The Story of Us: Did Neandertal evolve all at once? Or slowly over time?

Credit: Image © Javier Trueba / Madrid Scientific Films

Skull 17 from the Sima de los Huesos site in Sierra de Atapuerca, Spain.

Trying to keep up with the latest research in the middle of the Scientific Revolution is a task beyond my capabilities, though it is fun trying.
Take, for instance, one of our predecessor species, Neandertal.  Type the name into a science search site, and over a dozen breakthrough studies were published just over the last several years.  These studies deal with the ancient but help explain how we got be the thinking animal we are.

One question of debate in some circles is: do species evolve all at once?  Or slowly over time?

For a writer, all at once is a bonanza of potential conflict and crises.  Slowly over time, less so, but still rife with those with a new feature such as a dominant brow ridge being ostracized - a theme in Jean Aul's delightful series, Earth's Children.

Here is a story of a study that compares and contrasts skulls with a mix of Neandertal and more primitive traits that help illuminate human evolution.


Researchers studying a collection of skulls in a Spanish cave identified both Neandertal-derived features and features associated with more primitive humans in these bones. This "mosaic pattern" supports a theory of Neandertal evolution that suggests Neandertals developed their defining features separately, and at different times -- not all at once. Having this new data from the Sima de los Huesos site, as the Spanish cave is called, has allowed scientists to better understand hominin evolution during the Middle Pleistocene, a period in which the path of hominin evolution has been controversial.

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Period of maximum glaciation during the Pleistocene.
Note that southern Europe is clear of ice. 

The Pleistocene Epoch is typically defined as the time period that began about 1.8 million years ago and lasted until about 11,700 years ago. The most recent Ice Age occurred then, as glaciers covered huge parts of the planet Earth.

There have been at least five documented major ice ages during the 4.6 billion years since the Earth was formed — and most likely many more before humans came on the scene about 2.3 million years ago.

The Pleistocene Epoch is the first in which Homo sapiens evolved, and by the end of the epoch humans could be found in nearly every part of the planet.

Source: livescience.com

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"The Middle Pleistocene was a long period of about half a million years during which hominin evolution didn't proceed through a slow process of change with just one kind of hominin quietly evolving towards the classic Neandertal," said lead author Juan-Luis Arsuaga, Professor of Paleontology at the Complutense University of Madrid.

"With the skulls we found," co-author Ignacio Martínez, Professor of Paleontology at the University of Alcalá, added, "it was possible to characterize the cranial morphology of a human population of the European Middle Pleistocene for the first time."

About 400 to 500 thousand years ago, in the heart of the Pleistocene, archaic humans split off from other groups of that period living in Africa and East Asia, ultimately settling in Eurasia, where they evolved characteristics that would come to define the Neandertal lineage. Several hundred thousand years after that, modern humans -- who had evolved in Africa -- settled in Eurasia, too. They interbred with Neandertals, but even then showed signs of reproductive incompatibility. Because of this, modern humans eventually replaced Neandertals.

The degree of divergence between Neandertals and modern humans over such a short period of time has surprised scientists. Why did Neandertals differentiate so quickly from other early hominins? What pattern of changes did Neandertals undergo?

To answer these questions, scientists have needed an accurate picture of European populations around 400,000 years ago, the early stages of the Neandertal lineage. This has been challenging, however, because the European fossil record -- an important tool for answering these questions -- is isolated and dispersed, consisting of remains from disparate timelines. Samples at the Sima de los Huesos site in Atapuerca, Spain, however, are different.

"What makes the Sima de los Huesos site unique," Arsuaga said, "is the extraordinary and unprecedented accumulation of hominin fossils there; nothing quite so big has ever been discovered for any extinct hominin species -- including Neanderthals."

"This site has been excavated continuously since 1984," Martínez added. "After thirty years, we have recovered nearly 7,000 human fossils corresponding to all skeletal regions of at least 28 individuals. This extraordinary collection includes 17 fragmentary skulls, many of which are very complete."

The 17 skulls belong to a single population of a fossil hominin species. Some of have been studied before, but seven are presented anew here, and six are more complete than ever before. With these intact samples at their fingertips, the researchers made progress characterizing defining features.
Their work has helped 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.

