Aquesta tesi doctoral tracta sobre l'anomenada controvèrsia de l'Home d'Orce. L'Home d'Orce és un fragment cranial d'uns 8 centímetres atribuït a un homínid i descobert al jaciment de Venta Micena, a Orce, Granada. El fòssil va ser desenterrat l'any 1982 per tres joves paleontòlegs catalans, Josep Gibert, Salvador Moyà-Solà i Jordi Agustí de l'Institut de Paleontologia de Sabadell. Aparentment, el descobriment podia ser científicament revolucionari ja que va ser atribuït a l'homínid europeu més antic. Els tres científics van portar el descobriment als polítics a càrrec de la seva institució. Juntament amb polítics andalusos, una presentació pública del descobriment va ser organitzada al juny de 1983. Quan va ser donat a conèixer, la part interna del fragment seguia enganxada a una roca, pel que no era visible. Malgrat tot, l'Home d'Orce va tenir un gran ressò mediàtic, apareixent a molts diaris, revistes i canals de televisió. La situació política de l'Espanya del moment, al principi de la democràcia, després de 40 anys de dictadura, va ser un factor crucial en la manera en que el descobriment va ser divulgat. L'any següent, la part interna del fragment va ser netejada i una estranya cresta va aparèixer. Aquesta cresta semblava indicar que el fragment no era d'un homínid sinó que pertanyia a un membre de la família dels cavalls antic. Aquesta nova atribució va ser feta pública per primera vegada a la portada del diari El País. A partir d'aquí, una controvèrsia molt pública va esclatar. Només un dels descobridors, Josep Gibert, va mantenir que l'Home d'Orce era d'un homínid. Aquesta polèmica va durar al menys 23 anys, fins 2007, quan Gibert va morir. Amb una narrativa cronològica de la controvèrsia, aquesta tesi vol explorar les interaccions entre científics, periodistes, públic general i polítics. En aquest anàlisi, van sorgir diversos aspectes interessants. Primer, la importància de la situació geogràfica dels científics i dels jaciments i com aquestes van afectar la forma en que el coneixement va ser presentat a la societat. Segon, el paper preponderant interpretat pels discursos i estratègies que els científics d'Orce van utilitzar i que van fer creïbles, o no, determinades teories científiques tan pel públic general com per la comunitat científica. Tercer, la necessitat de considerar les similituds entre la història de l'Home d'Orce i d'altres històries de ciència, per tal de desfer l'etiqueta d'excepció científica que sovint té aquesta controvèrsia. Quart, el paper principal que els polítics en aquesta controvèrsia ens porta a pensar en les moltes maneres per les quals la política esta relacionada amb la ciència. Per acabar, aquesta tesi pretén destacar fins a quin punt la pràctica científica es realitza per els anomenats ‘públics’ de la ciència. En la història de l'Home d'Orce podem veure perfectament com la forma que el coneixement científic agafa va ser completament determinada per la seva posició pública. En definitiva, l'Home d'Orce és un exemple perfecte per entendre com les afirmacions científiques es desenvolupen, negocien i finalment s'accepten (o rebutgen) en públic, i, com a conseqüència, involucrant el públic general, així com els polítics i d'altres actors. / This PhD thesis deals with the so-called Orce Man controversy. The Orce Man is a 8 centimetres cranial fragment attributed to a hominid and discovered in the Venta Micena site, in Orce, Granada, Andalusia, southern Spain. The fossil was unearthed in 1982 by three young Catalan palaeontologists, Josep Gibert, Salvador Moyà-Solà i Jordi Agustí, from the Institut de Paleontologia de Sabadell. Apparently the discovery could be scientifically revolutionary as it was attributed to the earliest European hominid. The three scientists brought the discovery to the politicians in charge of their institution. Together with the Andalusian politicians, a public presentation of the discovery was organized for June 1983. When it was announced, the internal part of the bone was still attached to a rock and, therefore, remained invisible. The Orce Man attracted a great media following with coverage from several newspapers, magazines, and television channels. The political situation in Spain, with democracy just emerging after 40 years of dictatorship, was a crucial factor in the way that this discovery was disseminated. After a year, the internal part of the fragment was cleaned and a strange crest appeared. The crest seemed to indicate that the fragment