Tag

Human Evolution

All articles tagged with #human evolution

science3 days ago•5 min saved

Ancient East Asian Hominins Invented Complex Stone Tools During a Harsh Ice Age

New dating of a Lingjing, China rib crystal shows 146,000-year-old stone cores and flakes were made by an archaic human relative (Homo juluensis) during a harsh ice age, revealing planning and advanced stone‑knapping skills. The calcite dating revises theTools’ age from a warmer period to a cold glacial era, suggesting sophisticated technology arose under environmental stress and indicating broader East Asian implications for Paleolithic innovation.

via ScienceAlert|

#homo-juluensis #human-evolution #ice-age

science4 days ago•13 min saved

Legs Before Hands: Evolution's Leg-Driven Route to Right-Handedness

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.

via Space Daily|

#bipedalism #brain-size #handedness

science4 days ago•7 min saved

Two Evolutionary Shifts Underlie Humans' Strong Right-Handedness

Oxford researchers analyzed 2,025 individuals from 41 primate species using Bayesian models and found that a combination of upright walking (bipedalism) and larger brain size likely drove humans’ strong right-hand bias. Early hominins showed modest right-hand preferences, which intensified in Homo species, culminating in near-universal right-handedness in modern humans, while Homo floresiensis may have had a weaker bias; left-handedness persistence remains unexplained, suggesting a two-stage evolution—freeing the hands for tool use via walking upright, then brain expansion strengthening the bias.

via SciTechDaily|

#bipedalism #brain-expansion #handedness

human-history6 days ago•16 min saved

Walking Upright and Brain Growth May Have Shaped Humans' Right-Hand Bias

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.

via Gizmodo|

#bipedalism #brain-size #handedness

science7 days ago•9 min saved

How Upright Walking and Big Brains Made Humans Right-Handed

A new framework argues humans became predominantly right‑handed as our ancestors first stood upright, freeing hands for tools and later developing larger brains; culture then reinforced the bias, with the strongest right‑hand dominance emerging where brain expansion and specialized bipedal bodies aligned. Left‑handedness persists and may offer competitive advantages or be tied to brain development; findings appear in PLOS Biology.

via ZME Science|

#bipedalism #evolution #handedness

culture8 days ago•11 min saved

Two Evolutionary Shifts Pushed Humans Toward a Right-Hand Bias

An Oxford study across 41 primate species finds that humans aren’t evolutionarily exceptional in handedness once brain size and limb proportions are included; a two-stage path links upright walking (freed hands) and later brain expansion to the strong right-hand bias (mean handedness index 0.76), suggesting the 90% right-handed world arose from changes in movement and brain growth rather than a single gene, with culture possibly reinforcing it.

via Interesting Engineering|

#biology #bipedalism #culture

science10 days ago•6 min saved

Ancient Coexistence in Ethiopia: Early Homo and Australopithecus Shared the Landscape 2.6–2.8 Ma

Fossils from Ledi Geraru, Ethiopia, show early Homo and an unnamed Australopithecus species living in the same area about 2.6–2.8 million years ago, supporting a bushy, overlapping view of human evolution. Volcanic ash dating anchors the ages and helps reconstruct the ancient habitat, suggesting multiple hominin lineages coexisted in eastern Africa, with more fossils needed to name the Australopithecus species and clarify their interactions.

via ScienceDaily|

#australopithecus #early-homo #ethiopia

science11 days ago•5 min saved

DNA Methylation Switches Help Explain What Makes Humans Unique

A study comparing human, chimpanzee, and hybrid cells shows that cis-regulatory DNA methylation—driven by changes at CpG sites—primarily drives methylation differences between humans and chimps, with effects rippling to nearby sites. These epigenetic shifts correlate with human-specific traits in cognition, development timing, craniofacial features, and disease susceptibility, suggesting DNA methylation coordinates regulatory changes beyond gene expression to help define what makes us human.