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"For decades the nature of the evolutionary process that gave rise to Neanderthals has been discussed," explained Martínez. "An important question in these debates was whether the 'neandertalization process' involved all regions of the skull from the beginning, or if, on the contrary, there were various stages in this process that affected different parts of the skull at different times."

The researchers' skull samples showed Neandertal features present in the face and teeth, but not elsewhere; the nearby braincase, for example, still showed features associated with more primitive hominins.

"We think based on the morphology that the Sima people were part of the Neanderthal clade," Arsuaga said, "although not necessarily direct ancestors to the classic Neanderthals." They were part of an early European lineage that includes Neanderthals, but is more primitive than the later Pleistocene variety.

Critically, many of the Neandertal-derived features the researchers observed were related to mastication, or chewing. "It seems these modifications had to do with an intensive use of the frontal teeth," Arsuaga said. "The incisors show a great wear as if they had been used as a 'third hand," typical of Neanderthals."

The work of Arsuaga et al. suggests that facial modification was the first step in Neandertal evolution. This mosaic pattern fits the prediction of the accretion model.

"One thing that surprised me about the skulls we analyzed," Arsuaga said, "is how similar the different individuals were. The other fossils of the same geological period are different and don´t fit in the Sima pattern. This means that there was a lot of diversity among different populations in the Middle Pleistocene."

Indeed, other European Middle Pleistocene Homo sapiens do not exhibit the suite of Neandertal-derived features seen in this fossil group. Thus, more than one evolutionary lineage appears to have coexisted during the European Middle Pleistocene, with that represented by the Sima sample being closer to the Neandertals.

Arsuaga and his team were delighted to work on this effort. "Finding a single tooth is a great success in any other site of comparable age, so imagine what it is like to painstakingly reconstruct 17 skulls," he said. "It's like finding a treasure."

So 17 skulls at one site, skulls with a variety of features, but showing a tendency to use the teeth as "a third hand."  What was going on there - socially and culturally?  Were food sources changing?  Was competition from other hominid groups increasing?  Well, speculate away as speculation is the mother of interesting fiction.

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Story Source:  Materials provided by American Association for the Advancement of Science. J. L. Arsuaga, I. Martínez, L. J. Arnold, A. Aranburu, A. Gracia-Téllez, W. D. Sharp, R. M. Quam, C. Falguères, A. Pantoja-Pérez, J. Bischoff, E. Poza-Rey, J. M. Parés, J. M. Carretero, M. Demuro, C. Lorenzo, N. Sala, M. Martinón-Torres, N. García, A. Alcázar de Velasco, G. Cuenca-Bescós, A. Gómez-Olivencia, D. Moreno, A. Pablos, C.-C. Shen, L. Rodríguez, A. I. Ortega, R. García, A. Bonmatí, J. M. Bermúdez de Castro, and E. Carbonell. Neandertal roots: Cranial and chronological evidence from Sima de los Huesos. Science, 2014

The next generation of Invisibility Cloaks: "You can't touch this."

canadianawareness.org

A prototype invisibility cloak for use by soldiers in combat.  Someday.

Frodo's ring and Harry Potter's cloak gave them invisibility, actually an old fantasy realized by science over the past few years. Today, objects really can be hidden from light, heat or sound. However, hiding of an object from being touched still remained to be accomplished. 

Now scientists from the Karlsruhe (Germany) Institute of Technology (KIT) have succeeded in creating a method that "hides" an object from a person's sense of touch, sort of making the pea under the mattress not noticeable to the princess.

The "touch" invisibility" device developed by KIT prevents  a person's sense of touch responding to the object.  Here's an explanation from the press release of how the KIT technology works:

The invisibility cloak is based on a so-called metamaterial that consists of a polymer. Its major properties are determined by the special structure. "We build the structure around the object to be hidden. In this structure, strength depends on the location in a defined way," explains Tiemo Bückmann, KIT, the first author of the article. "The precision of the components combined with the size of the complete arrangement was one of the big obstacles to the development of the mechanical invisibility cloak." The metamaterial is a crystalline material structured with sub-micrometer accuracy. It consists of needle-shaped cones, whose tips meet. The size of the contact points is calculated precisely to reach the mechanical properties desired. In this way, a structure results, through which a finger or a measurement instrument cannot feel its way.