was not from a hominid but that it belonged to an ancient equine. The new information was first made public on the front page of the El País newspaper. With this, a very public controversy broke out. Only one of the three discoverers, Josep Gibert, stuck to his stance, maintaining that the Orce fragment was indeed a hominid. This dispute lasted for at least 23 years until 2007 when Gibert died. By developing a chronological narrative of the controversy, this thesis wants to explore the interactions between scientists, journalists, the general public, and politicians. In this analysis, several general remarks emerged. First, the importance of the geographic situation of scientists and sites and how this affected the way that knowledge was presented to society. Second, the significant role that the Orce scientists’ discourses and strategies that make certain claims credible or not for both the scientific community and the general public. Third, the necessity to consider the similarities between the Orce Man story and other scientific successful stories, in order to detach from Orce the label of a exception in scientific practice that often is attributed to this controversy. Fourth, the prominent role of politicians in this controversy that let us think about the several ways in which politics are related to science. Finally, this thesis aims to highlight the extent to which scientific practice is related to these so-called ‘publics’ of science. In the Orce Man story we can perfectly see how the shape that scientific knowledge took place was completely determined by its public stance. To sum up, the Orce Man public controversy is a perfect example to understand how scientists claims are developed, negotiated and finally accepted (or rejected) in public, and, therefore, involving the general public as well as politicians and other actors.

La studio della distribuzione spaziale e temporale della associazioni a foraminiferi planctonici, campionati in zone con differente regime idrografico, ha permesso di comprendere che molte specie possono essere diagnostiche della presenza di diverse masse d’acqua superficiali e sottosuperficiali e di diversi regimi di nutrienti nelle acque oceaniche. Parte di questo lavoro di tesi si basa sullo studio delle associazioni a foraminiferi planctonici attualmente viventi nel Settore Pacifico dell’Oceano Meridionale (Mare di Ross e Zona del Fronte Polare) e nel Mare Mediterraneo (Mar Tirreno Meridionale). L’obiettivo di questo studio è quello di comprendere i fattori (temperatura, salinità, nutrienti etc.) che determinano la distribuzione attuale delle diverse specie al fine di valutarne il valore di “indicatori” (proxies) utili alla ricostruzione degli scenari paleoclimatici e paleoceanografici succedutisi in queste aree. I risultati documentano che la distribuzione delle diverse specie, il numero di individui e le variazioni nella morfologia di alcuni taxa sono correlate alle caratteristiche chimico-fisiche della colonna e alla disponibilità di nutrienti e di clorofilla. La seconda parte del lavoro di tesi ha previsto l’analisi degli isotopi stabili dell’ossigeno e del rapporto Mg/Ca in gusci di N. pachyderma (sin) prelevati da pescate di micro zooplancton (per tarare l’equazione di paleo temperatura) da un box core e da una carota provenienti dalla zona del Fronte Polare (Oceano Pacifico meridionale), al fine di ricostruire le variazioni di temperatura negli ultimi 13 ka e durante la Mid-Pleistocene Revolution. Le temperature, dedotte tramite i valori degli isotopi stabili dell’ossigeno, sono coerenti con le temperature attuali documentate in questa zona e il trend di temperatura è paragonabile a quelli riportati in letteratura anche per eventi climatici come lo Younger Dryas e il mid-Holocene Optimum. I valori del rapporto Mg/Ca misurato tramite due diverse tecniche di analisi (laser ablation e analisi in soluzione) sono risultati sempre molto più alti dei valori riportati in letteratura per la stessa specie. La laser ablation sembra carente dal punto di vista del cleaning del campione e da questo studio emerge che le due tecniche non sono comparabili e che non possono essere usate indifferentemente sullo stesso campione. Per quanto riguarda l’analisi dei campioni in soluzione è stato migliorato il protocollo di cleaning per il trattamento di campioni antartici, che ha permesso di ottenere valori veritieri e utili ai fini delle ricostruzioni di paleotemperatura. Tuttavia, rimane