Tarragona Laterality Conference

Next 11 to 13 February at the IPHES, in Tarragona, will hold the “Tarragona Laterality Conference” with invited speakers and discussion around all fields related to hominid and human brain laterality and right-handedness, and their implications for health in modern society. 

This meeting is organized by Dr. Natalie Uomini of University of Liverpool (UK) and Dr. Marina Lozano of IPHES (Spain). This meeting has been organized with founds provided by Leverhulme Trust, Galton Institute and IPHES.

The first and second days will consist of invited experts from different fields related to brain laterality and handedness: Neurobiology, Archaeology, Anthropology, Genetics, Primatology, Psychology...) and poster sessions.

The last day will be an excursion to Mona Foundation to introduce participants to the research being done there.

AIMS: The origin of human brain laterality is a complex issue that is studied by several diverse disciplines. Many different strands of laterality research are currently under way in disciplines that rarely communicate with each other. This will be the first time that all these disciplines will come together for a unique discussion and debate forum to achieve a better understanding of the organization of the human brain since its origin.

We expect to attract researchers and students of Paleoneurology, Primatology, Anthropology, Psychology, Archaeology, Linguistics, Genetics, and Paleoanthropology to this meeting.

Invited speakers:

-         Dr. Richard Byrne (University of St. Andrews, UK)

-         Dr. Chris McManus (University College London, UK)

-         Dr. David Frayer (Kansas University, USA)

-         Dr. Alan Beaton (Swansea University, UK)

-         Dr. John Gowlett (University of Liverpool, UK)

-         Dr. Amandine Chapelain (Université de Rennes, France)

-         Dr. Tim Crow (Oxford University, UK)

-         Dr. Emiliano Bruner (CENIEH, Spain)

-         Dr. Georg Meyer (University of Liverpool, UK)

-         Dr. Linda Marchant (Miami University, USA)

-         Dr. Miquel Llorente (Fundació Mona, Spain)

-         Dr. James Steele (University College of London, UK)

-         Dr. Marina Lozano (IPHES, Spain)

-         Dr. Natalie Uomini (University of Liverpool, UK)

-         Dr. Marina Mosquera (URV-IPHES, Spain)

-         Dr. Ignacio Martínez (UAH, Spain)

-         Dr. Marie-Helène Moncel (IPH, France)

 Contact: Marina Lozano tlatc@iphes.cat

Range of bone modifications by human chewing

In this paper it is present an experimental study of bone modifications caused by human chewing ​​during consumption. Traditionally, tooth marks have been attributed to non-human actors. However, ethnoarchaeological as well as previous experimental work has shown that humans can make many modifications during chewing.

Interest in the identification of human tooth marks is now necessarily increasing, with three lines of research:

1)                  The identification of involvement by hominins (with and without technology) in the formation of faunal assemblages (Pickering and Wallis, 1997; Pobiner et al., 2007; White and Toth, 2007).

2)                  The identification of cannibalism, the most reliable evidence for inference of body consumption (Turner II, 1983; White, 1992; Botella et al., 2000; Andrews and Fernández-Jalvo, 2003; Cáceres et al., 2007; White and Toth, 2007; Fernández-Jalvo and Andrews, 2011).

3)                  The resolution of potential problems of equifinality with chewing damage by other taxa (Martínez, 2007; White and Toth, 2007).

Damages made on bones during hominin feeding can be included in a general pattern that can help us to make inferences about non-cultural signatures produced by hominins/humans. This model included:

(i). Humans can produce a range of modifications similar to carnivores.

(ii). The greatest diversity of modifications is found in flat and/or fragile bones, these modifications are: crenulated and saw-toothed edges, longitudinal crackers, peeling and bend ends. Except for crenulated edges, the other damages are scarce between the products of carnivores. Most carnivores destroy ribs and vertebral apophyses partially or totally (Table 13).

(iii). Crenulated edges made by humans have angular notches. 

