The ctenophore Mnemiopsis leidyi deploys a rapid injury response dating back to the last common animal ancestor.

Regenerative potential is widespread but unevenly distributed across animals. However, our understanding of the molecular mechanisms underlying regenerative processes is limited to a handful of model organisms, restricting robust comparative analyses. Here, we conduct a time course of RNA-seq during whole body regeneration in Mnemiopsis leidyi (Ctenophora) to uncover gene expression changes that correspond with key events during the regenerative timeline of this species. We identified several genes highly enriched in this dataset beginning as early as 10 minutes after surgical bisection including transcription factors in the early timepoints, peptidases in the middle timepoints, and cytoskeletal genes in the later timepoints. We validated the expression of early response transcription factors by whole mount in situ hybridization, showing that these genes exhibited high expression in tissues surrounding the wound site. These genes exhibit a pattern of transient upregulation as seen in a variety of other organisms, suggesting that they may be initiators of an ancient gene regulatory network linking wound healing to the initiation of a regenerative response.

The oldest human fossil in Europe, from Orce (Spain).

The Orce region has one of the best late Pliocene and early Pleistocene continental paleobiological records of Europe. It is situated in the northeastern sector of the intramontane Guadix-Baza Basin (Granada, Andalusia, southern Spain). Here we describe a new fossil hominin tooth from the site of Barranco León, dated between 1.02 and 1.73 Ma (millions of years ago) by Electron Spin Resonance (ESR), which, in combination with paleomagnetic and biochronologic data, is estimated to be close to 1.4 Ma. While the range of dates obtained from these various methods overlaps with those published for the Sima del Elefante hominin locality (1.2 Ma), the overwhelming majority of evidence points to an older age. Thus, at the moment, the Barranco León hominin is the oldest from Western Europe.

Chronological and environmental context of the Middle Pleistocene human tooth from Mollet Cave (Serinyà, NE Iberian Peninsula).

Mollet Cave is a small cave situated in Serinyà (north-east Iberian Peninsula). It was excavated in 1947-48, 1958 and 1972 by Josep M. Corominas. An archaic human molar comes from its base layer (Layer 5). Up till now, this layer has only been dated based on a relative and imprecise chronology of macromammals and the archaeostratigraphic evidence from the early excavations. Recent excavations, conducted between 2001 and 2005, have made it possible to ascertain more precisely the archaeological and palaeontological contents of Mollet Cave, gather microvertebrates, and collect samples for radiometric dating. The aim of this paper is to present the absolute dating of Layer 5, as well as its palaeo environmental and climatic characterisation. The macromammal assemblage seems to have been the result of accumulations produced by the most abundant carnivore, the hyena, which would have used the cave as a den. The results obtained using uranium-series disequilibrium dating ascribe to Layer 5 an age of ca. 215 ka (thousands of years ago), which would correspond to MIS 7. The faunal association suggests a landscape formed by an open and humid woodland characteristic of an interstadial phase, which would have been an environment well suited to sustaining both hyenas and human groups.

Coastal Evolution in a Mediterranean Microtidal Zone: Mid to Late Holocene Natural Dynamics and Human Management of the Castelló Lagoon, NE Spain.

We present a palaeoenvironmental study of the Castelló lagoon (NE Spain), an important archive for understanding long-term interactions between dynamic littoral ecosystems and human management. Combining geochemistry, mineralogy, ostracods, diatoms, pollen, non-pollen palynomorphs, charcoal and archaeo-historical datasets we reconstruct: 1) the transition of the lagoon from a marine to a marginal environment between ~3150 cal BC to the 17th century AD; 2) fluctuations in salinity; and 3) natural and anthropogenic forces contributing to these changes. From the Late Neolithic to the Medieval period the lagoon ecosystem was driven by changing marine influence and the land was mainly exploited for grazing, with little evidence for impact on the natural woodland. Land-use exploitation adapted to natural coastal dynamics, with maximum marine flooding hampering agropastoral activities between ~1550 and ~150 cal BC. In contrast, societies actively controlled the lagoon dynamics and become a major agent of landscape transformation after the Medieval period. The removal of littoral woodlands after the 8th century was followed by the expansion of agrarian and industrial activities. Regional mining and smelting activities polluted the lagoon with heavy metals from the ~11th century onwards. The expansion of the milling industry and of agricultural lands led to the channelization of the river Muga into the lagoon after ~1250 cal AD. This caused its transformation into a freshwater lake, increased nutrient load, and the infilling and drainage of a great part of the lagoon. By tracking the shift towards an anthropogenically-controlled system around ~750 yr ago, this study points out Mediterranean lagoons as ancient and heavily-modified systems, with anthropogenic impacts and controls covering multi-centennial and even millennial timescales. Finally, we contributed to the future construction of reliable seashell-based chronologies in NE Spain by calibrating the Banyuls-sur-Mer ΔR offset with ceramic imports from the Emporiae archaeological site.

Paleobiology and comparative morphology of a late Neandertal sample from El Sidron, Asturias, Spain.

Fossil evidence from the Iberian Peninsula is essential for understanding Neandertal evolution and history. Since 2000, a new sample approximately 43,000 years old has been systematically recovered at the El Sidrón cave site (Asturias, Spain). Human remains almost exclusively compose the bone assemblage. All of the skeletal parts are preserved, and there is a moderate occurrence of Middle Paleolithic stone tools. A minimum number of eight individuals are represented, and ancient mtDNA has been extracted from dental and osteological remains. Paleobiology of the El Sidrón archaic humans fits the pattern found in other Neandertal samples: a high incidence of dental hypoplasia and interproximal grooves, yet no traumatic lesions are present. Moreover, unambiguous evidence of human-induced modifications has been found on the human remains. Morphologically, the El Sidrón humans show a large number of Neandertal lineage-derived features even though certain traits place the sample at the limits of Neandertal variation. Integrating the El Sidrón human mandibles into the larger Neandertal sample reveals a north-south geographic patterning, with southern Neandertals showing broader faces with increased lower facial heights. The large El Sidrón sample therefore augments the European evolutionary lineage fossil record and supports ecogeographical variability across Neandertal populations.