In the invisibility cloak produced, a hard cylinder is inserted into the bottom layer. Any objects to be hidden can be put into its cavity. If a light foam or many layers of cotton would be placed above the hard cylinder, the cylinder would be more difficult to touch, but could still be felt as a form. The metamaterial structure directs the forces of the touching finger such that the cylinder is hidden completely. "It is like in Hans-Christian Andersen's fairy tale about the princess and the pea. The princess feels the pea in spite of the mattresses. When using our new material, however, one mattress would be sufficient for the princess to sleep well," Bückmann explains.

Implementation of such a mechanical invisibility cloak is rather complex. After the definition of the desired mechanical properties, the physical basic equations are inverted mathematically in order to draw conclusions with respect to the structure of the metamaterial. Using this method, materials not encountered in nature can be planned. Examples are solids which are stiff to pressure, but soft to shear. For manufacture from the polymer, the direct laser writing method of the KIT spinoff Nanoscribe is applied. It reaches the required precision over the complete sample length of several millimeters.

The mechanical invisibility cloak represents pure physical fundamental research, but might open up the door to interesting applications in a few years from now, as it allows for producing materials with freely selectable mechanical properties. Examples are very thin, light, and still comfortable camping mattresses or carpets hiding cables and pipelines below.

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How you or any writer uses this technology in combination with other invisibility techniques is up to your imagination.  I do seem to remember a scene in Tom Clancy's The Cardinal of the Kremlin in which a woman is submerged in a sensory deprivation tank resulting in her complete mental collapse.  With these type of devices would it be possible to do much the same without the expense of a special tank?  Simply disoriented a character in your story by suppressing their five (or six) senses?

This would be an interesting thought experiment indeed.

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Story Source: Materials provided by Karlsruhe Institute of Technology. T. Bückmann, M. Thiel, M. Kadic, R. Schittny, M. Wegener. An elasto-mechanical unfeelability cloak made of pentamode metamaterials. Nature Communications, 2014

What Bronze Age Brits used for jewelry

A Stone Age burial dating from 5000-7000 BC shows
the skeletons of two women who were buried wearing
necklaces made of numerous shells.

A new study by scientists at the University of York has shed new light on the use of mollusk shells as personal adornments by Bronze Age people.

The research team used amino acid racemisation analysis (a technique used previously mainly for dating artifacts), light microscopy, scanning electron microscopy and Raman spectroscopy, to identify the raw materials used to make beads in a complex necklace discovered at an Early Bronze Age burial site at Great Cornard in Suffolk, UK.

They discovered that Bronze Age craftspeople used species like dog whelk and tusk shells, both of which were likely to have been sourced and worked locally, to fashion tiny disc-shaped beads in the necklace.

About Tusk Shells
Tusk shells (left) or Scaphopoda, meaning literally "boat-footed" are a class of shelled marine mollusks. Shells range from about 0.5 to 15 cm in length. These mollusks live on soft substrates offshore (usually not intertidally). Because of this subtidal habitat and the small size of most species, many beachcombers are unfamiliar with them; their shells are usually not nearly as common or as easily visible in the beach drift as the shells of sea snails and clams.

The shells of scaphopods are conical and curved and they are usually whitish in color. Because of these characteristics, the shell somewhat resembles a miniature elephant's tusk, hence the common name tusk shell. However, unlike an elephant's tusk, the shells of these molluscs are hollow and open at both ends.

About the Dog Whelk

The dog whelk, dogwhelk, or Atlantic dogwinkle, scientific name Nucella lapillus, is a species of predatory sea snail, a carnivorous marine gastropod mollusc in the family Muricidae, the rock snails.

This species is found around the coasts of Europe and in the northern west Atlantic coast of North America. It is also can be found in estuarine waters along the Atlantic coasts. This species prefers rocky shores, where it eats mussels and acorn barnacles

The researchers included archaeologists, mathematicians, chemists and physicists, the latter from the BioArCh and York Centre for Complex Systems Analysis (YCCSA) and the Departments of Archaeology, Mathematics, Chemistry and Physics at the University of York. Dr Sonia O'Connor, of the University of Bradford's Department of Archaeological Sciences, carried out the light and electron microscopy, and prehistoric jewellery specialist Dr Alison Sheridan, of National Museums Scotland, facilitated access to the Great Cornard necklace, which had been excavated by Suffolk Archaeology.