Examples of experimental human tooth marks

(iv). Peeling done with the combination of oral and manual force is an unquestionable character of activity requiring prehensile hands. The morphology of the fracture is no different to that described by White (1992). In these cases, the incisors are used, as is done by chimpanzees (Pickering, 2002; Saladié, 2009), like clamps to hold the bone and most of the movement is done with one hand. In most cases small pits and scores are found close to the edge of fracture. Crushing and longitudinal fissures are often found associated with peeling. These partnerships allow us to attribute the tooth marks to anthropogenic consumption with certainty.

(v). Longitudinal cracks and crushing are common in flat bones. These modifications are the result of pressure exerted by biting with large occlusal surfaces. The most effective way to break hard materials and plastics is a contact area as small as possible to maximize the strength of the discharge (Strait, 1997). When the bite is exercised with larger surfaces and various points of contact, force is dispersed, resulting in small fractures that develop into cracks. Similarly, it is possible that this type of large surface biting causes those tooth marks where the perimeter is incomplete.

(vi). Furrowing on the epiphyses is usually slight. Scooping-out, although possible is scarce, and does not always leads to the consumption of spongy tissue. The fractures edges not show licking. In the very small size animals such as rabbits may be more common resulting in shaft cylinders.

(vii). Tooth marks (scores, pits and punctures) are also more abundant on flat bones. Humans rarely produce perforations and punctures.

(viii). Pits may be crescent-shaped.

(ix). Some scores show flaking on the edges and bottom of the scores along their length. Others scores exhibit occasionally internal micro-striation.

The results

 The results suggest that the range of damage is as extensive as that most likely to be produced by carnivores. This damage includes furrowing, scooping-out, crenulated and saw-toothed edges, longitudinal cracking, crushing, peeling and tooth marks. In this paper we present a description of the types of damage observed in the experimental sample. Some of this damage shows parallels between the experimental modifications and archaeological assemblages from Pleistocene and Holocene deposits at the Sierra de Atapuerca sites (Burgos, Spain). The repetition of morphologies allowed us to attribute some of the damage to tooth marks made by human chewing.

For further information:

Saladié, P., et al., “Range of bone modifications byhuman chewing”, Journal of Archaeological Science (2012), 

Contact

Palmira Saladié

psaladie@iphes.cat

Neanderthal Home Spatial and Social Behaviours

The volume number 247 of Quaternary International intituled “Neanderthal Home Spatial and Social Behaviours” resulted from the International Workshop “The Neanderthal Home: Spatial and Social Behaviour” organized by the IPHES (Institut Català de Paleoecologia Humana i Evolució Social) on October 2009 at Tarragona (Spain). The 100th anniversary of the discovery of the Abric Romaní site, an event that is in keeping with the beginning of research on Prehistory in the Iberian Peninsula, and also the celebration of the 25 years of excavation of the IPHES research team at the site, was the perfect occasion and opportunity to organize this meeting.

Neanderthals cannot be understood and discussed without considering the research carried out on the Abric Romaní archaeological site. It is one of the most relevant Middle Palaeolithic sites, with a long and well studied sequence of more than 30,000 years of continues occupation by Neanderthals groups.

This meeting made it possible to gather some of the most foremost international specialists. It also offered the perfect opportunity to discuss and update the most significant research topics on Neanderthal behaviours, and provided new information about the behaviour and the social and spatial organization of this extinct human population. More than 60 scientists from all over the world, specialists in different areas, contributed presentations about these topics to the conference. New data from archaeological sites in France, Germany, South Africa, Italy, Caucasus, Belgium, Israel, Gibraltar, Jordan, and Spain were discussed during the workshop and are published in this monographic volume.

