I was born in Lleida in 1962. I graduated in Geology in 1986 at the University of Barcelona, and in 1991 I finished my Ph.D.Thesis on fossil insects and exceptional conservation sites. Since 1993 I have been professor of Paleontology at the University of Barcelona and since 2005 I manage an international team of researchers who work in a multidisciplinary way the Cretaceous amber of the western margin of Tethys. Phone: 34+93+4021381 Address: Dept. Earth and Ocean Dynamics, Faculty of Earth Sciences, University of Barcelona, Marti i Franques s/n 08028 Barcelona
Although specimens in fossil to Recent resins are remarkable for their fidelity of preservation, ... more Although specimens in fossil to Recent resins are remarkable for their fidelity of preservation, amber is well known and studied, unlike the younger resins as Pleistocene copal (2.58–0.0117 Ma) and Holocene copal (0.0117 Ma–1760 AD), or Defaunation resin, which is resin produced after 1760 AD. However, the scientific relevance of these younger resins preserving arthropods that lived in pre-Anthropocene time is often underestimated. Here, we present specimens of workers of stingless bees included in copal and Defaunation resin, from the coastal vichaka forests in Tanzania, and from northwest Madagascar, ranging in age from almost 3000 BP years to only 80 ± 30 BP years and from 2015, respectively. Three known species Hypotrigona gribodoi, Liotrigona bouyssoui, and Liotrigona nilssoni and two new species Axestotrigona kitingae sp. nov. and Hypotrigona kleineri sp. nov. have been discovered from 36 studied specimens. We also noted that the holotype of Trigona richardsi is a junior subjective synonym of Axestotrigona ferruginea ferruginea. The coastal forests in the East Africa region and in East Madagascar are now highly fragmented so that we can expect that the new species are already extinct. Here we demonstrate that the study of inclusions in copal and Defaunation resin can document losses of local biodiversity resulting, for example, from deforestation and they also bring proof of this potential anthropic defaunation.
XXIII Bienal de la Real Sociedad espanola de Historia Natural en Barcelona del 4 al 7 de septiemb... more XXIII Bienal de la Real Sociedad espanola de Historia Natural en Barcelona del 4 al 7 de septiembre de 2019
The Fourier Transform InfraRed spectroscopy (FTIR) analyses of five amber specimens found in the ... more The Fourier Transform InfraRed spectroscopy (FTIR) analyses of five amber specimens found in the archaeological excavations carried out in Chamber II of Las Caldas cave (Province of Asturias, North of Spain), during 1983, 1984, 1988 and 1991, has been accomplished. These specimens, from the Middle to Upper Magdalenian (Upper Palaeolithic), are two non-manipulated amber fragments of polygonal shape, a slab of amber with anthropic scratches and an opaque cortex, a fragment of a stalactite-shaped piece, and one piece strongly fragmented. The FTIR spectra of the non-degraded amber parts have been compared with those of the paleontological ambers from El Caleyu, Alto de El Caleyu and Pruvia sites, which are located a few kilometres from the Las Caldas cave. The comparison allowed us to conclude that the provisioning of the amber by the hunter-gatherer groups of the Las Caldas cave during the Magdalenian was local, and in consequence the amber was not originally from the North of Europe (Baltic region). The characteristics ofthe opaque cortex that is present in one of the pieces, which has been studied under scanning electron microscopy (SEM), indicate that the cortex corresponds to those commonly present in the Cretaceous amber from Europe and that it originated during the Cretaceous due to the grown of a mycelium of a resinicolous fungi from the external surface of the resin pieces towards the interior. This is complementary evidence indicating the local origin of the Las Caldas amber.
