The Neanderthals had intelligence. However, what precisely set their brains apart from those of our own ancestors?
Specialists say that the brains of Homo neanderthalensis and Homo sapiens were similar. But slight differences in the structure and development of the two species' brains could've changed the ways they thought about the world. (Credit: life_in_a_pixel/Shutterstock)
According to tradition, Homo sapiens and Homo neanderthalensis had different levels of intelligence. However, anthropologists and archaeologists are adamant that the gap between the two species is closing.
In actuality, evidence from their prehistoric behaviors indicates more and more that the two species used comparable survival techniques. They produced similar noises and used comparable tools because they lived in similar communities. In addition, the most current research reveals that the two produced artwork that was comparable to one another, demonstrating their mutual preference for abstraction.
What about their brains, though? Was there anything in their physical makeup that set their thinking apart?
Yes, according to some experts. Experts in the fields of paleontology, paleoneurology, and paleogenetics believe that even minor variations in the structure and growth of the two species' brains may have caused their cognition to diverge in significant and complicated ways.
Beginning of the Neanderthals in Brutality
Around two centuries ago, when the first Neanderthal fossils were discovered, researchers had no idea what they were dealing with. Some people believed they had discovered their own distant ancestors, while others believed the specimens represented something altogether different.
They were confident in only one conclusion at the time: Regardless of the technical categorization of the fossils, they believed that the creature they discovered was not intelligent when it roamed the earth thousands of years ago.
Neanderthal Mentality
An examination of a collection of 1860s specimens claims that "darkness characterized the being to which the fossil belonged." The thoughts and passions that originally resided there "never rose above those of a brute."
This now-outdated belief, which was first expressed around the time the Neanderthals gained recognition as a distinct species, was based on the Neanderthals' "singularly different" skull structure from that of our own species.
This distinction quickly led to the labeling of the Neanderthals as a brutish race, imprisoned in "benightedness" until our own intellectually superior species overcame them 40,000 years ago.
Intelligence of the Neanderthals
Since then, archaeologists and anthropologists have discovered a ton of evidence suggesting that Neanderthal behavior was on par with that of our own species. In addition to sharing our predecessors' survival techniques and equipment, current study indicates that the Neanderthals also communicated and developed art and ornamentation civilizations.
These intricate activities imply that the Neanderthals' minds were similar to our own in complexity. But what precisely do we know about their brains' architecture and growth?
Did Neanderthals Possess Greater Intellect?
Since these tissues are often the first to degrade after death, specialists are still looking for the first pieces of Neanderthal brain. However, they have discovered numerous fossilized skulls belonging to the species that have the castings or inside surfaces of the brains they originally held.
Size of Neanderthal Brain
Overall, these skulls suggest that H. neanderthalensis and H. sapiens brains were around the same size, with H. neanderthalensis brains narrowly outperforming H. sapiens brains in terms of total volume.
Size of Neanderthal Cranium
Although measurements aren't always accurate and shift over time, experts estimate that the average Neanderthal skull held about 1500 cubic centimeters (or 51 ounces) of cerebral tissue, compared to only 1350 cubic centimeters (or 46 ounces) for their more modern counterparts.
A Brain in Strain
Neanderthal brains and braincases were large, but they were also slightly stretched, resulting in an odd, semi-spherical cranium with a large bulge at the back. This bulge, known as the "occipital bun," was one of the first aspects of Neanderthal anatomy that researchers found and characterized.
The Neanderthal Brain's Organization
Paleontologists and paleoneurologists hypothesize that the peculiar characteristics of Neanderthals also had an impact on the size, shape, and organization of the various structures within their brains, changing their specific thought processes.
For instance, according to some research, the cerebellum of H. neanderthalensis was thought to be smaller than that of H. sapiens due to the anatomy of the Neanderthal skull. According to these research, a species' ability to learn, think logically, comprehend language, and engage socially can all be significantly impacted, which would have a negative effect on its ability to survive.
This is supplemented by a variety of related theories regarding the idiosyncrasies of the Neanderthal mind. For instance, some paleontologists and paleoneurologists claim that the species' larger, bulkier bodies, which were harder to move than our own, meant that a greater portion of the species' brain was focused on coordinating basic body motions.
The Neanderthal Brain's Evolution
Beyond its straightforward structure, experts are discovering a great deal about the Neanderthal brain's growth from infancy to adulthood.
For instance, the size and shape of juvenile, adolescent, and adult skulls indicate that the mental development of H. neanderthalensis occurred far more slowly than that of modern humans. At age 8, they were less than 90% of their typical adult volume. And although it may not sound slow, experts claim that, in terms of total volume, that is roughly the same age at which H. sapiens brains mature today.
Building Neanderthal Brains
Genetic studies provide more evidence that the Neanderthal brain developed differently from ours. In fact, despite the fact that experts have traditionally focused on skulls in their efforts to understand Neanderthal intelligence, the recent reconstruction of the Neanderthal genome is encouraging some to look instead to the ancient genes that regulate brain growth as a way to distinguish between H. neanderthalensis and H. sapiens thinking.
NOVA1
For instance, a group of geneticists studied the NOVA1 gene in 2021, which controls how the brain develops in both Homo sapiens and Homo neanderthalensis. The researchers observed that when they introduced two different forms of the gene into collections of uncultured cells, the form of NOVA1 found in H. neanderthalensis produced bumpier blobs of brain tissue whereas the type of NOVA1 found in H. sapiens produced smooth, spherical aggregates.
TKTL1
A second team of geneticists adopted a similar strategy with the gene TKTL1, which stimulates the formation of neurons, the year after, in 2022. The H. sapiens type of TKTL1 promoted significantly more neurons than the H. neanderthalensis form did.
These results do show a difference in brain development between H. neanderthalensis and H. sapiens, however they do not fully explain this difference. The influence of NOVA1 and TKTL1 on something as complex as cognition can only be truly understood in the context of a more complete genome, experts claim, as individual genes are simply small threads in a larger genetic tapestry.
Though it will take some time, experts predict that future research in this area will clarify the impact of a number of other genes on the development of the Neanderthal brain. This investigation will ultimately help paint a clearer picture of the distinctions between our cognition and those of our closest relatives when combined with the knowledge gained from the anatomy of skulls.
