Your browser doesn't support javascript.
loading
Montrer: 20 | 50 | 100
Résultats 1 - 16 de 16
Filtrer
Plus de filtres










Base de données
Gamme d'année
1.
Zoology (Jena) ; 148: 125946, 2021 10.
Article de Anglais | MEDLINE | ID: mdl-34388442

RÉSUMÉ

Pioneering fieldwork identified the existence of three feeding groups in vultures: gulpers, rippers and scrappers. Gulpers engulf soft tissue from carcasses and rippers tear off pieces of tough tissue (skin, tendons, muscle), whereas scrappers peck on small pieces of meat they find on and around carcasses. It has been shown that these feeding preferences are reflected in the anatomy of the skull and neck. Here, we demonstrate that these three feeding groups also emerge when body core and limb bones are added to the analysis. However, the resulting classification differs from that which is based on skull morphology for three species, namely Gypaetus barbatus (Linnaeus, 1758), Gypohierax angolensis (Gmelin, 1788) and Gyps indicus (Scopoli, 1786). The proposed classification would improve the interrelationship between form and feeding habits in vultures. Moreover, the results of this study reinforce the value of the categorisation system introduced by Kruuk (1967), and expanded by König (1974, 1983), Houston (1988) and Hertel (1994), as it would affect not only the skull morphology but the whole-body architecture.


Sujet(s)
Falconiformes/anatomie et histologie , Falconiformes/physiologie , Comportement alimentaire/physiologie , Crâne/anatomie et histologie , Animaux , Falconiformes/classification
2.
Proc Biol Sci ; 287(1938): 20202085, 2020 11 11.
Article de Anglais | MEDLINE | ID: mdl-33143584

RÉSUMÉ

Insular gigantism-evolutionary increases in body size from small-bodied mainland ancestors-is a conceptually significant, but poorly studied, evolutionary phenomenon. Gigantism is widespread on Mediterranean islands, particularly among fossil and extant dormice. These include an extant giant population of Eliomys quercinus on Formentera, the giant Balearic genus †Hypnomys and the exceptionally large †Leithia melitensis of Pleistocene Sicily. We quantified patterns of cranial and mandibular shape and their relationships to head size (allometry) among mainland and insular dormouse populations, asking to what extent the morphology of island giants is explained by allometry. We find that gigantism in dormice is not simply an extrapolation of the allometric trajectory of their mainland relatives. Instead, a large portion of their distinctive cranial and mandibular morphology resulted from the population- or species-specific evolutionary shape changes. Our findings suggest that body size increases in insular giant dormice were accompanied by the evolutionary divergence of feeding adaptations. This complements other evidence of ecological divergence in these taxa, which span predominantly faunivorous to herbivorous diets. Our findings suggest that insular gigantism involves context-dependent phenotypic modifications, underscoring the highly distinctive nature of island faunas.


Sujet(s)
Évolution biologique , Myoxidae/physiologie , Adaptation physiologique , Animaux , Mensurations corporelles , Fossiles
3.
Parasitol Int ; 66(2): 7-11, 2017 Apr.
Article de Anglais | MEDLINE | ID: mdl-27871871

RÉSUMÉ

Myotragus balearicus (Artiodactyla, Caprinae) is an extinct caprine endemic of the Eastern Balearic Islands or Gymnesics (i.e., Mallorca, Menorca and surrounding islets, Western Mediterranean Sea). In spite of its small size, c. 50cm height at the shoulder, it was the largest mammal inhabiting these islands until the human arrival, and it had peculiar short legs and frontal vision. It disappeared between 2830 and 2210calBCE. The coprolites here studied were recovered from Cova Estreta, in Pollença, Mallorca. The samples were subjected to microscopic examination and enzyme-linked immunosorbent assays (ELISA) for E. histolytica/E. dispar, Giardia intestinalis and Cryptosporidium parvum. This study provides new paleoparasitological data from an extinct animal species of the Holocene period. The microscopy revealed one sample containing uninucleated-cyst of Entamoeba sp., whereas ELISA detected nine positive samples for Cryptosporidium sp. The finding of these protozoans can help in the discussion of its extinction cause and demonstrates the antiquity and the evolutionary history of host-parasite relationships between protozoa and caprines since the Messinian.


