All articles tagged with #brain size
A new PLOS Biology study analyzing 2,025 primates across 41 species argues that humans’ near-90% right-handedness arises from the combined effects of rapid brain growth and a long leg-to-arm ratio from sustained bipedalism: with legs freed from locomotion, the hands could specialize in manipulation, and the larger brain provided the cognitive substrate, making humans the extreme outlier among primates.
Oxford researchers analyzed data from 2,025 individuals across 41 primate species and found that the near-universal human right-handedness likely stems from two defining human traits—upright walking and larger brains—with limb-length balance helping predict hand preference; other factors like tool use, diet, or habitat did not fully explain the pattern.
A Oxford-led study analyzing 2,025 primates suggests humans' extreme right-handedness arose from two key evolutionary milestones—upright walking and brain expansion—that shifted early hominins from mild to strong right-hand bias, with Homo species showing increasing dominance and Homo floresiensis exhibiting weaker bias; the findings support a two-stage process and raise questions about why left-handedness persists and how culture reinforces right-handedness.
A new comparison of Neanderthal endocasts with MRI scans from 400 modern humans shows Neanderthal brain size and regional variation fall within the range of modern human variation. Brain size differences don’t reliably predict cognition, and the findings—alongside evidence of complex tool use, symbolic thought, and social organization—suggest Neanderthals were cognitively on par with early Homo sapiens, challenging the idea that they were outmatched by size or intelligence.
New research suggests that the small size of Homo floresiensis, or Hobbits, resulted from slowed growth during childhood rather than in utero development, challenging previous assumptions that brain size increase was the primary driver of human evolution. The study highlights how tooth and brain size relationships can provide insights into fossil species, and emphasizes that small body size on islands is an adaptive response, not a reflection of lower intelligence.
Research shows that longer thumbs in primates are linked to larger brains, especially the neocortex, indicating that manual dexterity and brain evolution developed together, with implications for understanding human cognitive and motor development.
A study analyzing 94 primate species found that longer thumbs are associated with larger brains, particularly the neocortex, suggesting that manual dexterity may have driven brain growth in humans and other primates, with implications for understanding the evolution of intelligence and tool use.
The study finds a significant correlation between relative thumb length and brain size across 95 primate species, supporting the idea that neural and bodily adaptations coevolved to enhance manual dexterity, with implications for understanding human evolution and tool use.
Research indicates that in primates, longer thumbs are associated with larger brains, suggesting co-evolution of manual dexterity and brain development, with implications for understanding human evolution and tool use.
Scientists found that long-lived mammals tend to have expanded gene families related to immune surveillance and cellular maintenance, which support tissue stability and brain health, suggesting that resilience systems rather than metabolism changes are key to longevity.
A new study published in PNAS reveals that the evolution of larger brains in modern humans, Neanderthals, and their relatives occurred gradually over millions of years, rather than through sudden leaps between species. Researchers from the University of Reading, Oxford, and Durham used a comprehensive fossil dataset and advanced methods to demonstrate steady brain size growth driven by gradual adaptation within species. This challenges previous theories of dramatic evolutionary changes and highlights the complexity of brain evolution.
A new study reveals that human brain size increased gradually within species over millions of years, rather than through sudden leaps between species. This challenges previous beliefs about brain evolution, suggesting that gradual changes, rather than dramatic events, drove the development of larger brains in humans and their relatives. The research, involving a comprehensive dataset of ancient human fossils, highlights the complexity of evolutionary pressures on brain size, showing that larger brains evolved primarily from within-species changes.
A study using data from the Framingham Heart Study reveals that human brains have been increasing in size over recent decades, with those born in the 1970s having larger brain volumes and surface areas compared to those born in the 1930s. This increase in brain size may potentially lower the risk of age-related dementias, suggesting the possibility of enhanced brain reserve. However, the study's cohort mainly consisted of non-Hispanic White, healthy, and well-educated individuals, so caution is advised in generalizing the findings to the broader U.S. population.
A new study from the University of California analyzing data from the Framingham Heart Study suggests that human brains have been increasing in size between the 1930s and 1970s, potentially reducing dementia risk. The research found significant increases in various cerebral measures over time, with larger brain structures possibly reflecting improved brain development and health. While genetics play a major role in brain size, external influences such as health, social, cultural, and educational factors may also contribute. However, brain size is just one piece of the puzzle, and further research is needed to understand the impact on dementia risk, particularly in more diverse cohorts.
A new study from the University of California Davis has found that the human brain has increased in size by 6.6 percent between the 1930s and the 1970s, with noticeable growth in volume, surface areas, and structures such as the hippocampus. This increase is attributed to improved health, social-cultural changes, and educational factors, and could potentially explain the decreasing incidence of brain diseases like Alzheimer’s. The research suggests that external influences, in addition to genetics, play a role in determining brain size and long-term brain health.