When it was first established that the tiny white beads had been made from shell, the question arose as to its source. Had the shell been obtained locally or did it originate from a species from further afield, perhaps even the Mediterranean thorny oyster (Spondylus)? The Mediterranean thorny oyster is a shell of long-standing symbolic and cultural significance which is known to have been used on the Continent around the time when the Great Cornard necklace was made.

But this collaborative research, led by Dr Beatrice Demarchi, of York's Department of Archaeology and BioArCh, and Dr Julie Wilson, of the Departments of Chemistry and Mathematics and YCCSA, has shown this not to be the case, and has suggested an alternative possibility.

Dr Demarchi said: "Dog whelks and tusk shells were likely to be available locally so these people did not have to travel far to get hold of the raw materials for their beads.

"There is evidence, from elsewhere in Britain and further afield, for the use of tusk shells at various times in the past. This may well be because they are relatively easy to work and their hollow shape is very distinctive."

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Story Source:  Materials provided by University of York. Beatrice Demarchi, Sonia O'Connor, Andre de Lima Ponzoni, Raquel de Almeida Rocha Ponzoni, Alison Sheridan, Kirsty Penkman, Y. Hancock, Julie Wilson. An Integrated Approach to the Taxonomic Identification of Prehistoric Shell Ornaments. PLoS ONE, 2014.

Where's Indiana Jones when we need him? Ancient coins looted from archaeological sites

Credit: Nathan Elkins photo

Ancient Constantinian coins.

There is a story here, or at least part of a story, considering that the market in coins and other stolen artifacts is in the billions of dollars annually.  I can picture our hero, Iowa Schwartz, combating an international cartel of dealers in stolen artifacts.  That's been done?  Not the way you would write it.

Here's the article:

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Millions of ancient looted coins from archaeological excavations enter the black market yearly, and a Baylor University researcher who has seen plundered sites likens the thefts to stealing "smoking guns" from crime scenes. But those who collect and study coins have been far too reluctant to condemn the unregulated trade, he says.

"Archaeologists are detectives. When something has been taken away from a historical site, the object is divorced from its relationship with other objects, and its utility for the writing of history -- much like solving a criminal case -- is diminished," said Nathan Elkins, Ph.D., assistant art professor in Baylor's College of Arts & Sciences.

Elkins is the staff numismatist at the excavations of an ancient synagogue from the Roman/Byzantine period in Huqoq, Israel. He has written an article, "Investigating the Crime Scene: Looting and Ancient Coins," that appears in the current issue of Biblical Archaeology Review.

Numismatists -- those who study or collect such currency as coins, tokens, paper money and even such trade objects as shells or lambskins -- must not condone or, worse, encourage that destructive behavior, Elkins said.

Coins are among objects stolen and sold through the multi-billion-dollar black market in antiquities. The New York Times recently reported looting in Spain and also in Egypt, where looters have taken advantage of political upheaval to steal thousands of objects from unprotected sites and even a national museum. The U.S. market alone imports "hundreds of thousands of earth-encrusted coins annually that are smuggled from Balkan nations such as Bulgaria," Elkins says.

He saw up close and personal the results of thefts at a site he previously worked -- a Roman Empire-era fort in Israel.

"One season we arrived and found one area that had been looted by someone with a metal director. Pits were dug into the floors and walls, and the soil dug out was greenish, indicating they had removed copper coins and perhaps other metal objects," he said. "It caused a lot of damage to the site and destroyed information."

Coins taken in such illegal and secretive excavations and touted with fake histories are easy to find in auction catalogs and online storefronts -- and inexpensive to boot, he said. "'Common' coins such as these may sell for the price of a fast-food lunch, but they're invaluable sources to archaeologists and historians," he said. When discovered beneath floors, foundations or wells, they provide information about how people lived and behaved in the past and can date occupation levels and monuments.

Elkins noted that there is "a widespread demand for biblical coins on account of their associations with Judaism, Christianity and the Bible, which of course exacerbates the looting problem. And the intellectual and material consequences of looting biblical coins are equally severe as that of Roman imperial coins and Greek coins."

Among such biblical coins are those used to pay temple taxes, tribute coins to Romans rulers and the "widow's mite," a small coin of little value mentioned in the Gospel of Mark.