This volume is intended to represent the variability of approaches in current Neanderthal behaviour research, and the great potential of these topics and methodologies for understanding the human past. It tried to accommodate a diversity of opinions and perspectives that reflect the plurality of viewpoints among contemporary researchers. The ranges of topics covered include genetics, dating, paleoecology, geoarchaeology, micromorphology, zooarchaeology, taphonomy, lithic technology, spatial pattern analysis, and paleoanthropoloy, among others. The contributors to this volume provide important new insights that help us to better appreciate and understand the Neanderthals.

For further information:

Chacón, M. G., Vaquero, M., Carbonell, E., 2012. “The Neanderthal Home: spatial and social behaviours”. Quaternary International 247: 1-9.

Burjachs, F., López-García, J.M., Allué, E., Blain, H.-A., Rivals, F., Bennàsar, M., Expósito, I. (2012) Palaeoecology of Neanderthals during Dansgaard-Oeschger cycles in northeastern Iberia (Abric Romaní): From regional to global scale. Quaternary International 247: 26-37.

Courty, M.-A., Carbonell, E., Vallverdú Poch, J., Banerjee, R. (2012) Microstratigraphic and multi-analytical evidence for advanced Neanderthal pyrotechnology at Abric Romani (Capellades, Spain). Quaternary International 247: 294-312.

Rosell, J., Cáceres, I., Blasco, R., Bennàsar, M.L., Bravo, P., Campeny, G., Esteban-Nadal, M., Fernández-Laso, M.C., Gabucio, M.J., Huguet, R., Ibañez, N., Martín, P., Rivals, F., Rodríguez-Hidalgo, A., Saladié, P. (2012) A zooarchaeological contribution to establish occupational patterns at Level J of Abric Romaní (Barcelona, Spain). Quaternary International 247: 69-84.

Vallverdú, J., Alonso, S., Bargalló, A., Bartrolí, R., Campeny, G., Carrancho, Á., Expósito, I., Fontanals, M., Gabucio, J., Gómez, B., Prats, J.M., Sañudo, P., Solé, Á., Vilalta, J., Carbonell, E. (2012) Combustion structures of archaeological level O and mousterian activity areas with use of fire at the Abric Romaní rockshelter (NE Iberian Peninsula). Quaternary International 247: 313-324.

Vaquero, M., Chacón, M.G., García-Antón, M.D., Gómez de Soler, B., Martínez, K., Cuartero, F. (2012) Time and space in the formation of lithic assemblages: The example of Abric Romaní Level J. Quaternary International 247: 162-181.

Contact

M. Gema Chacón

gchacon@iphes.cat

Human Neoteny Revisited : The Case of Synaptic Plasticity

The process of learning requires morphological changes in the neuronal connections and the formation of new synapses. The key mechanism by which different forms of memory are encoded, processed and stored in the brain is modulated depending on the activity, strength and structure of specific synaptic connections. Long-term memory requires changes in genetic expression, which induce the growth of new synaptic connections.

Due to the importance of memory and learning in our species, some authors had suggested that the synaptic plasticity in a number of association areas is higher in the human brain than in the other primates.

Cortical neurons in mammals are characterized by higher metabolism and synaptic plasticity and activity during development and the juvenile stage than in the adult.

In Homo sapiens, brain development is retarded compared with other primates, especially in some association areas, and the rate of brain growth in humans in the postnatal period is much higher than the rate of cerebral growth in non human primates, including chimpanzees. The prolongation of cerebral growth and fetal growth rates during infancy and childhood explains the large brain size in Homo sapiens.

Some association areas in the human brain are characterized by the presence of neurons, which remain structurally immature throughout their lifespan and show an increase in the expression of the genes which deal with metabolism and the activity and synaptic plasticity in the adulthood. High degrees of synaptic plasticity and activity in association areas of the adult human brain seem to have been retained through an increase in the expression of certain genes, many of which are related to cerebral development and, to a lesser extent, through the positive selection of certain genetic variants. Adult human beings are similar to juvenile chimpanzees in terms of their cerebral genetic expression profiles. Neotenic changes only affected a limited group of genes expressed in the brain, which suggests mosaic evolution.