Chemical analysis of amber, copal, and resin is a valuable tool for interpreting the botanic orig... more Chemical analysis of amber, copal, and resin is a valuable tool for interpreting the botanic origin of amber and the ecological role of resin in ancient forests. Here we investigated for the first time the volatile and semi-volatile composition of Cretaceous amber, as well as copal and Defaunation resin produced by trees of the family Araucariaceae (Gymnospermae: Pinidae), via solid-phase microextraction gas chromatography-mass spectrometry. Principal component analysis (PCA) revealed a clear distinction between the Pleistocene copal/Defaunation resin and the much older Cretaceous amber samples. However, even among the younger resin samples whose plant producers were identified to the species level, the PCA did not clearly distinguish the groups, either at the species level or at the genus level. Therefore, even with ideal preservation of original chemistry, PCA of SPME GC/MS data will not differentiate varying botanic origins in the Cretaceous amber samples. There was extensive variation observed in the composition of the amber samples, but no separate groups in the PCA. This amber chemistry was most likely influenced by multiple factors, such as variable original resin chemistry and variable maturation as the most relevant. The Cretaceous amber deposits are proposed to represent forests with multiple taxa (even multiple families) of resin-producing trees, which varied over space and time, rather than representing a widespread and homogenous forest. As resin composition is strongly affected by both taxonomy of the resin-producing tree and ecological factors such as herbivory and pathogens, we propose that these forests were exposed to varying combinations of ecological factors
A state of the art of the Barremian Konservat-Lagerstätte of la Pedrera de Meià site (Southern Py... more A state of the art of the Barremian Konservat-Lagerstätte of la Pedrera de Meià site (Southern Pyrenees) is compiled here including the acquisition of new geological data. The relevance of this site, together with the nearby la Cabroa site, is due to its paleobiotic richness and the fact that 113 holotypes and paratypes of flora and fauna have already been defined. Since its discovery at the end of the 19th century and its exploitation as a lithographic limestone quarry, the site has been the object of paleontological interest by national and foreign research teams that are summarized here (including the catalogue of 223 publications). A survey of the existing type specimens in collections all over Europe is also provided, being France and Germany, the countries where more fossils are hosted other than Spain. The geological frame of this site is also reviewed, by revisiting unpublished geological mappings (mainly that of Krusat, 1966) and integrating it in a comprehensive map that i...
Although specimens in fossil to Recent resins are remarkable for their fidelity of preservation, ... more Although specimens in fossil to Recent resins are remarkable for their fidelity of preservation, amber is well known and studied, unlike the younger resins as Pleistocene copal (2.58–0.0117 Ma) and Holocene copal (0.0117 Ma–1760 AD), or Defaunation resin, which is resin produced after 1760 AD. However, the scientific relevance of these younger resins preserving arthropods that lived in pre-Anthropocene time is often underestimated. Here, we present specimens of workers of stingless bees included in copal and Defaunation resin, from the coastal vichaka forests in Tanzania, and from northwest Madagascar, ranging in age from almost 3000 BP years to only 80 ± 30 BP years and from 2015, respectively. Three known species Hypotrigona gribodoi, Liotrigona bouyssoui, and Liotrigona nilssoni and two new species Axestotrigona kitingae sp. nov. and Hypotrigona kleineri sp. nov. have been discovered from 36 studied specimens. We also noted that the holotype of Trigona richardsi is a junior subjective synonym of Axestotrigona ferruginea ferruginea. The coastal forests in the East Africa region and in East Madagascar are now highly fragmented so that we can expect that the new species are already extinct. Here we demonstrate that the study of inclusions in copal and Defaunation resin can document losses of local biodiversity resulting, for example, from deforestation and they also bring proof of this potential anthropic defaunation.