Sujet(s)
Fèces/parasitologie , Fossiles/parasitologie , Ruminants/parasitologie , Animaux , Évolution biologique , Cryptosporidium parvum/immunologie , Cryptosporidium parvum/isolement et purification , Cryptosporidium parvum/ultrastructure , Entamoeba/immunologie , Entamoeba/isolement et purification , Entamoeba/ultrastructure , Test ELISA , Extinction biologique , Giardia lamblia/immunologie , Giardia lamblia/isolement et purification , Giardia lamblia/ultrastructure , Interactions hôte-parasite , Humains , Iles de la Méditerranée , Phylogenèse , Espagne
4.
Zootaxa ; 4085(1): 141-2, 2016 Mar 01.
Article de Anglais | MEDLINE | ID: mdl-27394294

RÉSUMÉ

In a recent paper, we described five new species of rails from the Macaronesian islands (Alcover et al., 2015). We proposed the name of Rallus minutus to designate the São Jorge rail. One day after its publication, Fred Ruhe (via e-mail) pointed out to us that the name was preoccupied, making Rallus minutus Alcover, Pieper, Pereira & Rando 2015 a primary homonym, which in turn makes it permanently invalid.


Sujet(s)
Oiseaux/classification , Animaux , Iles , Terminologie comme sujet
5.
Zootaxa ; 4057(2): 151-90, 2015 Dec 10.
Article de Anglais | MEDLINE | ID: mdl-26701473

RÉSUMÉ

Five new species of recently extinct rails from two Macaronesian archipelagoes (Madeira and Azores) are described. All the species are smaller in size than their presumed ancestor, the European rail Rallus aquaticus. Two species inhabited the Madeira archipelago: (1) Rallus lowei n. sp., the stouter of the species described herein, was a flightless rail with a robust tarsometatarsus and reduced wings that lived on Madeira Island; (2) Rallus adolfocaesaris n. sp., a flightless and more gracile species than its Madeiran counterpart, inhabited Porto Santo. So far, six Azorean islands have been paleontologically explored, and the remains of fossil rails have been found on all of them. Here we formally describe the best-preserved remains from three islands (Pico, São Miguel and São Jorge): (1) Rallus montivagorum n. sp., a rail smaller than R. aquaticus with a somewhat reduced flying capability, inhabited Pico; (2) Rallus carvaoensis n. sp., a small flightless rail with short and stout legs and a bill apparently more curved than in R. aquaticus, was restricted to São Miguel; (3) Rallus minutus n. sp., a very small (approaching Atlantisia rogersi in size) flightless rail with a shortened robust tarsometatarsus, lived in São Jorge. We note also the presence of rail fossils on three other Azorean islands (Terceira, Graciosa and Santa Maria). In addition, we describe an extraordinarily complete fossil of an unnamed Rallus preserved in silica from the locality of Algar do Carvão on Terceira.


Sujet(s)
Oiseaux/classification , Répartition des animaux , Structures anatomiques de l'animal/anatomie et histologie , Structures anatomiques de l'animal/croissance et développement , Animaux , Océan Atlantique , Oiseaux/anatomie et histologie , Oiseaux/croissance et développement , Mensurations corporelles , Extinction biologique , Femelle , Iles , Mâle , Taille d'organe
6.
Integr Zool ; 9(2): 183-196, 2014 Mar.
Article de Anglais | MEDLINE | ID: mdl-24673762

RÉSUMÉ

The vertebrate fossil record from the Balearic Islands (western Mediterranean) has improved considerably over the past decade, especially in Mallorca and Menorca. In Menorca, the Pliocene terrestrial fauna was updated by the discovery and description of the large-sized leporid Nuralagus, several reptiles and an amphibian. In Mallorca, paleontological exploration yielded 2 deposits with a Late Miocene/Early Pliocene chronology, Caló den Rafelino (CdR) and Na Burguesa-1 (NB-1). So far, 4 new mammalian taxa and 2 new reptiles have been identified for the CdR deposit, whereas the faunal assemblage from the recently discovered deposit (Apr 2012) of NB-1 is currently composed of, at least, 6 terrestrial mammals, 8 reptiles and an amphibian. Its faunal composition and some primitive characteristics of the obtained taxa suggest that the chronology of this deposit is slightly earlier than the CdR. The terrestrial vertebrates recorded in these 2 Mallorcan deposits are changing the view of the paleofaunal assemblage previously known for the Plio-Pleistocene of the island. Morphological characteristics displayed by some of the taxa suggest that these faunas would be at the beginning of an isolated evolution. In this paper we present a preliminary report on the fossils recovered from the NB-1 deposit, as well as some unpublished data from CdR, and we analyze the whole fauna from both Mallorcan deposits, focusing on taxonomical and paleobiogeographical aspects.