For some coin collectors, obtaining coins of questionable origin is a matter of short-sightedness, he said. The origin and history of a coin may be irrelevant to them if their interest is merely in its image, rarity and method of production.

Some scholars and collectors may be hesitant to question a coin's background for fear of alienating dealers or other collectors, Elkins said. And, to be fair, some coins are in public or private collections with no recorded history rather than having been illegally obtained and passed off with a fake history, he said.

Elkins said that most collectors have "a genuine passion" for ancient history, but they must be more assertive and conscientious in reporting suspected illegal activity, insisting on the provenance of coins and avoiding giving money to those who buy from looters and smugglers.

Elkins became fascinated with ancient coins as a teen who was interested in Roman history. "Those (coin) images tended to be politicized, commemorating an imperial virtue or referring to a recent military victory, for example," he said. "As much of the ancient population was illiterate, and the majority of people lived outside of Rome, coins were a primary vehicle for the communication of political ideology in the Roman Empire.

"The study of coins lies at the intersection of multiple fields, including archeology, art history, Classics, ancient history and economics," Elkins said. "Coins are the 'smoking guns,' the definitive evidence -- and it's important to preserve as much evidence as possible."

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Story Source: Materials provided by Baylor University. Nathan T. Elkins. Investigating the Crime Scene: Looting and Ancient Coins. Biblical Archaeology Review, 2014

The demise of English pubs. What will detectives do?

Source:  The LA Times

The man who ran this neighborhood pub, the Wyndham
Arms in Kentisbeare, decided to call it quits. Hit by hard
times, he locked up one evening and never came back,
closing the village's "local" after more than 200 years.

From the days of Sherlock Holmes, Lord Peter and Miss Marple, the stereotypical English public house or pub has been at the core of any fictional detective's work.  And now, sad to say, the English pub is disappearing.

Take a walk through a typical town center or village in England and the chances are you will stumble across a King's Head, Rose & Crown or a Red Lion for a pint of ale or a bite to eat. Pubs are among the most common and well-loved buildings in the country, but have recently been identified as 'a severely threatened building type' by English Heritage.

Academics from the University of Leicester are now looking into pubs in Leeds as part of a research project funded by English Heritage.

Having been the hub of the social life of many communities for centuries, the pub has played a key role in shaping English national identity. However, pubs have been closing in large numbers each week over recent years and are disappearing from our city centers and their outlying areas, often being demolished or converted into housing, shops or restaurants.

A team from the University of Leicester will focus on 19th and 20th century pubs in Leeds with an aim to identify and highlight significant and threatened buildings and increase understanding and appreciation of urban and suburban pubs.

The in-depth area study will involve assessing the buildings themselves and also talking to pub users, owners and local residents about the buildings and their histories.

Emma Dwyer, Business Development Executive for Heritage at the University of Leicester, said: "This is a great opportunity to combine expertise from our School of Archaeology and Ancient History and our Department of History of Art & Film in a project that will have an impact on public understanding of how the pubs of Leeds have developed, and the risks they face from conversion and redevelopment."

Emily Cole from the assessment team at English Heritage said: "Across the country, the number of pubs has been falling steadily for over a century and those dating from 1918-85 are, in particular, increasingly threatened with closure or demolition. They are therefore a high priority for English Heritage.  This project in Leeds is one of a number we are carrying out to increase our knowledge of the architectural style and development of these pubs and their historical and social significance, and to gauge the level of protection that already exists or that it is felt that they deserve."

The results of the project will be presented at a public workshop in Leeds in autumn 2014 and the findings will be written up as a report, forming part of English Heritage's work on historic towns and suburbs for the National Heritage Protection Plan.

It is hoped that this will also prove of use and interest to local authorities, community organisations and other local groups in understanding and protecting these culturally important buildings.

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Story Source:  Materials provided by University of Leicester. "New project to investigate vanishing pubs in England." ScienceDaily.

TECHNOLOGY: Eliminating credit card fraud with palm readers

Credit: Image courtesy of Lund University

Paying for a coffee or lunch by simply scanning your 

palm still sounds like science fiction to most of us.

This post applies to a wide range of genres from SciFi to crime to Romance as well as to our daily lives.  If you've ever had your debit or credit card info stolen and used to run up bills, you know the frustration of getting those charges off your account.  Here's a new application of old technology that may make our accounts more secure.