XXIII Bienal de la Real Sociedad espanola de Historia Natural en Barcelona del 4 al 7 de septiemb... more XXIII Bienal de la Real Sociedad espanola de Historia Natural en Barcelona del 4 al 7 de septiembre de 2019
The Fourier Transform InfraRed spectroscopy (FTIR) analyses of five amber specimens found in the ... more The Fourier Transform InfraRed spectroscopy (FTIR) analyses of five amber specimens found in the archaeological excavations carried out in Chamber II of Las Caldas cave (Province of Asturias, North of Spain), during 1983, 1984, 1988 and 1991, has been accomplished. These specimens, from the Middle to Upper Magdalenian (Upper Palaeolithic), are two non-manipulated amber fragments of polygonal shape, a slab of amber with anthropic scratches and an opaque cortex, a fragment of a stalactite-shaped piece, and one piece strongly fragmented. The FTIR spectra of the non-degraded amber parts have been compared with those of the paleontological ambers from El Caleyu, Alto de El Caleyu and Pruvia sites, which are located a few kilometres from the Las Caldas cave. The comparison allowed us to conclude that the provisioning of the amber by the hunter-gatherer groups of the Las Caldas cave during the Magdalenian was local, and in consequence the amber was not originally from the North of Europe (Baltic region). The characteristics ofthe opaque cortex that is present in one of the pieces, which has been studied under scanning electron microscopy (SEM), indicate that the cortex corresponds to those commonly present in the Cretaceous amber from Europe and that it originated during the Cretaceous due to the grown of a mycelium of a resinicolous fungi from the external surface of the resin pieces towards the interior. This is complementary evidence indicating the local origin of the Las Caldas amber.
Chemical analysis of amber, copal, and resin is a valuable tool for interpreting the botanic orig... more Chemical analysis of amber, copal, and resin is a valuable tool for interpreting the botanic origin of amber and the ecological role of resin in ancient forests. Here we investigated for the first time the volatile and semi-volatile composition of Cretaceous amber, as well as copal and Defaunation resin produced by trees of the family Araucariaceae (Gymnospermae: Pinidae), via solid-phase microextraction gas chromatography-mass spectrometry. Principal component analysis (PCA) revealed a clear distinction between the Pleistocene copal/Defaunation resin and the much older Cretaceous amber samples. However, even among the younger resin samples whose plant producers were identified to the species level, the PCA did not clearly distinguish the groups, either at the species level or at the genus level. Therefore, even with ideal preservation of original chemistry, PCA of SPME GC/MS data will not differentiate varying botanic origins in the Cretaceous amber samples. There was extensive variation observed in the composition of the amber samples, but no separate groups in the PCA. This amber chemistry was most likely influenced by multiple factors, such as variable original resin chemistry and variable maturation as the most relevant. The Cretaceous amber deposits are proposed to represent forests with multiple taxa (even multiple families) of resin-producing trees, which varied over space and time, rather than representing a widespread and homogenous forest. As resin composition is strongly affected by both taxonomy of the resin-producing tree and ecological factors such as herbivory and pathogens, we propose that these forests were exposed to varying combinations of ecological factors
A state of the art of the Barremian Konservat-Lagerstätte of la Pedrera de Meià site (Southern Py... more A state of the art of the Barremian Konservat-Lagerstätte of la Pedrera de Meià site (Southern Pyrenees) is compiled here including the acquisition of new geological data. The relevance of this site, together with the nearby la Cabroa site, is due to its paleobiotic richness and the fact that 113 holotypes and paratypes of flora and fauna have already been defined. Since its discovery at the end of the 19th century and its exploitation as a lithographic limestone quarry, the site has been the object of paleontological interest by national and foreign research teams that are summarized here (including the catalogue of 223 publications). A survey of the existing type specimens in collections all over Europe is also provided, being France and Germany, the countries where more fossils are hosted other than Spain. The geological frame of this site is also reviewed, by revisiting unpublished geological mappings (mainly that of Krusat, 1966) and integrating it in a comprehensive map that i...
BCN Rocks is an application (App) for personal mobile devices (Android and iOS versions) suitable... more BCN Rocks is an application (App) for personal mobile devices (Android and iOS versions) suitable for secondary and high school students as well as people without background in Earth Sciences. The main objective of this App is to learn geology using the city facades and pavements of two emblematic spaces of the city of Barcelona, the Passeig de Gràcia and the Barri Gòtic. The application has three main sections (ELEMENTS, EXPLORE, and LABORATORY) that are intended to satisfy the different needs of users. In the first section, Elements, the user will find all the information about rocks forming the selected buildings as well as a brief explanation about the history and architecture of each edifice. The second section, Explore, aims to arise the curiosity of users. In this sense, several routes are proposed according to different criteria including geographic position and age of the edifices. Finally, the third section, Laboratory, allows all users to investigate several geological aspects by means of interactive experiments.
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