Sujet(s)
Évolution biologique , Fossiles , Phylogenèse , Vertébrés/anatomie et histologie , Animaux , Os et tissu osseux/anatomie et histologie , Iles de la Méditerranée , Paléontologie/méthodes , Phylogéographie , Spécificité d'espèce , Vertébrés/classification
7.
Proc Biol Sci ; 281(1780): 20133126, 2014 Apr 07.
Article de Anglais | MEDLINE | ID: mdl-24523273

RÉSUMÉ

Owing to the catastrophic extinction events that occurred following the Holocene arrival of alien species, extant oceanic island biotas are a mixture of recently incorporated alien fauna and remnants of the original fauna. Knowledge of the Late Quaternary pristine island faunas and a reliable chronology of the earliest presence of alien species on each archipelago are critical in understanding the magnitude and tempo of Quaternary island extinctions. Until now, two successive waves of human arrivals have been identified in the North Atlantic Macaronesian archipelagos (Azores, Madeira, Selvagens, Canary and Cape Verde Islands): 'aboriginal', which is limited to the Canary Islands around two millennia ago, and 'colonial', from the fourteenth century onwards. New surveys in Ponta de São Lourenço (Madeira Island) have allowed us to obtain and date ancient bones of mice. The date obtained (1033 ± 28 BP) documents the earliest evidence for the presence of mice on the island. This date extends the time frame in which the most significant ecological changes occurred on the island. It also suggests that humans could have reached Madeira before 1036 cal AD, around four centuries before Portugal officially took possession of the island.


Sujet(s)
Fossiles , Souris/physiologie , Animaux , Biodiversité , Humains , Densité de population , Portugal , Datation radiométrique
8.
PLoS One ; 8(7): e70743, 2013.
Article de Anglais | MEDLINE | ID: mdl-23936247

RÉSUMÉ

In mammals that grow up more slowly and live longer, replacement teeth tend to appear earlier in sequence than in fast growing mammals. This trend, known as 'Schultz's Rule', is a useful tool for inferring life histories of fossil taxa. Deviations from this rule, however, suggest that in addition to the pace of life history, ecological factors may also drive dental ontogeny. Myotragus balearicus is an extinct insular caprine that has been proved to be an excellent test case to correlate morphological traits with life history. Here we show that Myotragus balearicus exhibits a slow signature of dental eruption sequence that is in agreement with the exceptionally slow life history of this species, thus conforming to 'Schultz's Rule'. However, our results also show an acceleration of the absolute pace of development of the permanent incisors in relation to that of the posterior teeth. The rodent-like incisors of Myotragus balearicus erupted early not only in relative but also in absolute terms (chronological age), suggesting that feeding characteristics also plays an important role in dental ontogeny. This is in agreement with ecological hypotheses based on primates. Our study documents a decoupling of the pace of development of teeth in mammals that is triggered by different selection pressures on dental ontogeny. Moreover, we show that Myotragus kopperi from the early Pleistocene (a direct ancestor of the late Pleistocene-Holocene M. balearicus) follows the pattern of first incisor replacement known in living bovids. Hence, the advance in the eruption sequence of the first incisors occurs along the Myotragus evolutionary lineage over a period of about 2.5 Myr. To our knowledge, this is the first fossil evidence of an advance of the emergence of the permanent first incisor along an anagenetic mammalian lineage.


Sujet(s)
Extinction biologique , Fossiles , Capra/physiologie , Incisive/anatomie et histologie , Mandibule/anatomie et histologie , Animaux , Évolution biologique , Comportement alimentaire , Capra/anatomie et histologie , Incisive/physiologie , Mammifères , Mandibule/physiologie , Phylogenèse , Facteurs temps , Éruption dentaire
9.
Zootaxa ; 3647: 343-57, 2013.
Article de Anglais | MEDLINE | ID: mdl-26295111

RÉSUMÉ

The extinct São Miguel Scops Owl Otusfrutuosoi n. sp. is described from fossil bones found in Gruta de Água de Pau, a volcanic tube in São Miguel Island (Azores Archipelago, North Atlantic Ocean). It is the first extinct bird described from the Azores and, after the Madeiran Scops Owl (O. mauli Rando, Pieper, Alcover & Olson 2012a), the second extinct species of Strigiformes known in Macaronesia. The forelimb elements of the new taxon are shorter, the hindlimb elements are longer, and the pelvis is shorter and broader than in the Eurasian Scops Owl (O. scops Linnaeus). The new species differs from O. mauli in the smaller size of many of its bones, especially the ulna and tibiotarsus. Its measurements (estimated weight, wing area, and wing loading, and the ratio of humerus + ulna + carpometacarpus length/femur length) indicate weak powers of flight and ground-dwelling habits. The latest occurrence of the new species, as evidenced by a radiocarbon date of 1970 ± 40 BP from bone collagen, indicates a Late Holocene extinction event subsequent to 49 cal BC, and was probably linked to human arrival and subsequent habitat alterations.