Paying for a coffee or lunch by simply scanning your palm still sounds like science fiction to most of us. However, an engineering student at Lund University in Sweden has made it happen -- making his the first known company in the world to install the vein scanning technique in stores and coffee shops.

Fredrik Leifland got the idea for his start-up two years ago when he was standing in line at the supermarket. Growing impatient, he knew there had to be an easier and quicker way than using credit cards, and together with a group of classmates at Lund University he soon discovered biometric solutions. While vein scanning technology already existed, there was no system for actually using it as a form of payment.

"We had to connect all the players ourselves, which was quite complex: the vein scanning terminals, the banks, the stores and the customers. The next step was finding ways of packaging it into a solution that was user friendly," says Fredrik.

Their solution worked. There are currently 15 stores and restaurants mainly around the Lund University campus that use the terminals, with 1,600 active users.
Security is a major advantage of the technique, according to Fredrik.

"Every individual's vein pattern is completely unique, so there really is no way of committing fraud with this system. You always need your hand scanned for a payment to go through," he clarifies.

With ongoing plans to expand the business further, and other companies around the world implementing the technology, the payment method seems to be here to stay -- and if Fredrik gets his way -- we'll all spend less time waiting in line at the supermarket in the future.

To see a demonstration, click here:

Qwixter palm scanner in action

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Story Source: Materials provided by Lund University. "Buy lunch, pay with your hand: Vein scanning technique." ScienceDaily.

CRIME: Is letting felons cop pleas to lesser charges working? Research says no.

Photo:  www.ibm.com

Letting a person charged with a felony is a staple of crime fiction as well as in court is a fact of life in the American legal system.  Is it a strategy that saves taxpayers money while lowering crime rates?  Or is it merely an expedient money saver that leads to more violent crime later?

A UC Davis study comparing violent misdemeanor convictions with their original criminal charges has found that subsequent violent crimes could be prevented if criminal charges were reduced less often during plea bargaining.

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The small, preliminary study, posted online June 9 in the American Journal of Preventive Medicine, re-analyzed data on 787 individuals under age 35 who had violent misdemeanor convictions and purchased handguns in California in 1989 or 1990. The goal was to assess the impact of reduced criminal charges on gun purchases and subsequent crime.

"Federal law prohibits felons from legally purchasing firearms, but individuals with violent misdemeanor convictions face no such restrictions in most of the country," said Garen Wintemute, professor of emergency medicine and director of the UC Davis Violence Prevention Research Program. "Our study found that people with convictions for violent misdemeanor crimes who subsequently purchased handguns have very high rates of arrest for firearm-related or violent crimes later on. We need to consider the merits of prohibiting people convicted of violent misdemeanors from purchasing handguns and consider whether felony charges should be reduced less often."

For the study, Wintemute and colleague Mona Wright reviewed criminal records, linking violent misdemeanor convictions with their original criminal charges. Nearly 40 percent of the 787 individuals in the study had misdemeanor convictions resulting from felony charges. The overwhelming majority of records were for men (96.2 percent), with most (47.8 percent) having only one prior conviction of any type. Twenty-five percent had two prior convictions and 27 percent had three or more.

Within this group, Wintemute then identified those who purchased handguns and had California arrests within three years of the handgun purchase. Of the 699 records available for follow up, 34.5 percent of individuals were arrested -- 23.8 percent for violent or firearm-related crimes, such as homicide, rape, robbery and aggravated assault, among others. Age, number of prior convictions and time since the most recent conviction were associated with risk of subsequent arrest. Risk for those originally charged with felonies was similar to that for those originally charged with misdemeanors.

"Nearly 25 percent of subjects who had purchased a handgun were charged with a new firearm-related or violent crime within three years of purchasing a handgun," said Wintemute. In urban counties, the majority (95 percent) of convictions for crimes charged as violent felonies are arrived at through plea bargaining, which commonly involves a reduction from felony to misdemeanor charges. We may be missing an opportunity to prevent those most at risk for committing violent crimes from legally purchasing firearms."

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Story Source: Materials provided by University of California - Davis Health System. Mona A. Wright, Garen J. Wintemute. Firearm Prohibition for Persons Convicted of Violent Crimes. American Journal of Preventive Medicine, 2014