Skulls with Mix of Traits Illuminate Human Evolution

Neandertals’ trademark facial features took shape as a first step in their evolution, while their other defining features came along later, and not all at once, researchers have reported. These researchers were studying a collection of skulls in a Spanish cave, where they identified both Neandertal-derived features in the skulls and features associated with more primitive humans. Having this new data has allowed scientists to better understand hominin evolution during the Middle Pleistocene, a period in which the path of hominin evolution has been controversial. 

The work of Arsuaga et al. helps address hypotheses about Neandertal evolution, specifically the accretion model hypothesis, which suggests that Neandertals evolved their defining features at different times, not in a single linear sweep. 

Read more about this research from the 20 June issue of Science here.

[Image © Javier Trueba / Madrid Scientific Films. Please click here for more information.]

© 2014 American Association for the Advancement of Science. All Rights Reserved.

Skulls with Mix of Traits Illuminate Human Evolution

Neandertals’ trademark facial features took shape as a first step in their evolution, while their other defining features came along later, and not all at once, researchers have reported. These researchers were studying a collection of skulls in a Spanish cave, where they identified both Neandertal-derived features in the skulls and features associated with more primitive humans. Having this new data has allowed scientists to better understand hominin evolution during the Middle Pleistocene, a period in which the path of hominin evolution has been controversial.

The work of Arsuaga et al. helps address hypotheses about Neandertal evolution, specifically the accretion model hypothesis, which suggests that Neandertals evolved their defining features at different times, not in a single linear sweep.

Read more about this research from the 20 June issue of Science here.

[Image © Javier Trueba / Madrid Scientific Films. Please click here for more information.]

© 2014 American Association for the Advancement of Science. All Rights Reserved.

Early Homo Skull Suggests a Single Species

Cover of the 18 October issue of Science: Photo of a 1.77-million-year-old complete adult skull (braincase volume: 546 cubic centimeters) of early Homo from the site of Dmanisi, Georgia. Together with the fossilized bones of four additional individuals discovered in close proximity, the skull indicates that populations of early Homo comprised a wider range of morphological variation than traditionally assumed, which implies a single evolving lineage with continuity across continents. See pages 297 and 326.

[Photo: © Guram Bumbiashvili/Georgian National Museum]

Anyone wishing to use the cover of Science must contact AAAS to request permission to do so.

© 2013 American Association for the Advancement of Science. All Rights Reserved.

Foraging Band Societies Weren’t War-like, Study Suggests

Although some have argued that violent conflict often appears to be a component of “human nature,” new evidence suggests that early humans killed each other over primarily personal issues — and that war, or the pitting of one group against another, is a more recent development. These new findings contradict some previous studies that have painted mobile forager band societies (frequently treated as models of early human behavior) in a particularly violent light.

Read more about this research from the 19 July issue of Science here.

[Image courtesy of Douglas Fry. Click the image for more information.]

© 2013 American Association for the Advancement of Science. All Rights Reserved.

No Single Origin for Agriculture in the Fertile Crescent

A rich assemblage of fossils and artifacts in the foothills of the Zagros Mountains in Iran has revealed that the early inhabitants of the region began cultivating cereal grains for agriculture between 12,000 and 9,800 years ago. The discovery implies that the transition from foraging to farming took place at roughly the same time across the entire Fertile Crescent, not in a single core area of the “cradle of civilization,” as previously thought.

Read more about this research from the 5 July issue of Science here.

[Image courtesy of TISARP/University of Tübingen. Click the image for more information.]

© 2013 American Association for the Advancement of Science. All Rights Reserved.

古代マヤ文明には複数の集団との文化交流があった

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マヤ文明の起源に関してはこれまでに、2つの優勢な説があった。1つは現在のメキシコ南部、グアテマラ、ベリーズにあたる地域でほぼ独自に発展したという説。もう1つはマヤ文明より古いオルメカ文明の文化的影響を大きく受けたという説である。今回、ともにアリゾナ大学(米国、ツーソン)の研究者であるTakeshi Inomata(猪俣健)、Daniela Triadan夫妻が率いる米国や日本の研究者から成る発掘調査チームは、これらの2説ではマヤ文明の起源を十分に説明できないことを明らかにした。セイバルの広場群やピラミッド群と、グアテマラの古代マヤ遺跡はおそらく、紀元前約1,000年~700年に南部メソアメリカで起こっていた広範な文化的交流から生じたと彼らは提唱している。

Science 4月26日号に掲載)

[Reconstruction: Daniela Triadan; Photo: Takeshi Inomata. Click for caption information.]