Sujet(s)
Extinction biologique , Strigiformes/anatomie et histologie , Strigiformes/classification , Répartition des animaux , Animaux , Açores , Spécificité d'espèce , Strigiformes/physiologie
10.
PLoS One ; 7(2): e31123, 2012.
Article de Anglais | MEDLINE | ID: mdl-22363563

RÉSUMÉ

BACKGROUND: The lava mouse, Malpaisomys insularis, was endemic to the Eastern Canary islands and became extinct at the beginning of the 14(th) century when the Europeans reached the archipelago. Studies to determine Malpaisomys' phylogenetic affinities, based on morphological characters, remained inconclusive because morphological changes experienced by this insular rodent make phylogenetic investigations a real challenge. Over 20 years since its first description, Malpaisomys' phylogenetic position remains enigmatic. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we resolved this issue using molecular characters. Mitochondrial and nuclear markers were successfully amplified from subfossils of three lava mouse samples. Molecular phylogenetic reconstructions revealed, without any ambiguity, unsuspected relationships between Malpaisomys and extant mice (genus Mus, Murinae). Moreover, through molecular dating we estimated the origin of the Malpaisomys/mouse clade at 6.9 Ma, corresponding to the maximal age at which the archipelago was colonised by the Malpaisomys ancestor via natural rafting. CONCLUSION/SIGNIFICANCE: This study reconsiders the derived morphological characters of Malpaisomys in light of this unexpected molecular finding. To reconcile molecular and morphological data, we propose to consider Malpaisomys insularis as an insular lineage of mouse.


Sujet(s)
Extinction biologique , Souris/génétique , Paléontologie , Phylogenèse , Rodentia/génétique , Animaux , Artéfacts , Évolution biologique , ADN/génétique , Fossiles , Géographie , Fonctions de vraisemblance , Données de séquences moléculaires , Mutation/génétique , Réaction de polymérisation en chaîne , Analyse de séquence d'ADN , Espagne , Facteurs temps , Dent/anatomie et histologie
11.
Naturwissenschaften ; 98(1): 33-7, 2011 Jan.
Article de Anglais | MEDLINE | ID: mdl-21107517

RÉSUMÉ

Malpaisomys insularis is a mouse-like rodent endemic to the eastern Canary Islands. It became extinct during the fourteenth century. It was a remarkable species living under hyperarid conditions. A dental microwear analysis was performed in order to determine its former diet. The elevated number of fine scratches found in Malpaisomys molars suggests that it consumed a significant part of Poaceae, grass consumption leaving the most distinctive features on dental wear facets. A graminivorous diet with a high amount of abrasive items is in agreement with the broad teeth of Malpaisomys, considered as adapted to grass consumption. However, in the absence of potential competitors over its native range, it is likely that Malpaisomys also foraged on dicots to meet higher nutrient and energetic requirements. The ecology of Malpaisomys is discussed from these results in the context of the desertic climatic conditions of the eastern Canary Islands and with a special concern on its small body size in contrast to other large-sized island murine species such as the giant rats of the central Canary Islands.


Sujet(s)
Régime alimentaire , Fossiles , Souris/anatomie et histologie , Souris/physiologie , Dent/anatomie et histologie , Animaux , Analyse discriminante , Espagne
12.
PLoS One ; 5(9): e12956, 2010 Sep 23.
Article de Anglais | MEDLINE | ID: mdl-20886036

