inventiveness, behavioral resilience, and exploratory temperament required to enable Homo sapiens to spread across the world more effectively than other human lineages” would be possible, according to the authors.
However, the research has many drawbacks, including the fact that dynamic characteristics like imagination and self-awareness are challenging to determine solely based on genes and that Neanderthals are no longer around, making it difficult to evaluate them exclusively based on their genes. (A person’s climate, for example, may have an impact on their personality and behavior.) Indeed, some scientists are skeptical that matching the current human genome to that of a long-extinct population will yield reliable results.
“Even though the authors established networks of genes that are correlated with certain measurements of self-awareness, imagination, or prosocial behavior, we don’t know the causal relation between genetics and these higher traits,” Thomas Suddendorf, a geneticist, professor in the School of Psychology at the University of Queensland in Australia who was not part of the study, said.
While the results are intriguing, Suddendorf cautioned Live Science in an email that “I would warn against drawing any firm conclusions from such data regarding extant, let alone extinct, animals.” According to him, humans are “unquestionably” more imaginative than all living creatures, including chimps.
“We cannot rule out the likelihood that Neanderthals had genes that were not present in [Homo] sapiens and affected their personalities and learning ability,” the study’s authors wrote. To put it another way, Neanderthals may not have shared our genes for imagination and self-awareness but still had their own collection of genes that we don’t understand.
The results were announced in the journal Molecular Psychiatry on April 21.
Out from the Water, Mutating
Human brains are similar to modern electronics in that they require rare materials to function correctly. While an iPhone requires various rare Earth minerals, human brains need a large amount of fatty acid known as long-chain polyunsaturated fatty acids or LC-PUFAs.
Humans cannot produce these fatty acids on their own and must instead obtain them from their diet (sort of like vitamin C). Unfortunately for our forefathers, humans aren’t so effective at converting the fatty acids found in plants into the ones they need. And, despite our prowess at obtaining them from wildlife, we didn’t begin hunting in earnest until about 50,000 years ago.
According to a group of researchers, the response could be found in a mutation that allowed ancient humans to properly use plant fatty acids to produce the LC-PUFAs they needed for their brains. Humans will now get enough nutrients by eating vegetables, allowing them to migrate and conquer the earth.
The fact that Africans have a specific DNA gap that Asians and Europeans do not support this theory. This distinction reinforces an enzyme (FADS1) that transforms plant fatty acids into the ones humans use for brain function. To put it another way, Africans have a mutation that helps them get some of their brain fatty acids from plants.
When the researchers examined the DNA surrounding this enzyme in Africans, they discovered more minor variations than expected. This is a telltale indication that the mutation spread rapidly through the population (geneticists call a “selective sweep”). As a result, after a few people figured out how to use plants successfully, they were off and running, rapidly populating the globe.
These scientists estimated that the mutation first occurred about 85,000 years ago based on a close examination of the DNA (which fits the story nicely). Unfortunately, these studies are not very reliable, and a wide variety of dates based about 85,000 years ago are possible. According to the article, it was 85,000 years ago +/- 84,000 years ago.
The researchers also believe that this DNA disparity comes at a price. The fact that the mutation is less frequent in Asians and Europeans leads them to this conclusion. Humans no longer wanted to rely on plants until they could search for land animals, according to the theory, so the mutation was lost.
Of note, it’s also possible that the humans who migrated to Europe and Asia did not have this DNA gap any longer. Humans did not leave Africa until 40,000 years ago, even after they had begun hunting and could obtain their fatty acids from the animals they consumed. It would be difficult to determine whether Europeans and Asians lost their DNA differences or never had them in the first place.
Scientists will discover more about human genetic origins as they sequence more humans (and their long-lost relatives). They’ll figure out why people moved the way they did, who they bred with before eradicating them, and a lot more. They can eventually be able to explain what it is about our DNA that makes us human.