Anyone wishing to use the cover of Science must contact AAAS to request permission to do so.

© 2013 American Association for the Advancement of Science. All Rights Reserved.

Ancient Maya Swapped Culture With Multiple Groups

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Until now, two theories have dominated the debate concerning the origin of the Maya civilization: one suggesting that the Maya developed almost entirely on their own in what is now southern Mexico, Guatemala, and Belize, and another suggesting that the older Olmec civilization was the Maya’s dominant cultural influence. Takeshi Inomata and Daniela Triadan, a husband-and-wife team from the University of Arizona in Tucson, along with colleagues from the U.S. and Japan, however, found that neither of these theories could tell the full story of the Maya. According to the researchers, the plazas and pyramids at Ceibal, an ancient Maya site in Guatemala, probably arose from broad cultural exchanges that took place across southern Mesoamerica from about 1,000 to 700 BCE.

This research appeared in the 26 April issue of Science.

[Reconstruction: Daniela Triadan; Photo: Takeshi Inomata. Click for caption information.]

Anyone wishing to use the cover of Science must contact AAAS to request permission to do so.

© 2013 American Association for the Advancement of Science. All Rights Reserved.

Human Evolution Takes a Twist With Australopithecus sediba

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A set of six research reports, accompanied by an introductory essay in the 12 April issue of Science serve up a complete view of the anatomy and likely habits of Australopithecus sediba, the 2-million-year-old fossil remains of several partial skeletons found in 2008 at the site of Malapa, near Johannesburg, South Africa. The studies show that Au. sediba is a mosaic of human and ape-like traits, with a human-like pelvis, hands and teeth, and a chimpanzee-like foot. Researchers still aren’t sure where Au. sediba fits into the hominin family tree, but these six studies show that the Malapa fossils are a striking example of human evolution.

Read more here and here.

[Reconstruction by Peter Schmid, Photo by Lee R. Berger. Image courtesy of Lee R. Berger and the University of the Witwatersrand. Click the image for more information.]

© 2013 American Association for the Advancement of Science. All Rights Reserved.

Older Origins for Spear-Making Technology

Early humans were lashing stone tips to wooden handles to make spears and knives about 200,000 years earlier than previously thought, new research suggests. “Hafting” was an important technological advance that made it possible to handle or throw sharp points with much more power and control. Both Neandertals and early Homo sapiens made hafted spear tips, and evidence of this technology is relatively common after about 200,000 to 300,000 years ago. Jayne Wilkins and colleagues now present multiple lines of evidence implying that stone points from the site of Kathu Pan 1 in South Africa were hafted to form spears around 500,000 years ago.

Read more about this research from the 16 November issue of Science here.

[Image courtesy of Jayne Wilkins; click the image for more information.]

© 2012 American Association for the Advancement of Science. All Rights Reserved.

Bipedal Human Ancestor Spent Time in the Trees

After analyzing the fossilized shoulder bones of a juvenile Australopithecus afarensis called Selam, or DIK-1-1, researchers in Science suggest that these early human ancestors, although bipedal, were also very active climbers. This slideshow from the AAAS Office of Public Programs highlights these new findings from the report by David Green and Zeresenay Alemseged titled, “Australopithecus afarensis Scapular Ontogeny and Function, and the Role of Climbing in Human Evolution.”

Click the image to watch a slideshow of images about the research. Read more about this research from the 26 October issue of Science here.

© 2012 American Association for the Advancement of Science. All Rights Reserved.

How Local Institutions Tamed Warfare in Papua New Guinea

It’s been argued recently that humans have become less violent as modern-day cultural institutions and governments have evolved. But, at least some small-scale societies have their own customary institutions that can quell runaway warfare, as a new study of the Enga of Papua New Guinea shows. Whereas many studies of violence rely heavily on models, Polly Wiessner at the University of Utah and Nitze Pupu at Enga Take Anda in Papua New Guinea gathered data from precolonial warfare, 501 recent wars and 129 customary court sessions to analyze an unusual natural experiment.

Read more about this research from the 28 September issue of Science here.

[Click the image for more information. Image courtesy of Polly Wiessner]

© 2012 American Association for the Advancement of Science. All Rights Reserved.

© 2014 American Association for the Advancement of Science. All Rights Reserved.