verosimile l’ipotesi che in ambienti particolari come questo, con salinità e temperature molto basse, l’incorporazione del Mg all’interno del guscio risenta delle condizioni particolari e che non segua quindi la relazione esponenziale con la temperatura ampiamente dimostrata ad altre latitudini. / Spatial and temporal distribution of modern planktonic foraminifera collected in different oceanographic regimes document that some species are reliable tracers of oceanographic change in surface and subsurface water. In order to determine the factors controlling the distribution of planktonic foraminifera as a proxy for reconstruction of palaeoenvironments, we present data on live assemblages collected in the Southern Ocean (Ross Sea and Polar Front Zone) and in the Mediterranean Sea (Tyrrhenian Sea). Results document that diversity of planktonic foraminifera, number of specimens and variations in test morphology are related to nutrient contents and to regional differences in water properties. Oxygen isotopic composition and Mg/Ca ratios were measured in the planktonic foraminifer Neogloboquadrina pachyderma (sin) from plankton tows (in order to select the paleotemperature equation) from a box core and a core collected in the Southern Ocean in order to reconstruct the temperature variation during the last 13 kyr and during the Mid-Pleistocene Revolution. Temperature estimates from δ18O of Neogloboquadrina pachyderma (sin) are consistent with today’s temperature and record the same trend evidenced in literature. Mg/Ca ratios have been investigated using LA-ICPMS and ultracleaning procedures on ‘bulk’ foraminifera followed by ICP-MS/ICP-AES analysis. Mg/Ca ratios are particularly high for all samples measured by both techniques and correlation of Mg/Ca with calcification temperature are not statistically significant. Laser ablation technique seems to be unsuitable for this kind of samples and in this area. Ultracleaning procedures were improved for polar samples in order to reconstruct paleotemperatures in this area. One more potential hypothesis for anomalous values is that foraminiferal Mg/Ca ratios at the PF of the Pacific Ocean may be significantly influenced by seawater carbonate chemistry, mainly in water masses with polar characteristics, including lower salinity.

The ‘Continental Intercalaire’ deposits of the Tataouine basin of southern Tunisia preserve one of the most diverse Cretaceous vertebrate fauna from Africa. This research project focuses on a detailed revision of the stratigraphic distribution of mid-Cretaceous fossil beds in the Tataouine Basin and includes the description of four, newly discovered vertebrate tracksites. In the Tataouine region, macro- and microvertebrate remains are recovered from three stratigraphic intervals: the lower Douiret Formation (Barremian), the Chenini (rare) and Oum ed Diab members of the Aïn El Guettar Formation (Albian). A detailed, basin-scale revision of the stratigraphic occurrence of fossil-bearing strata indicates 1. lateral facies variability within the context of a low gradient, circalittoral to coastal-plain environment; 2. multiple and diachronous fossil beds which include elasmobranchs, actinopterygians, sarcopterygians, turtles, crocodyliforms, pterosaurs, and non-avian dinosaurs remains. Four vertebrate tracksites have been discovered in the study area: 1. the Middle Jurassic Beni Ghedir site which preserves approximately 130 tridactyl footprints distributed over an area of 200 square meters, representing the oldest evidence of a dinosaur fauna in Tunisia; 2. the late Albian Chenini tracksite, which includes poorly preserved crocodilian tracks and the dinosaur ichnospecies Apulosauripus federicianus; 3. the Cenomanian Ksar Ayaat locality, where footprints assigned to a pleurodiran turtle are exposed, and 4. the upper Cenomanian Jebel Boulouha site which presents almost 100 well-preserved tridactyl tracks referred to small-sized theropods, fossil bird tracks - ichnogenus Koreanaorins – and tracks referred to a mammalian trackmaker, representing the first report of fossil bird and mammal from the Cretaceous of continental Africa and Tunisia respectively. In addition, data collected from the Tunisian tracksites have been compared with coeval tracksites in Italy and Croatia, showing analogies in morphology and paleoenvironment of dinosaur ichnoassociations, supporting the already hypothesized subaerial connection between these areas during the mid-Cretaceous.