Prefrontal cortex

Aerobic glycolisis in the adult human brain, which seems to be related to an increase in synaptic activity and plasticity, is significantly elevated in certain areas of the cortex of association which have undergone considerable modification during the evolution of human species, as the dorsolateral prefrontal cortex, which is associated with working memory, and a group of areas that make up the brain’s default mode network, which display elevated activity when the individual is at rest and is related to autobiographical memory, planning, and functions related to social interaction and navigation, such as theory of the mind and moral decision making.

Neurons belonging to certain areas of the human cerebral cortex exhibit a higher metabolism and a higher degree of synaptic plasticity and activity in adulthood than the cortical neurons of other mammals. So it appears that human neurons belonging to particular association areas retain juvenile characteristics throughout adulthood, which suggests that a neuronal neoteny has occurred in Homo sapiens, which allows the human brain to function, to a certain degree, like a juvenile brain during adult life.

The increase in the aerobic metabolism in these neurons may lead, however, to higher levels of oxidative stress, therefore favouring the development of neurodegenerative diseases which are exclusive, or almost exclusive, to humans, such as frontal dementia and Alzheimer’s disease, which may be, in part, the result of the retention of juvenile characteristics in adulthood in neurons associated with learning, memory and other complex cognitive functions, and the price our species pay for our elevated cognitive capacity, our longevity and our advanced social intelligence.

For further information:
Bufill, E., Agustí, J., Blesa, R., 2011. "Human Neoteny Revisited: The Case of Synaptic Plasticity". American Journal of Human Biology. 23: 729-739-284.

Contact
Enric Bufill
ebufill@telefonica.net

Continuity of the first human occupation in the Iberian Peninsula: Closing the archaeological gap

The recent discovery of a site at Vallparadís (Terrassa), dated to the upper boundary of the Jaramillo sub-chron (0.98 Ma), allows us to close the archaeological gap of the Late Lower Pleistocene in the Iberian Peninsula—between Orce and Sima del Elefante (1.4-1.3 to 1.2 Ma), on the one hand, and TD6 (0.78 Ma), on the other—and to propose the hypothesis that Western Mediterranean Europe may have been continuously inhabited by humans from 1.4-1.2 Ma until the early Middle Pleistocene. The Iberian Peninsula was home to a stable human settlement throughout the time range in question. This hypothesis would seem to be supported by the number of sites already discovered, their chronology, their ecosystem diversity and, especially, the similar technological and adaptive characteristics they represent.

Fig. 1. Geographic location of the Lower Pleistocene archaeological sites of the Iberian Peninsula and summary of the lithostratigraphy and chronology of the Vallparadís site. IPHES

Taking into account that the lithic technology, adaptive strategies and even biological characteristics of the hominids (in the case of Atapuerca) have certain characteristics in common at Sima del Elefante, Orce, Vallparadís and TD6, we conclude that the first groups of hominids in Europe were capable of successfully withstanding the different climatic conditions that they encountered, thereby ensuring the continuity of human settlement in Europe throughout the Lower Pleistocene. They were able to do this thanks to certain adaptive strategies based on a Mode 1 technological capacity and group social cohesion. These strategies enabled them to eat meat by gaining primary access to herbivore carcasses and successfully compete with large carnivores (e.g. Panthera gombaszoegensis and Pachycrocuta brevirostris at Vallparadís). These first hominids succeeded in hoisting themselves to the top of the food chain, and in doing so guaranteed the continuity of human settlement.

For further information:

Garcia, J., Martínez, K., Carbonell, E., 2011. "Continuity of the first human occupation in the Iberian Peninsula: Closing the archaeological gap". C.R. Palevol. 10 (4), 279-284.

Contact

Joan Garcia
jgarcia@prehistoria.urv.cat

Kenneth Martínez
kmartinez@prehistoria.urv.cat