We Finally Know When and How Our Modern Brains Evolved
We know that our large, globe-shaped human brains evolved from earlier Homo species, and that their shape plays a crucial role in Homo sapiens ability to think cognitively.
Scientists have long wondered just when and how our ancestors' brains evolved into the current globular shape that enables you to read and comprehending this story, though. Now a new study, published earlier this week in the Science Advances journal, finally has some answers.
The basis of this study involved looking at fossils of Homo sapiens across different time periods. The study first found that brain size in early homo sapiens already fell within the range of present-day humans 300,000 years ago. Brain shape, though, evolved much more gradually with our lineage, reaching the variations found in present day humans between about 100,000 and 35,000 years ago.
"This process started only after other key features of craniofacial morphology appeared modern and paralleled the emergence of behavioral modernity as seen from the archeological record," the study says.
The most significant finding of the study, however, may be that the changes in brain shape perfectly align with the point in history when humans developed the ability to build tools, think critically, and practice self-awareness. "Our findings are consistent with important genetic changes affecting early brain development within the H. sapiens lineage since the origin of the species and before the transition to the Later Stone Age and the Upper Paleolithic that mark full behavioral modernity," the study says.
In other brainy news, scientists have pinpointed a chemical that can delete bad memories, a la the Charlie Kaufman cult-classic Eternal Sunshine of the Spotless Mind. Known as gamma-aminobutyric acid, or GABA, the chemical is used to send messages between different nerve cells in the brain, while dulling your memory of painful events at the same time.
Early details are also starting to leak out about Elon Musk's secretive Neuralink project, which will allows the human brain to directly interface with hardware and software (instead of relying on other hardware and software). Musk also hopes that this tech gives us a fighting chance against the rapidly advancing AI."Until people see robots going down the street killing people," Musk famously said, "they don't know how to react."
This emerging tech has caused some in the scientific community to sound off about the potential life-saving benefits—and threats to humanity—that comes with the widespread implementation of such advanced neural technology.