details courtyard Alhambra

Unknown details identified in the Lions' Courtyard at the Alhambra

Through drawings, researchers from the University of Seville, the École Polytechnique Fédérale de Lausanne (Switzerland) and the University of Granada have identified details hitherto unknown in the muqarnas of the temples of the Lions' Courtyard at the Alhambra in Granada, a UNESCO World Heritage Site.
templetes Patio de los Leones Alhambra Granada, España
Lions' Courtyard at the Alhambra, Granada (Spain)

In order to better understand and facilitate the conservation of these fourteenth-century architectural elements, following a review of numerous repairs performed over the intervening centuries, a novel methodology was followed based on three complementary graphic analyses: first, outstanding images from the seventeenth to the twentieth centuries were reviewed; then new computer drawings were made of their muqarnas, following the theoretical principles of their geometrical grouping; and finally, a three-dimensional scan was made to ascertain their precise current state from the point cloud obtained.

The comparison of drawings has allowed us to verify for the first time that the muqarnas of the two temples have a different configuration and different number of pieces. In addition, geometric deformations have been detected in the original Nasrid design, identifying hitherto unknown pieces, plus other deformations due to the various repairs from major threats that the temples and their muqarnas have survived for centuries, despite their fragile construction.

"For the first time, this article documents and analyses details that were hitherto practically absent from the scientific literature", says Antonio Gámiz, professor at the University of Seville and co-author of this work.

The muqarnas are one of the most unique architectural episodes of the Nasrid Alhambra and of medieval Islamic art because of their sophisticated three-dimensional geometrical construction. They are small prisms that are grouped together and create a great diversity of spatial configurations, adapting their composition to very diverse architectural situations in cornices, arches, capitals and vaults. They reached a virtuous zenith during the reign of Muhammad V (1354-1359 and 1362-1391) when crucial works were undertaken in the palaces of the Alhambra.

This research was supported by the Patronato de la Alhambra and Generalife.

Full bibliographic information

Antonio Gámiz Gordo; Ignacio Ferrer Pérez-Blanco; Juan Francisco Reinoso Gordo (2020): The Pavilions at the Alhambra's Court of the Lions: Graphic Analysis of Muqarnas. Sustainability, 12 (16), 6556 (Special Issue Cultural Heritage and Natural Disasters) MDPI, Switzerland. ISSN 2071-1050. DOI: 10.3390/su12166556

Press release from the Universidad de Sevilla and the Universidad de Granada on the study that has identified details hitherto unknown in the muqarnas of the temples of the Lions' Courtyard at the Alhambra in Granada.


molar size hominins

New study of molar size regulation in hominins

New study of molar size regulation in hominins

The Dental Anthropology Group at the CENIEH has tested the inhibitory cascade model to see whether it explains the size relationships and differences in shape between the different kinds of teeth, in the molar sample from the individuals identified at the Sima de los Huesos site in the Sierra de Atapuerca.
Mandíbula AT-1 de la Sima de los Huesos. Credits: Mario Modesto

The molar size relationship is one of the peculiar characteristics of the different species of hominins and various theories have been proposed to account for this, as well as the differences in shape between the different kinds of teeth (incisors, canines, premolars and molars). The latest theory, called the inhibitory cascade model, arose out of experiments with mice embryos, and in 2016 it was applied theoretically to fossil hominins, with satisfactory results.

It appeared that all hominins satisfy the inhibitory cascade model. In a paper by the Dental Anthropology Group at the Centro Nacional de Investigación sobre la evolución Humana (CENIEH), published recently in the Journal of Anatomy, this model was tested on the molar sample from the individuals identified at the Sima de los Huesos site, situated in the Sierra de Atapuerca (Burgos).

The results match the model generated in mice extraordinarily well, thus confirming the theory's utility once more. “Nevertheless, our conclusions have brought out an anomaly in the model, when it is applied to the oldest species of the genus Homo”, explains José María Bermúdez de Castro, Paleobiology Program Coordinator at the CENIEH and lead author of this work.

Increasing and decreasing patterns

In the genera Ardipithecus, Australopithecus and Paranthropus, as well as in Homo habilis, the size pattern is increasing and fits the premises of the inhibitory cascade model perfectly. The same thing happens in Homo sapiens, except that the pattern is decreasing, with the first molar larger than the second, which in turn is bigger than the third one (wisdom tooth).

Application of the inhibitory cascade model had led to the assumption that the switch from increasing to decreasing pattern would have arisen a little under two million years ago, perhaps coinciding with the transition between the genera Australopithecus and Homo. “However, in our work we noticed that this change could have required at least a million years to take place”, states Bermúdez de Castro.

The hominins from the Sima de los Huesos, which are around 430,000 years old, are a good example of that transition, whereas most specimens of Homo ergaster, Homo erectus, Homo antecessor and Homo heidelbergensis, as well as other species, do not fit the inhibitory cascade model. “Our idea is to continue our research to determine which genetic mechanisms lie behind this anomaly in the model”, says Bermúdez de Castro.

Full bibliographic information

Bermúdez de Castro et al. 2020. Testing the inhibitory cascade model in the Middle Pleistocene Sima de los Huesos (Sierra de Atapuerca, Spain) hominin sample. Journal of Anatomy. DOI: 10.1111/joa.13292
Press release from CENIEH.