Longstanding debates concerning the origin of the Kess Kess Emsian carbonate mounds exposed at Hamar Laghdad Ridge (eastern Anti-Atlas, Morocco) centre around the processes that induced precipitation of carbonate mud and the preservation of steep morphologies. Although in the last years an origin related to hydrothermalism seemed to be more likely, to date the Kess Kess are still considered controversial vent deposits. This study combines in updated research review information from previous work and new detailed field observations coupled with new analytical results to define a consistent framework and some new insight of current knowledge about the origin of these mounds. We obtain a complete minero-petrographic and palaeobiological data set and a detailed geochemical characterization of the different lithologies and facies of the Hamar Laghdad stratigraphic succession, including mounds, and we compared the results with the data from Maïder Basin mounds (Anti-Atlas, Morocco). Our data support the hydrothermal model proposed for the genesis and development of the Kess Kess mounds. The mechanisms linked to the mounds formation and growth are discussed in the light of the new finding of fluid-sediment interaction within a scenario driven by late magmatic fluids circulation. Conical mounds and other fluids related morphologies were also reported from Crommelin crater area (Arabia Terra, Mars). These mounds consist in meter-sized conical buildups hosted in the Equatorial Layered Deposits (ELDs) deposed during a regional groundwater fluid upwelling. Geometries and geological conditions that might have controlled the development of such morphologies were discussed. According to our data the morphological and stratigraphical characteristics of Crommelin area mounds are most consistent with a formation by fluids advection. Then we compare terrestrial and Martian data and examine the geological settings of hydrothermal mound occurrences on Earth in order to describe potential target areas for hydrothermal structures on Mars. / Da quando sono stati descritti per la prima volta i mound conici (Kess Kess) affioranti nello Hamar Laghdad (Anti-Atlante, Marocco), hanno ricevuto interpretazioni discordanti. Sebbene attualmente sembri assodata una dipendenza dalla circolazione di fluidi idrotermali, la loro origine rimane problematica e sono pertanto ambiguamente definiti depositi di vent. Questo progetto ha come obiettivo principale quello di fornire nuove evidenze della genesi dei Kess Kess e della loro interazione con fluidi idrotermali. A questo scopo è stata prodotta una dettagliata descrizione minero-petrografica, paleobiologica e geochimica di tutta la successione stratigrafica corrispondente ai Kess Kess. I dati ottenuti sono stati confrontati con quelli provenienti da mound analoghi ai Kess Kess affioranti nel Maïder Basin per il quali è stata proposta un’origine non legata ad idrotermalismo. I dati in nostro possesso hanno confermato l’influenza di fluidi idrotermali durante la formazione dei Kess Kess e, come previsto, il fattore che controlla la circolazione di fluidi all’interno dei sedimenti è risultato essere un corpo vulcanico alla base dello successione stratigrafica. In una seconda fase della ricerca sono stati descritti alcuni mound conici scoperti di recente Marte nell’area del cratere Crommelin (Arabia Terra). Questi corpi conici sono stati individuati all’interno dei così detti Equatorial Layered Deposits (ELDs) per i quali da tempo è stata suggerita un’origine legata a risalita di fluidi. I risultati ottenuti dalla descrizione di dettaglio dei mound e delle altre morfologie confermano la risalita di fluidi localizzata nelle depressioni costituite dai crateri da impatto come Crommelin. Questa risalita di fluidi oltre ad avere generato i mound e le altre morfologie descritte ha influenzato la geometria dei sedimenti all’interno dei crateri. Il confronto fra mound terrestri e marziani e lo studio di dettaglio di particolari contesti geologici sulla Terra ha permesso di ipotizzare potenziali aree affette da risalita di fluidi su Marte.

