オックスフォード大学の研究チームは、直立歩行と脳の大型化が、現代のヒトに見られる強い右利き傾向の主な要因である可能性が高いことを突き止めた。この調査結果は、霊長類および絶滅したヒト族の分析に基づいている。
トーマス・A・ピュシェル博士率いる研究チームは、41種におよぶ2,025頭のサルや類人猿のデータを調査した。研究ではベイズ統計モデリングを用いて、脳の大きさや、二足歩行の指標となる腕と脚の長さの比率といった要因を検証した。これらの形質を考慮に入れた結果、ヒトは霊長類の中で進化上の例外的な存在ではなくなった。
AIによるレポート AIによって生成された画像 事実確認済み
MRI scans of 120 adults in the United States found that people with higher psychopathic traits had a striatum—an area involved in reward and motivation—that was about 10% larger on average than those with few or no such traits, according to a study in the Journal of Psychiatric Research.
A recent study indicates that left-handed individuals may have an edge in competitive situations, while right-handed people are better at cooperation. This finding challenges evolutionary expectations about handedness. Researchers explore why around 10 percent of humans remain left-handed despite potential survival disadvantages.
AIによるレポート
Researchers have uncovered a 7.2-million-year-old femur in Bulgaria that shows features suggesting bipedal walking, predating known African hominin fossils. The find, linked to the ape species Graecopithecus freybergi, challenges the idea that upright walking evolved solely in Africa. However, experts caution that more evidence is needed to confirm bipedality.
Three rhesus macaque monkeys equipped with brain-computer interfaces navigated virtual environments using only their thoughts. Researchers implanted around 300 electrodes in motor and premotor cortex areas to enable this control. The experiments aim to improve intuitive control for people with paralysis.
AIによるレポート
A newly described crocodile relative from the Late Triassic period began life walking on four legs before adopting a bipedal stance in adulthood, scientists say. The poodle-sized Sonselasuchus cedrus, unearthed in Arizona, reveals unusual growth patterns in ancient reptiles. Researchers detailed the findings in a study published this year.
Scientists have found genetic evidence that modern humans reached New Guinea and Australia around 60,000 years ago, backing the long chronology over more recent estimates. The international team, led by researchers at the University of Huddersfield and the University of Southampton, analyzed nearly 2,500 mitochondrial DNA genomes from Aboriginal Australians, New Guineans, and Southeast Asian populations. Their work suggests early migrants used at least two routes through Southeast Asia.
AIによるレポート
A newly discovered fossil ape from northern Egypt, named Masripithecus moghraensis, dates to 17-18 million years ago and may be closely related to the ancestors of modern apes. Researchers argue this finding shifts the focus from East Africa to northern Africa for early ape evolution. The species provides key insights into hominoid diversity during a period of continental connections.