Neandertals modified white-tailed eagle claws 130,000 years ago

Discovery sheds new light on cognitive abilities of human predecessors

 AN IMAGE OF WHITE-TAILED EAGLE TALONS FROM THE KRAPINA NEANDERTAL SITE IN PRESENT-DAY CROATIA, DATING TO APPROXIMATELY 130,000 YEARS AGO, MAY BE PART OF A JEWELRY ASSEMBLAGE.
CREDIT: LUKA MJEDA, ZAGREB
Krapina Neandertals may have manipulated white-tailed eagle talons to make jewelry 130,000 years ago, before the appearance of modern human in Europe, according to a study published March 11, 2015 in the open-access journal PLOS ONE by David Frayer from University of Kansas and colleagues from Croatia.

Researchers describe eight mostly complete white-tailed eagle talons from the Krapina Neandertal site in present-day Croatia, dating to approximately 130,000 years ago. These white-tailed eagle bones, discovered more than 100 years ago, all derive from a single time period at Krapina. Four talons bear multiple edge-smoothed cut marks, and eight show polishing facets or abrasion. Three of the largest talons have small notches at roughly the same place along the plantar surface.

The authors suggest these features may be part of a jewelry assemblage, like mounting the talons in a necklace or bracelet. Some have argued that Neandertals lacked symbolic ability or copied this behavior from modern humans, but the presence of the talons indicates that the Krapina Neandertals may have acquired eagle talons for some kind of symbolic purpose. They also demonstrate that the Krapina Neandertals may have made jewelry 80,000 years before the appearance of modern humans in Europe.

"It's really a stunning discovery. It's one of those things that just appeared out of the blue. It's so unexpected and it's so startling because there's just nothing like it until very recent times to find this kind of jewelry," David Frayer said.

Epoch-defining study pinpoints when humans came to dominate planet Earth

The human-dominated geological epoch known as the Anthropocene probably began around the year 1610, with an unusual drop in atmospheric carbon dioxide and the irreversible exchange of species between the New and Old Worlds, according to new research published today in Nature.

Previous epochs began and ended due to factors including meteorite strikes, sustained volcanic eruptions and the shifting of the continents. Human actions are now changing the planet, but are we really a geological force of nature driving Earth into a new epoch that will last millions of years?

Scientists at UCL have concluded that humans have become a geological power and suggest that human actions have produced a new geological epoch.

Defining an epoch requires two main criteria to be met. Long-lasting changes to the Earth must be documented. Scientists must also pinpoint and date a global environmental change that has been captured in natural material, such as rocks, ancient ice or sediment from the ocean floor. Such a marker - like the chemical signature left by the meteorite strike that wiped out the dinosaurs - is called a golden spike.

The study authors systematically compared the major environmental impacts of human activity over the past 50,000 years against these two formal requirements. Just two dates met the criteria: 1610, when the collision of the New and Old Worlds a century earlier was first felt globally; and 1964, associated with the fallout from nuclear weapons tests. The researchers conclude that 1610 is the stronger candidate.

The scientists say the 1492 arrival of Europeans in the Americas, and subsequent global trade, moved species to new continents and oceans, resulting in a global re-ordering of life on Earth. This rapid, repeated, cross-ocean exchange of species is without precedent in Earth's history.

They argue that the joining of the two hemispheres is an unambiguous event after which the impacts of human activity became global and set Earth on a new trajectory. The first fossil pollen of maize, a Latin American species, appears in marine sediment in Europe in 1600, becoming common over subsequent centuries. This irreversible exchange of species satisfies the first criteria for dating an epoch - long-term changes to Earth.

The researchers also found a golden spike that can be dated to the same time: a pronounced dip in atmospheric carbon dioxide centred on 1610 and captured in Antarctic ice-core records (1). The drop occurred as a direct result of the arrival of Europeans in the Americas. Colonisation of the New World led to the deaths of about 50 million indigenous people, most within a few decades of the 16th century due to smallpox. The abrupt near-cessation of farming across the continent and the subsequent re-growth of Latin American forests and other vegetation removed enough carbon dioxide from the atmosphere to produce a drop in CO2. Thus, the second requirement of a golden spike marker is met.

The researchers have named the 1610 dip in carbon dioxide the 'Orbis Spike'. They chose the Latin word for 'world' because this golden spike was caused by once-disconnected peoples becoming globally linked.

Lead author, Dr Simon Lewis (UCL Geography and University of Leeds), said: "In a hundred thousand years scientists will look at the environmental record and know something remarkable happened in the second half of the second millennium. They will be in no doubt that these global changes to Earth were caused by their own species. Today we can say when those changes began and why. The Anthropocene probably began when species jumped continents, starting when the Old World met the New. We humans are now a geological power in our own right - as Earth-changing as a meteorite strike."