En el margen este de la cuenca surpirenaica, la parte superior del Eoceno medio está representada por dos ciclos sedimentarios sucesivos, Collbàs e Igualada. La sedimentación en ambos ciclos fue dominantemente terrígena y sólo esporádicamente tuvo lugar el depósito de carbonatos. En los materiales resultantes se han individualizado diez asociaciones de foraminíferos, que caracterizan sucesivamente las facies de plataforma abierta s.l., bioconstruidas, plataforma protegida y medios litorales. Bioestratigráficamente, los macroforaminíferos presentes en los ciclos Collbàs e Igualada corresponden, respectivamente, a las biozonas SBZ-17 y SBZ-18 (Eoceno medio tardío). Por lo tanto, el Eoceno superior no está representado en el área estudiada por sedimentos marinos, tal como indica la ausencia de macroforaminíferos de la zona SBZ-19. En la parte superior del ciclo Igualada aparecen géneros y/o especies típicas del "Tetis Central", los cuales se interpretan como inmigrantes orientales ya que no se han observado predecesores en el dominio Mediterráneo. / On the eastern margin of the South Pyrenean basin, the late Middle Eocene marine sediments are represented by two successive sedimentary cycles, Collbàs and Igualada. The sedimentation in both cycles was dominated by terrigenous influx and only sporadically carbonate sedimentation took place. Ten paleoenvironmental assemblages of foraminifera have been individualised within these sediments that characterise open marine shelf, reef, lagoonal and litoral facies. In terms of the Shallow Benthic Zonation (SBZ), larger Foraminifera occurring within the Collbàs and Igualada cycles belong to the SBZ-17 and SBZ-18 (late Middle Eocene), respectively. Accordingly, the Upper Eocene is not represented in this area by marine sediments as reflected by the absence of foraminifera from the SBZ-19. In the upper part of the SBZ-18 some genera and/or species typical from the Central Tethys occur; they are interpreted as immigrants from the "Central Tetis", because no predecessors have been observed in the Mediterranean realm.

Los foraminíferos rotálidos, poco conocidos y de difícil identificación, empezaron su diversificación a partir del evento de eutrofización global del Cenomaniense- Turoniense. Estos desarrollaron estrategias K de reproducción, dando lugar a un incremento del tamaño de las conchas y produciendo arquitecturas cada vez más complejas. En los sedimentos del Cretácico Superior de la Cuenca Surpirenaica se han identificado abundantes foraminíferos del grupo de los rotálidos. El estudio detallado de estos ha permitido la identificación de, al menos, nueve formas diferenciadas. Algunas de ellas ya fueron descritas anteriormente en la zona estudiada; otras se citan por primera vez. Se ha detectado, en los sedimentos del Cenomaniense superior, la presencia de Rotorbinella mesogeensis, la cual se ha identificado como el posible progenitor de todos los rotálidos. A partir del Coniaciense superior se produce una explosión de formas, con la aparición de los géneros Iberorotalia, Orbitokathina, Pyrenerotalia, Pararotalia y Rotorbinella. Otro grupo, representado por el género Calcarinella se caracteriza por poseer un sistema de canales envolventes y múltiples aberturas. El único grupo de macroforaminíferos con foramen múltiple en la Cuenca Pirenaica son el grupo de los siderolítidos. Las afinidades de este grupo no son muy claras. Algunas de estas formas desaparecen al iniciarse la fase compresiva Pirenaica; otras consiguen sobrevivir hasta el Cretácico superior tardío con ligeras modificaciones, tanto de tamaño como de estructuras. Además de la descripción de estas formas, también se ha definido la extensión biostratigráfica de estos géneros y especies. / The rotaliids, poorly known and difficult to identify, are diversified for the first time in Earth History after the Cenomanian- Turonian eutrophication event and are seen to develop K strategies, dimorphism of generations, increasing its body sizes and producing complex architectures. In the Upper Cretaceous sediments of South Pyrenean Basin, abundant forms of rotaliid foraminifera have been identified. A detailed study of them has allowed the identification of, at least, nine forms of that group of large foraminifera. Some of them were already described in the studied zone; others are mentioned for the first time. In the Upper Cenomanian sediments, a small rotaliid has been detected, Rotorbinella mesogeensis, that has been identified as the possible ancestor of all the rotaliids. From the Upper Coniacian an explosion of forms takes place, with the apparition of the genus Iberorotalia, Orbitokathina, Pyrenerotalia, Pararotalia and Rotorbinella. Another group, represented by the genus Calcarinella, is characterised by posses an enveloping canal system and multiple aperture. The only larger foraminifera group with multiple foramen in the Pyrenean Basin are the siderolitiids. The affinities with this group are not very clear. Some of these forms disappear when the compressive phase of the Pyrenees formation starts; other are able to survive until Late Upper Cretaceous developing slight morphological and size modifications. Further the description of these forms, their biostratigraphical extension of the genus and species described in this work has been defined.