RÉSUMÉ

BACKGROUND: Evolutionary studies of insular biotas are based mainly on extant taxa, although such biotas represent artificial subsets of original faunas because of human-caused extinctions of indigenous species augmented by introduced exotic taxa. This makes it difficult to obtain a full understanding of the history of ecological interactions between extant sympatric species. Morphological bill variation of Fringilla coelebs and F. teydea (common and blue chaffinches) has been previously studied in the North Atlantic Macaronesian archipelagos. Character displacement between both species has been argued to explain bill sizes in sympatry. However, this explanation is incomplete, as similar patterns of bill size have been recorded in F. coelebs populations from islands with and without F. teydea. METHODOLOGY/PRINCIPAL FINDINGS: The discovery of a new extinct species in Tenerife (Canary Islands), here named Carduelis aurelioi n. sp. (slender-billed greenfinch), provides the opportunity to study ancient ecological interactions among Macaronesian finches. To help understand the evolutionary histories of forest granivores in space and time, we have performed a multidisciplinary study combining: (1) morphological analyses and radiocarbon dating (11,460±60 yr BP) of the new taxon and, (2) molecular divergence among the extant finch species and populations in order to infer colonization times (1.99 and 1.09 My for F. teydea and F. coelebs respectively). CONCLUSION/SIGNIFICANCE: C. aurelioi, F. coelebs and F. teydea co-habited in Tenerife for at least one million years. The unique anatomical trends of the new species, namely chaffinch-like beak and modified hind and forelimbs, reveal that there was a process of divergence of resource competition traits among the three sympatric finches. The results of our study, combined with the presence of more extinct greenfinches in other Macaronesian islands with significant variation in their beak sizes, suggests that the character displacement has influenced patterns of divergence in bill size and shape on other Macaronesian islands as well.


Sujet(s)
Espèce en voie de disparition , Fringillidae/génétique , Paléontologie , Animaux , Évolution biologique , Fringillidae/classification , Géographie , Phylogenèse , Espagne
13.
PLoS One ; 5(12): e16072, 2010 Dec 31.
Article de Anglais | MEDLINE | ID: mdl-21209838

RÉSUMÉ

BACKGROUND: The loss of species during the Holocene was, dramatically more important on islands than on continents. Seabirds from islands are very vulnerable to human-induced alterations such as habitat destruction, hunting and exotic predators. For example, in the genus Puffinus (family Procellariidae) the extinction of at least five species has been recorded during the Holocene, two of them coming from the Canary Islands. METHODOLOGY/PRINCIPAL FINDINGS: We used bones of the two extinct Canary shearwaters (P. olsoni and P. holeae) to obtain genetic data, for use in providing insights into the differentiation process within the genus Puffinus. Although mitochondrial DNA (mtDNA) cytochrome b sequences were successfully retrieved from four Holocene specimens of the extinct Lava shearwater (P. olsoni) from Fuerteventura (Canary Islands), the P. holeae specimens yielded no DNA. Only one haplotype was detected in P. olsoni, suggesting a low genetic diversity within this species. CONCLUSIONS: The phylogenetic analyses based on the DNA data reveal that: (i) the "Puffinus puffinus complex", an assemblage of species defined using osteological characteristics (P. puffinus, P. olsoni, P. mauretanicus, P. yelkouan and probably P. holeae), shows unresolved phylogenetic relationships; (ii) despite the differences in body size and proportions, P. olsoni and the extant P. puffinus are sister species. Several hypotheses can be considered to explain the incipient differentiation between P. olsoni and P. puffinus.


Sujet(s)
Oiseaux/génétique , Oiseaux/physiologie , ADN mitochondrial/génétique , ADN/génétique , Extinction biologique , Animaux , Évolution biologique , Os et tissu osseux/anatomopathologie , Écosystème , Variation génétique , Géographie , Haplotypes , Histoire ancienne , Mitochondries/métabolisme , Modèles génétiques , Phylogenèse , Comportement prédateur , Espagne
14.
PLoS One ; 4(5): e5670, 2009 May 22.
Article de Anglais | MEDLINE | ID: mdl-19461892

RÉSUMÉ

BACKGROUND: Numerous endemic mammals, including dwarf elephants, goats, hippos and deers, evolved in isolation in the Mediterranean islands during the Pliocene and Pleistocene. Most of them subsequently became extinct during the Holocene. Recently developed high-throughput sequencing technologies could provide a unique tool for retrieving genomic data from these extinct species, making it possible to study their evolutionary history and the genetic bases underlying their particular, sometimes unique, adaptations. METHODOLOGY/PRINCIPALS FINDINGS: A DNA extraction of a approximately 6,000 year-old bone sample from an extinct caprine (Myotragus balearicus) from the Balearic Islands in the Western Mediterranean, has been subjected to shotgun sequencing with the GS FLX 454 platform. Only 0.27% of the resulting sequences, identified from alignments with the cow genome and comprising 15,832 nucleotides, with an average length of 60 nucleotides, proved to be endogenous. CONCLUSIONS: A phylogenetic tree generated with Myotragus sequences and those from other artiodactyls displays an identical topology to that generated from mitochondrial DNA data. Despite being in an unfavourable thermal environment, which explains the low yield of endogenous sequences, our study demonstrates that it is possible to obtain genomic data from extinct species from temperate regions.