He added: "Historically, the collision of the Old and New Worlds marks the beginning of the modern world. Many historians regard agricultural imports into Europe from the vast new lands of the Americas, alongside the availability of coal, as the two essential precursors of the Industrial Revolution, which in turn unleashed further waves of global environmental changes. Geologically, this boundary also marks Earth's last globally synchronous cool moment before the onset of the long-term global warmth of the Anthropocene."

The authors also considered the merits of dating the Anthropocene to 1964, which saw a peak in radioactive fallout following nuclear weapons testing. This marker is seen in many geological deposits, and by the 1960s human impact on the Earth was large. However, the researchers note that while nuclear war could dramatically alter Earth, so far it has not. While the fallout from nuclear bomb tests is a very good marker, the testing of nuclear weapons has not been - in geological terms - an Earth-changing event.

The beginning of the Industrial Revolution, in the late 18th century, has most commonly been suggested as the start of the Anthropocene. This linked a clear turning point in human history, and the rise of atmospheric carbon dioxide from fossil fuel use is a long-term global environmental change of critical importance. However, the researchers did not find a golden spike at that time because most effects were local, while the global exponential rise in carbon dioxide was too smooth an increase to form a precisely dated marker (2).

The authors' new paper ends by highlighting some implications of formally defining the Anthropocene.

Co-author, geologist Professor Mark Maslin (UCL Geography) said: "A more wide-spread recognition that human actions are driving far-reaching changes to the life-supporting infrastructure of Earth will have implications for our philosophical, social, economic and political views of our environment. But we should not despair, because the power that humans wield is unlike any other force of nature, it is reflexive and therefore can be used, withdrawn or modified. The first stage of solving our damaging relationship with our environment is recognising it."

An official decision on whether to formally recognise the Anthropocene, including when it began, will be initiated by a recommendation of the Anthropocene Working Group of the Subcommission of Quaternary Stratigraphy, due in 2016 (3).

Millions of modern men found to be descendants of 11 Asian dynastic leaders

• University of Leicester researchers discover that many modern men have genetic links to ancient figures such as Genghis Khan
• Study suggests that millions of modern Asian men are descended from 11 ancient leaders, including Genghis Khan
• Sample examined the Y chromosomes of 5,000 Asian men from 127 populations

Historical nomadic and mobile populations allowed for Y chromosomes to be spread far and wide
Geneticists from the University of Leicester have discovered that millions of modern Asian men are descended from 11 powerful dynastic leaders who lived up to 4,000 years ago - including Mongolian warlord Genghis Khan.

The study, which is funded by the Wellcome Trust and published in the journal European Journal of Human Genetics, examined the male-specific Y chromosome, which is passed from father to son, in more than 5,000 Asian men belonging to 127 populations.

Most Y-chromosome types are very rare, but the team discovered 11 types that were relatively common across the sample and studied their distributions and histories.

Two common male lineages have been discovered before, and have been ascribed to one well-known historical figure, Genghis Khan, and another less-known one, Giocangga. The Leicester team found genetic links via a chain of male ancestors to both Genghis Khan and Giocangga, in addition to nine other dynastic leaders who originated from throughout Asia and date back to between 2100 BC and 700 AD.

The project's leader, Professor Mark Jobling from the University of Leicester's Department of Genetics, said: "The youngest lineages, originating in the last 1700 years, are found in pastoral nomadic populations, who were highly mobile horse-riders and could spread their Y chromosomes far and wide. For these lineages to become so common, their powerful founders needed to have many sons by many women, and to pass their status - as well as their Y chromosomes - on to them. The sons, in turn, could then have many sons, too. It's a kind of trans-generation amplification effect."

First author of the study, Patricia Balaresque (now at Université Paul Sabatier in Toulouse), added: "Identifying the ancestors responsible for these lineages will be difficult or impossible, as it would rely on finding their remains and extracting and analysing ancient DNA. This hasn't yet been done for Genghis Khan, for example, so the evidence remains circumstantial, if pretty convincing."

Precise dating of ancient charcoal found near skull in Manot Cave , Israel

A partial human skull unearthed in 2008 in northern Israel may hold some clues as to when and where humans and Neanderthals might have interbred. The key to addressing this, as well as other important issues, is precisely determining the age of the skull. A combination of dating methods, one of them performed by Dr. Elisabetta Boaretto, head of the Weizmann Institute's D-REAMS (DANGOOR Research Accelerator Mass Spectrometry) laboratory, has made it possible to define the period of time that the cave was occupied and thus the skull's age. The combined dating provides evidence that Homo sapiens and Homo neanderthalensis could have lived side by side in the area.

The Manot Cave, a natural limestone formation, had been sealed for some 15,000 years. It was discovered by a bulldozer clearing the land for development, and the first to find the partial skull, which was sitting on a ledge, were spelunkers exploring the newly-opened cave. Five excavation seasons uncovered a rich deposit, with stone tools and stratified occupation levels covering a period of time from at least 55,000 to 27,000 years ago.