Los rapidionínidos representan un elemento importante, diverso y abundante en las comunidades de macroforaminíferos porcelanados de aguas poco profundas del Cretácico medio y superior. Su morfología general es muy similar, por lo que es necesario un estudio morfológico detallado para distinguir los géneros y especies en el interior de los diferentes grupos implicados. La revisión de los taxones aquí estudiados ha permitido eliminar ciertas contradicciones e inconsistencias que se han dado en la literatura del grupo, incrementar su potencial valor como fósiles guía y entender mejor el significado de su distribución paleogeográfica. En particular, el uso del nombre genérico de Pseudedomia Henson, 1948, (especie tipo P. multistriata, Maastrichtian) para designar especies del Ciclo de Maduración de la Comunidad (Global Community Maturation cycle, Hottinger 2001) previo, como "P." drorimensis Reiss et al., 1964, (Cenomaniense) o la supuesta sinonimia entre el género caribeño Raadshoovenia guatemalensis Van den Bold, 1946, (de edad supuestamente Paleoceno) y el género tetisiano Cuvillierinella salentina Papetti y Tedeschi, 1965, (Cretácico superior) han sido la causa de las dificultades en la comprensión de la evolución de la familia Rhapydioninidae en el tiempo y el espacio. Para llevar a cabo la revisión de los taxones, se han muestreado las localidades tipo o, cuando ha sido imposible, las localidades equivalentes siempre lo más cercanamente posible a las localidades tipo. En México, para el muestreo se han seguido las indicaciones y descripciones estratigráficas de Pêcheux (1984) y Michaud (1987). En España, se han considerado los trabajos de Martín-Chivelet (1993) para la Cordillera Bética y Calonge (1989) para la Cordillera Ibérica. En Grecia se han seguido los trabajos de Fleury (1974), mientras que el material de Italia fue recolectado por Mariano Parente en los Apeninos. Todos los rapidionínidos proceden de sedimentos extraordinariamente poco profundos. Por consiguiente, su restringido nicho ecológico dificulta una correlación precisa con la escala cronoestratigráfica en general y con la escala biostratigráfica basada en biozonaciones de orbitoídidos en particular. En consecuencia, algunas de las conclusiones taxonómicas dadas a nivel específico se deben considerar provisionales o tentativas. Los resultados de este trabajo confirman en gran medida las observaciones realizadas por Fleury y Fourcade en su trabajo de 1990, el único trabajo publicado en el que se da una visión general del grupo de los rapidionínidos desde que Henson publicara, en 1948, su monografía. / The rhapydioninids represent an important, diverse and abundant element in the shallow-water communities of porcelaneous foraminifera of the Middle and Late Cretaceous. Their general morphology is very similar and called for a careful morphological analysis in order to distinguish the genera and the species within the different groups involved. The revision of the relevant taxa given here permits to eliminate contradictions and inconsistencies in the current literature, to enhance their potential as biostratigraphic index fossils and to understand the significance of their paleogeographic distribution. In particular, the use of the generic name Pseudedomia Henson, 1948, (type species: P. multistriata, Maastrichtian) for species belonging to the previous Global Community Maturation cycle (Hottinger, 2001), such as "P." drorimensis Reiss et al., 1964, (Cenomanian) or the supposed synonymy of the Caribbean Raadshoovenia guatemalensis van den Bold, 1946, (said to be of Paleocene age) with the Tethyan Cuvillierinella salentina Papetti and Tedeschi, 1965, (Late Cretaceous) have produced considerable difficulties to understand the evolution of the rhapydioninid family in time and space. In order to revise the various taxa involved, their type localities or as close equivalents as possible where sampled. In Mexico the stratigraphical descriptions and indications of Pêcheux (1984) and Michaud (1987) were followed. In Spain, we could relay on the work of Martin-Chivelet (1993) for the Betic Cordillera and of Calonge (1989) for the Iberian range. In Greece we founded our sampling on the papers of Fleury (1974), whereas in Italy Mario Parente collected suitable material for our research from the Apennines. All rhapydioninids are found in sediments with an extremely very shallow facies. Thus, their restricted ecological range often hampers a precise correlation with the chronostratigraphic time scale in general and with the ecologically closest biostratigraphic zonation based on orbitoids in particular. Therefore, some of the taxonomic conclusions on the species level must be considered as provisional or tentative. The results of the revisions given here confirm to a large extent the views expressed by Fleury and Fourcade in their paper of 1990, the only comprehensive overview on the group to be found in literature since Henson's monograph in 1948.