via Indian Defence Review|

#cis-regulatory #cpg-sites #dna-methylation

science12 days ago•182 min saved

Enamel clues link Homo erectus to Denisovans in a web-like human tree

Scientists extracted ancient enamel proteins from six Homo erectus teeth found in three sites in China (about 400,000 years old) using a new, minimally invasive enamel-etching technique. They identified two shared amino acid variants, one of which also appears in Denisovans and some modern humans, suggesting interbreeding between Homo erectus, Denisovans, and Homo sapiens and supporting a networked view of human evolution. The study relied on proteins (not DNA) and analyzed teeth from Hexian and Zhoukoudian, with five males and one female identified, highlighting open questions about how these populations relate to each other.

via CNN|

#ancient-proteins #denisovans #hominin-interbreeding

science12 days ago•5 min saved

Toba Eruption Massive, Humans Survived: Africa Reveals Adaptive Resilience

New archaeological and tephra evidence from Africa shows that the 74,000-year-old Toba eruption, though vastly larger than Mt. St. Helens, did not trigger a uniform human extinction; sites in South Africa and Ethiopia reveal continuous habitation and adaptive behaviors—microlithic tool trends, early bow-and-arrow tech, and sophisticated foraging—dated to the eruption period. These findings revise, but do not fully dismiss, the Toba catastrophe hypothesis and highlight refugia and migration pathways out of Africa via arid periods and dry‑season river corridors known as blue highways.

via Indian Defence Review|

#adaptive-foraging #archaeology #cryptotephra

science13 days ago•7 min saved

Why Humans Sleep Less: An Evolutionary Trade-Off Behind the Sleep Paradox

Anthropologist David R. Samson argues that humans biologically need about 9.5 hours of sleep but typically get under seven, because ancestral shifts from tree to ground sleeping favored short, deep, REM-rich bouts that free time for foraging, social learning and tool use. Drawing on chimpanzee nest-building and fieldwork with the Hadza and BaYaka, the book frames nest-building as a cognitive catalyst in primate evolution, while highlighting sleep’s broad importance to health and cognition and noting some gaps in the comparison to other species.

via Nature|

#anthropology #human-evolution #neuroscience

science16 days ago•4 min saved

Neanderthals Turned Rhino Teeth into Multitools for Stone Work

New research shows Neanderthals in ancient France and Spain recycled rhinoceros molars into multipurpose tools used to shape stone, process hides, and manipulate plant fibers. Wear patterns on 281 fossilized rhino teeth, plus experiments using real rhino teeth, indicate these were functional tools, highlighting Neanderthals’ sophisticated technology and cognitive abilities.

via VICE|

#archaeology #human-evolution #neanderthals

science26 days ago•7 min saved

Ancient Genome Tracks Rapid Turn in Human Evolution

A massive ancient-DNA study analyzing data from more than 10,000 ancient individuals, plus thousands of published and modern genomes, finds that directional natural selection was more active and occurred more recently than previously believed. The analysis identifies 479 gene variants that rose or fell in West Eurasia over the last 10,000 years, with selection intensifying after farming. Although such selection explains only about 2% of genetic changes, many variants tie to traits seen today—like light skin, immune responses, and disease risks—and some gene groups influenced polygenic traits. Caution is urged in linking ancient variants to modern traits, and results are not limited to West Eurasia. The researchers have made data and methods public to extend work to other populations and time periods, with implications for health, disease understanding, and potential gene-therapy considerations.

via SciTechDaily|

#ancient-dna #genomics #human-evolution

science26 days ago•5 min saved

Living Brain Data Upend the Neanderthal-Cognition Narrative

A PNAS study using MRI data from 200 living individuals shows brain differences between Neanderthals and anatomically modern humans fall within the range of variation seen among today’s populations, challenging the notion of cognitive inferiority. The findings suggest Neanderthal disappearance was more likely due to demographic processes and interbreeding, with archaeological and genetic evidence indicating shared traits and capabilities rather than a large cognitive gap.

via Indian Defence Review|

#brain #cognition #genetic-swamping

science28 days ago•7 min saved

Neanderthal brains lie within the modern human size range, study finds

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.

via Ars Technica|

#brain-size #cognition #endocasts