Dating the skull presented a number of difficulties. "Because it was already removed from the layer where it was presumably deposited," says Dr. Elisabetta Boaretto, "we had to look for clues to tell us where and when it belonged in the setting of the archaeological record in the cave."

The age of the skull was first determined to be 54.7 thousand years old by a technique known as the uranium-thorium method, which was applied to the thin mineral deposit on the skull. But the estimated possible error in that type of method is plus or minus 5.5 thousand years. To obtain independent confirmation of the date, a different type of dating was required, e.g., radiocarbon dating.

To narrow down the possible range of the skull's age and determine when the skull's owner had lived in the cave, the archaeological team led by Prof. Israel Hershkovitz of Tel Aviv University, Dr. Ofer Marder of Ben Gurion University and Dr. Omry Barzilai of the Israel Antiquities Authority turned to Dr. Boaretto. She and her team participated in the excavation of the cave and applied radiocarbon dating to carefully selected charcoal remains, so that the whole cave, and thus the timing of human occupation, was mapped. 

The agreement between the two methods -- carbon and uranium-thorium -- provided the necessary support for the "correction" in the original uranium-thorium dating of the skull, which then helped fix the true age of the skull at around 55,000 years.

The date and shape of the Manot Cave skull provides some intriguing evidence that humans and Neanderthals might have interbred sometime during the human trek out of Africa, most likely as the former passed through the Middle East before spreading out north and east. The 55,000-year-old partial skull is the first evidence of a human residing in the region at the same time as Neanderthals, whose remains have been found at several nearby sites. Archaeologists are now searching for more evidence of ancient human habitation in the cave. 

If, indeed, the mixing between humans and Neanderthals took place in this area, it would suggest that the owner of the skull and his kin may have been the ancestors of all modern non-Africans.

Evidence for the human genus -- Homo --now goes back 2.8 million years

A fossil lower jaw found in the Ledi-Geraru research area, Afar Regional State, Ethiopia, pushes back evidence for the human genus -- Homo -- to 2.8 million years ago, according to a pair of reports published March 4 in the online version of the journal Science. The jaw predates the previously known fossils of the Homo lineage by approximately 400,000 years. It was discovered in 2013 by an international team led by Arizona State University scientists Kaye E. Reed, Christopher J. Campisano and J Ramón Arrowsmith, and Brian A. Villmoare of the University of Nevada, Las Vegas.

For decades, scientists have been searching for African fossils documenting the earliest phases of the Homo lineage, but specimens recovered from the critical time interval between 3 and 2.5 million years ago have been frustratingly few and often poorly preserved. As a result, there has been little agreement on the time of origin of the lineage that ultimately gave rise to modern humans. At 2.8 million years, the new Ledi-Geraru fossil provides clues to changes in the jaw and teeth in Homo only 200,000 years after the last known occurrence of Australopithecus afarensis ("Lucy") from the nearby Ethiopian site of Hadar.

Found by team member and ASU graduate student Chalachew Seyoum, the Ledi-Geraru fossil preserves the left side of the lower jaw, or mandible, along with five teeth. The fossil analysis, led by Villmoare and William H. Kimbel, director of ASU's Institute of Human Origins, revealed advanced features, for example, slim molars, symmetrical premolars and an evenly proportioned jaw, that distinguish early species on the Homo lineage, such as Homo habilis at 2 million years ago, from the more apelike early Australopithecus. But the primitive, sloping chin links the Ledi-Geraru jaw to a Lucy-like ancestor.

"In spite of a lot of searching, fossils on the Homo lineage older than 2 million years ago are very rare," says Villmoare. "To have a glimpse of the very earliest phase of our lineage's evolution is particularly exciting."

In a report in the journal Nature, Fred Spoor and colleagues present a new reconstruction of the deformed mandible belonging to the 1.8 million-year-old iconic type-specimen of Homo habilis ("Handy Man") from Olduvai Gorge, Tanzania. The reconstruction presents an unexpectedly primitive portrait of the H. habilis jaw and makes a good link back to the Ledi fossil.

"The Ledi jaw helps narrow the evolutionary gap between Australopithecus and early Homo," says Kimbel. "It's an excellent case of a transitional fossil in a critical time period in human evolution."

Global climate change that led to increased African aridity after about 2.8 million years ago is often hypothesized to have stimulated species appearances and extinctions, including the origin of Homo. In the companion paper on the geological and environmental contexts of the Ledi-Geraru jaw, Erin N. DiMaggio, of Pennsylvania State University, and colleagues found the fossil mammal assemblage contemporary with this jaw to be dominated by species that lived in more open habitats--grasslands and low shrubs--than those common at older Australopithecus-bearing sites, such as Hadar, where Lucy's species is found.