La família Hominidae està constituïda pels grans simis antropomorfs (ximpanzés, bonobos, goril·les i orangutans) i els humans. Els primers mostren unes mans molt llargues amb uns polzes relativament curts, degut a les pressions de selecció de la locomoció arbòria. En canvi, la mà dels humans és relativament curta, amb un polze poderós. Aquesta morfologia proporciona un complex repertori de moviments, capacitats de prensió i, molt especialment, una "pinça de precisió" que fa que la mà humana constitueixi una de les estructures més distintives dels humans. La lògica podria fer-nos pensar que les mans curtes dels humans varen derivar a partir de les mans allargades dels actuals grans simis. Ben al contrari, l'estudi dels homínids fòssils del Miocè de Catalunya, com Pierolapithecus i Hispanopithecus, juntament amb la d'altres tàxons fòssils d'arreu del món demostra que els primers homínds tenien mans relativament curtes amb polzes llargs que feien servir per agafar-se de manera segura a les branques dels arbres durant la progressió quadrúpeda i la grimpació vertical. Així doncs, les proporcions de la mà humana són relativament primitives i, de fet, són els grans antropomorfs actuals els que mostren unes mans molt evolucionades cap a un tipus de locomoció arbòria molt especialitzat, la suspensió.Així mateix, les restes fòssils de l'homínid bípede Orrorin tugenensis (de Kènia, amb uns 6 Ma) mostren que la capacitat de manipulació refinada va aparèixer molt aviat en l'evolució humana, en directa relació amb l'aparició del bipedisme terrestre habitual i la consegüent alliberació de les mans de les pressions de selecció locomotores. / Extant great apes (chimpanzees, bonobos, gorillas and orangutans) together with humans constitute the family Hominidae. The former display long hands with short thumbs, due to arboreal locomotion selective pressures. Humans show instead relatively short hands with powerful thumbs that allow their hands to perform a wide spectrum of prehensile capabilities, especially the "precision grip" that constitutes one of the hallmarks of humankind. While it seems plausible to think that the short hands of humans evolved from the long hands of great apes, the study of the Miocene apes (e.g. Pierolapithecus and Hispanopithecus) demonstrate that a relatively short hand with long a thumb, used to assist a powerful grasping during arboreal palmigrady, is the primitive condition from which the elongated hands of extant apes and the somewhat shortened hands from humans evolved.By the way, the fossil remains of the bipedal hominid Orrorin tugenesis (from Kenya, ca. 6 Ma) show that refined manipulation appeared early in human evolution, together with habitual terrestrial bipedalism and the concomitant freeing of the hands from locomotor demands.