The temporal lobes of Homo erectus were proportionally smaller than in H. sapiens

The temporal lobes of Homo erectus were proportionally smaller than in H. sapiens

The CENIEH has contributed to a paleoneurological study published in the journal Quaternary International, on the brain of Homo erectus, which analyzes its temporal lobes and compares these with other species like H. ergaster and H. sapiens
temporal lobes erectus sapiens ergaster
Pearson at al.

Emiliano Bruner, a paleoneurologist at the Centro Nacional de Investigación sobre la Evolución Humana (CENIEH), has participated in a study published in the journal Quaternary International, on the anatomy of the temporal lobes in the brain of Homo erectus, which establishes that they were proportionally smaller than in modern humans.

In H. sapiens, the temporal lobes are relatively more highly developed than in other primates, although little is known about their anatomy in extinct human species, because they are housed in a very delicate region of the cranium known as the middle cranial fossa, which is often not conserved in fossil individuals.

An earlier study by the same team had shown that the size of the middle cranial fossa can be used to deduce the volume of the temporal lobes. In this new study, three anatomical diameters were analyzed in fossils of H. erectus and H. ergaster, and compared with the corresponding measurements for 51 modern humans. The results suggest that both fossil species had temporal lobes proportionally smaller than in humans today.

Moreover, “The Asiatic individuals, namely Homo erectus, had larger temporal lobes than in the African ones, Homo ergaster, although the scanty fossil record does not allow us to tell whether this is due to chance or a paleoneurological difference between the two species”, says Bruner.

As the temporal lobe is a brain region involved in the integration of many cognitive functions, such as memory, the emotions, hearing, social relations and language, any change in their sizes or proportions is of transcendent importance, as this could reveal variations in the development of their neurons or their connections, and therefore in the cognitive functions associated to this region of the cerebral cortex.

This study has been conducted by Alannah Pearson, a doctoral student of Emiliano Bruner at the Australian National University in Canberra (Australia), in collaboration with Professor David Polly, of Indiana University (USA).

 

Full bibliographic information

Pearson, A., Polly, P. D., & Bruner, E. (2020). Temporal lobe evolution in Javanese Homo erectus and African Homo ergaster: inferences from the cranial base. Quaternary International (0). doi: 10.1016/j.quaint.2020.07.048.

 

Press release from CENIEH


cultura muerte neandertales humanos modernos Nohemi Sala culture death neanderthals humans

Does the culture of death predate the Neanderthals and modern humans?

Does the culture of death predate the Neanderthals and modern humans?

The CENIEH researcher Nohemi Sala has been awarded 1.5 million euros by the European Research Council through an ERC-Starting Grant, to scour the fossil record for the roots and evolution of our ancestors' funerary behavior.

cultura muerte neandertales humanos modernos Nohemi Sala
Nohemi Sala, ERC-Starting Grant proyect IP.Credits: N. Sala

All societies existing today possess some kind of funerary culture, and this is one of the behaviors that takes us closest to how complex the human mind is. However, the emergence of this behavior is one of the most controversial topics in the field of human evolution. When did our ancestors start to acquire a culture of death? How was this behavior manifested over time and space? Did this practice appear independently in different species?

There are different ways to tackle these questions, and the more specific one of whether the culture ofdeath precedes Neanderthals and anatomically modern humans. To date, analyses in Paleolithic archaeology have centered on the archaeological context: that is, whether skeletons are preserved completely, the existence of a grave cut or whether objects that could be interpreted as symbolic elements or grave goods are present. This vision restricts funerary behavior almost exclusively to burials, something that was exceptionally rare before the Late Pleistocene, which began 127,000 years ago.

Thus, there is a need to find new methodological approaches so that what has been preserved up to our own time is right at the center: human bones. The European fossil record is a fundamental source of information due to the abundance of fossil skeletons. This is where forensic taphonomy, a discipline that can help to shed light on fundamental issues in this field, comes in. Applying this would be something like carrying out “autopsies” of human fossils to try to learn how they died and, above all, what happened to the remains of the individual between death and modern excavation.

This line of research has crystallized in a project entitled DEATHREVOL. The roots and evolution of the culture-of-death. A taphonomic research of the European Paleolithic record, which has been selected to receive financing under the European Union's Horizon 2020 Research and Innovation program, and which will be conducted over the next five years at the Centro Nacional de Investigación sobre la Evolución Humana (CENIEH).

“This is the first large-scale project centering on an exhaustive taphonomic study of the European fossil record”, explains the CENIEH taphonomy specialist Sala, a member of the Atapuerca research team and a researcher under the Juan de la Cierva-Incorporación program, who has obtained 1.5 million euros in funding for this project submitted to the 2020 call.

Carrying this out will require the participation of a large team of academics and a network of methods which include taphonomic analyses, virtual reconstructions for forensic analyses, studying spatial distribution patterns, the overall relations between different sites and mathematical models to interconnect the broad spectrum of data compiled.

Highly competitive projects

The European Research Council (ERC) projects known as “Starting Grants” are aimed at early-career researchers with post-doctoral experience of between 2 and 7 years, who have an outstanding research record and submit an excellent scientific project on the frontiers of knowledge. These are considered the most prestigious awards in the sphere of European research and, therefore, are highly competitive.

In the 2020 call, 436 researchers from 25 countries in the European Union and associated countries were selected, and 23 of the projects will be conducted at Spanish research centers. Of these 23, four are in the field of humanities and only one is centered on Paleoanthropology.

 

Press release from CENIEH on the Starting Grant for the research about the culture of death preceding Neanderthals and modern humans.