Sujet(s)
Climat , Extinction biologique , Génomique , Capra/génétique , Paléontologie/méthodes , Analyse de séquence d'ADN/méthodes , Substitution d'acide aminé , Animaux , Appariement de bases , Génome/génétique , Fonctions de vraisemblance , Iles de la Méditerranée , Phylogenèse , Espagne
15.
BMC Evol Biol ; 5: 70, 2005 Dec 06.
Article de Anglais | MEDLINE | ID: mdl-16332256

RÉSUMÉ

BACKGROUND: Myotragus balearicus was an endemic bovid from the Balearic Islands (Western Mediterranean) that became extinct around 6,000-4,000 years ago. The Myotragus evolutionary lineage became isolated in the islands most probably at the end of the Messinian crisis, when the desiccation of the Mediterranean ended, in a geological date established at 5.35 Mya. Thus, the sequences of Myotragus could be very valuable for calibrating the mammalian mitochondrial DNA clock and, in particular, the tree of the Caprinae subfamily, to which Myotragus belongs. RESULTS: We have retrieved the complete mitochondrial cytochrome b gene (1,143 base pairs), plus fragments of the mitochondrial 12S gene and the nuclear 28S rDNA multi-copy gene from a well preserved Myotragus subfossil bone. The best resolved phylogenetic trees, obtained with the cytochrome b gene, placed Myotragus in a position basal to the Ovis group. Using the calibration provided by the isolation of Balearic Islands, we calculated that the initial radiation of caprines can be dated at 6.2 +/- 0.4 Mya. In addition, alpine and southern chamois, considered until recently the same species, split around 1.6 +/- 0.3 Mya, indicating that the two chamois species have been separated much longer than previously thought. CONCLUSION: Since there are almost no extant endemic mammals in Mediterranean islands, the sequence of the extinct Balearic endemic Myotragus has been crucial for allowing us to use the Messinian crisis calibration point for dating the caprines phylogenetic tree.


Sujet(s)
Évolution moléculaire , Capra/génétique , Mammifères/génétique , Ruminants/génétique , Animaux , Évolution biologique , Clonage moléculaire , Cytochromes b/génétique , ADN mitochondrial/composition chimique , ADN ribosomique/composition chimique , Fossiles , Fonctions de vraisemblance , Phylogenèse , Facteurs temps
16.
Mol Phylogenet Evol ; 25(3): 501-10, 2002 Dec.
Article de Anglais | MEDLINE | ID: mdl-12450754

RÉSUMÉ

Myotragus balearicus was a dwarf artiodactyl endemic to the Eastern Balearic Islands, where it evolved in isolation for more than 5 million years before becoming extinct between 3640 and 2135 cal BC (calibrated years BC). Numerous unusual apomorphies obscure the relationship between Myotragus and the extant Caprinae. Therefore, genetic data for this species would significantly contribute to the clarification of its taxonomic position. In this study, we amplify, sequence, and clone a 338-base pair (bp) segment of the mitochondrial cytochrome b (cyt b) gene from a >9Kyr Myotragus subfossil from la Cova des Gorgs (Mallorca). Our results confirm the phylogenetic affinity of Myotragus with the sheep (Ovis) and the takin (Budorcas). In each tree, the Myotragus branch is long in comparison with the other taxa, which may be evidence of a local change in the rate of evolution in cyt b. This rate change may be due to in part to an early age of first reproduction and short generation time in Myotragus, factors that are potentially related to the extreme reduction in size of the adult Myotragus as compared to the other Caprinae.


Sujet(s)
Bovins/classification , Bovins/génétique , Animaux , Séquence nucléotidique , Évolution biologique , Clonage moléculaire , Cytochromes de type b/génétique , ADN mitochondrial , Évolution moléculaire , Extinction (psychologie) , Données de séquences moléculaires , Phylogenèse , Analyse de séquence d'ADN , Similitude de séquences d'acides nucléiques , Facteurs temps
SÉLECTION CITATIONS
DÉTAIL DE RECHERCHE
...