La localidad surpirenaica de les Collades de Basturs presenta afloramientos extensos y bien expuestos de rocas Santonienses que muestran una sucesión de margas neríticas y calizas someras, localmente con calcarenitas arenosas y que terminan con margas de profundidad. Los cambios laterales de facies son evidentes. Los requiénidos, monopleuridos, caprotínidos, radiolítidos, hippurítidos y plagioptychidos son abundantes en esta sucesión, pero se han notado importantes diferencias en la composición de las asociaciones de rudistas, incluso en la morfología de una sola especie, entre las diferentes facies. Los radiolítidos, hippurítidos y plagioptychidos son los rudistas más abundantes y diversificados en la localidad, además de tener los caracteres morfológicos más complejos. Por esta razón, ellos merecían un profundo tratamiento de paleontología sistemática que incluyera una exhaustiva descripción de todas las características de su concha, su variabilidad intraespecífica y su revisión taxonómica. Las siguientes especies han resultado bien caracterizadas: Radiolites angeiodes Lamarck, R. squamosus d´Orbigny, R. vallispetrosae Astre, Biradiolites acuticostatus (d´Orbigny), B. angulosissimus Toucas, B. beaussetensis Toucas, B. canaliculatus d´Orbigny, B. carezi Toucas, Bournonia excavata (d´Orbigny), Praeradiolites plicatus (Lajard, Négrel y Toulouzan), P. toucasi (d´Orbigny), y Sphaerulites caderensis (Toucas) entre los radiolítidos, Hippurites matheroni Douvillé, H. microstylus Douvillé, H. praecessor Douvillé, H. socialis Douvillé, H. sublaevis Matheron, Hippuritella maestrei (Vidal), H. toucasi (d´Orbigny), Vaccinites beaussetensis Toucas, V. galloprovincialis (Matheron), V. giganteus major Toucas, y V. zurcheri (Douvillé) entre los hippurítidos, y Plagioptychus aguilloni (d´Orbigny) y P. toucasi Matheron entre los plagioptychidos. Como consecuencia de este estudio sistemático, la taxonomía de los rudistas del Santoniense inferior pirenaico ha sido fuertemente simplificada y aclarada. El registro y el análisis posterior de las apariciones de las especies de rudistas, y también las diferencias morfológicas en la concha de una misma especie en facies diferentes contribuye a entender la relación entre los parámetros paleoambientales y la composición faunística de las bioconstrucciones de rudistas en el Cretácico superior. / The south Pyrenean locality Collades de Basturs provides extensive and well exposed outcrops of Santonian rocks displaying a succession of shelf marls and shallow-water limestones, with sandy calcarenites locally, and ending with deep-water marls. Lateral changes of facies are evident. Requienid, monopleurid, caprotinid, radiolitid, hippuritid and plagioptychid rudists are abundant there, but important differences are noticed on the composition of the rudist associations, and even the morphology of single species, among the different facies. Radiolitids, hippuritids and plagioptychids are the most abundant and diverse rudists in the locality, besides having the more complex morphological characters. For that reason, they deserved a deep systematic palaeontology treatment including an exhaustive description of all their shell characters and their intraspecific variability, and their taxonomic revision. The following species resulted well characterized: Radiolites angeiodes Lamarck, R. squamosus d´Orbigny, R. vallispetrosae Astre, Biradiolites acuticostatus (d´Orbigny), B. angulosissimus Toucas, B. beaussetensis Toucas, B. canaliculatus d´Orbigny, B. carezi Toucas, Bournonia excavata (d´Orbigny), Praeradiolites plicatus (Lajard, Négrel y Toulouzan), P. toucasi (d´Orbigny), and Sphaerulites caderensis (Toucas) among the radiolitids, Hippurites matheroni Douvillé, H. microstylus Douvillé, H. praecessor Douvillé, H. socialis Douvillé, H. sublaevis Matheron, Hippuritella maestrei (Vidal), H. toucasi (d´Orbigny), Vaccinites beaussetensis Toucas, V. galloprovincialis (Matheron), V. giganteus major Toucas, and V. zurcheri (Douvillé) among the hippuritids, and Plagioptychus aguilloni (d´Orbigny) and P. toucasi Matheron among the plagiopychids. As a consequence of this systematic study, the taxonomy of the lower Santonian Pyrenean rudists became highly simplified and clarified. The record and subsequent analysis of the rudist species occurrences, and also of the different shell morphologies of the same species, in the different facies contributes to the understanding of the relationship between the palaeoenvironmental parameters and the faunal composition in the Late Cretaceous rudist bioconstructions.

Pendent resums