"We can see the 2.8 million year aridity signal in the Ledi-Geraru faunal community," says research team co-leader Kaye Reed, "but it's still too soon to say that this means climate change is responsible for the origin of Homo. We need a larger sample of hominin fossils, and that's why we continue to come to the Ledi-Geraru area to search."

Did humans migrate from Africa all-at-once or in phases based on weather?

Map showing location of the study site and extent of bajada system in southeast Arabia, including other identified sections of the Al Ain fan (UAE—United Arab Emirates).

Credit: Parton et al.

Considerable debate surrounds the migration of human populations out of Africa. Two predominant hypotheses concerning the timing contrast in their emphasis on the role of the Arabian interior and its changing climate. In one scenario, human populations expanded rapidly from Africa to southern Asia via the coastlines of Arabia approx. 50,000 to 60,000 years ago. Another model suggests that dispersal into the Arabian interior began much earlier (approx. 75,000 to 130,000 years ago) during multiple phases, when increased rainfall provided sufficient freshwater to support expanding populations.

Ash Parton and colleagues fall into the second camp, writing, "The dispersal of early human populations out of Africa is dynamically linked with the changing climate and environmental conditions of Arabia. 

Although now arid, at times the vast Arabian deserts were transformed into landscapes littered with freshwater lakes and active river systems. 

 Such episodes of dramatically increased rainfall were the result of the intensification and northward displacement of the Indian Ocean Monsoon, which caused rainfall to reach across much of the Arabian Peninsula."

Parton and colleagues present a unique alluvial fan aggradation record from southeast Arabia spanning the past approx. 160,000 years. Situated along the proposed southern dispersal route, the Al Sibetah alluvial fan sequence provides a unique and sensitive record of landscape change in southeast Arabia. This record is to date the most comprehensive terrestrial archive from the Arabian Peninsula, and provides evidence for multiple humid episodes during both glacial and interglacial periods.

Evidence from the Al Sibetah alluvial fan sequence indicates that during insolation maxima, increased monsoon rainfall led to the widespread activation of drainage systems and grassland development throughout regions that were important for the dispersal of early human populations.

Previously, the timing of episodes of increased humidity was largely linked to global interglacials, with the climate of Arabia during the intervening glacial periods believed to be too arid to support human populations. Parton and colleagues suggest, however, that periods of increased rainfall were not driven by mid-high latitude deglaciations every ~100,000 years, but by periods of maximum incoming solar radiation every ~23,000 years.

They write, "The occurrence of humid periods previously identified in lacustrine or speleothem records highlights the complexity and heterogeneity of the Arabian paleoclimate, and suggests that interior migration pathways through the Arabian Peninsula may have been viable approximately every 23,000 years since at least marine isotope state (MIS) 6," about 191 thousand years ago.

Neanderthal groups based part of the their lifestyle on the sexual division of labor

Neanderthal communities divided some of their tasks according to their sex. This is one of the main conclusions reached by a study performed by the Spanish National Research Council (CSIC), published in the Journal of Human Evolution. This study, which analyzed 99 incisors and canine teeth of 19 individuals from three different sites (El Sidron, in Asturias - Spain, L'Hortus in France, and Spy in Belgium), reveals that the dental grooves present in the female fossils follow the same pattern, which is different to that found in male individuals.

Analyses show that all Neanderthal individuals, regardless of age, had dental grooves. According to Antonio Rosas, CSIC researcher at the Spanish National Museum of Natural Sciences: "This is due to the custom of these societies to use the mouth as a third hand, as in some current populations, for tasks such as preparing the furs or chopping meat, for instance".

Rosas specifies that "what we have now discovered is that the grooves detected in the teeth of adult women are longer than those found in adult men. Therefore we assume that the tasks performed were different".

Other variables analyzed are the tiny spalls of the teeth enamel. Male individuals show a greater number of nicks in the enamel and dentin of the upper parts, while in female individuals these imperfections appear in the lower parts.

It is still unclear which activities corresponded to women and which ones to men. However, the authors of the study note that, as in modern hunter-gatherer societies, women may have been responsible for the preparation of furs and the elaboration of garments. Researchers state that the retouching of the edges of stone tools seems to have been a male task.

Almudena Estalrrich, CSIC researcher at the Spanish National Museum of Natural Sciences, adds: "Nevertheless, we believe that the specialization of labor by sex of the individuals was probably limited to a few tasks, as it is possible that both men and women participated equally in the hunting of big animals".

Rosas concludes: "The study of Neanderthals has provided numerous discoveries in recent years. We have moved from thinking of them as little evolved beings, to know that they took care of the sick persons, buried their deceased, ate seafood, and even had different physical features than expected: there were redhead individuals, and with light skin and eyes. So far, we thought that the sexual division of labor was typical of sapiens societies, but apparently that's not true".