Serge Legendre

Correlation of carnassial tooth size and body weight in recent carnivores (mammalia)

The correlation between the lower carnassial crown area and the body weight is examined for modern carnivores. It is very high, but the ursids and felids show a relationship different from the other carnivore families. Some exceptions are discussed. The possibility of predicting body weight for fossils is given.

Rodents and climate. 1. A model for estimating past temperatures using arvicolids (Mammalia: Rodentia)

Abstract Analysis of 253 extant mammalian local faunas shows that the number of arvicoline species in each fauna is related to temperature parameters. The very high correlation allows us to propose a method to estimate the temperature for fossil faunas bearing arvicoline species from temperate areas. To illustrate this method, mean annual temperatures were estimated for Late Pleistocene Hungarian localities and for a sequence from the Baume de Gigny (Jura, France). These were compared with results obtained by other techniques (multivariate analysis of rodent associations and synthetic analysis of pollen, faunal, and sedimentological data).

Mammalian Communities Document a Latitudinal Environmental Gradient during the Miocene Climatic Optimum in Western Europe

Abstract A total of 17 mammalian communities from south-central Spain to northern Germany spanning the middle Miocene Climatic Optimum (ca. 17–14 Ma) are analyzed. Mammalian body-weight structures (cenograms) are constructed and discussed in terms of paleoenvironmental affinities. They indicate an arid climate and open environments in south-central Spain and closed and densely forested regions with very humid conditions to the north. The data reveal the presence of a strong latitudinal environmental gradient during this period. Other studies based on the fossil records of plants or ectothermic vertebrates showed that virtually no temperature gradient was present in Europe at that time and that mean annual temperatures were very high, probably around 20° C. Mammalian communities, therefore, show the presence of a southwest–northeast aridity-humidity gradient and confirm recent findings based on air-breathing fish distribution and pollen spectra. Atmospheric circulations could be responsible for this meridional gradient, but other regional causes cannot be ruled out. This study indicates that mammal body weight distributions are excellent proxies to investigate the environmental and climatic evolution and compare well with other paleoenvironmental proxies.

The use of MSR (Minimum Sample Richness) for sample assemblage comparisons

Abstract Minimum Sample Richness (MSR) is defined as the smallest number of taxa that must be recorded in a sample to achieve a given level of inter-assemblage classification accuracy. MSR is calculated from known or estimated richness and taxonomic similarity. Here we test MSR for strengths and weaknesses by using 167 published mammalian local faunas from the Paleogene and early Neogene of the Quercy and Limagne area (Massif Central, southwestern France), and then apply MSR to 84 Oligo-Miocene faunas from Riversleigh, northwestern Queensland, Australia. In many cases, MSR is able to detect the assemblages in the data set that are potentially too incomplete to be used in a similarity-based comparative taxonomic analysis. The results show that the use of MSR significantly improves the quality of the clustering of fossil assemblages. We conclude that this method can screen sample assemblages that are not representative of their underlying original living communities. Ultimately, it can be used to identify which assemblages require further sampling before being included in a comparative analysis.

Hipposideridae (Mammalia: Chiroptera) from the Mediterranean middle and late Neogene, and evolution of the genera Hipposideros and Asellia

ABSTRACT New fossils from the Burdigalian locality of Port-la-Nouvelle (southern France) add to our knowledge of the Hipposideridae. Four species of this family are represented, including a new species of the subgenus Brachipposideros Sige Hipposideros aguilari n.sp.). H. vetus (Lavocat) from Beni Mellal (Miocene of Morocco) and H. cf. vetus from Sete (late Pliocene of France), formerly attributed to Asellia, are placed in the subgenus Syndesmotis Peters, which includes the Recent East African species H. (S.) megalotis. The following genera and subgenera are recognized in this study: genus Hipposideros including the subgenera Hipposideros, Brachipposideros, Syndesmotis and Pseu-dorhinolophus, and the genus Asellia. Anatomy of teeth and jaws suggests new phyletic interpretations: Pseudorhinolophus could be ancestral to Asellia, and Brachipposideros to Syndesmotis; Pseudorhinolophus and Brachipposideros may both be represented in the Recent fauna by large and small Hipposideros, respectively; on the other h...

Isotopic and anatomical evidence of an herbivorous diet in the Early Tertiary giant bird Gastornis. Implications for the structure of Paleocene terrestrial ecosystems

The mode of life of the early Tertiary giant bird Gastornis has long been a matter of controversy. Although it has often been reconstructed as an apex predator feeding on small mammals, according to other interpretations, it was in fact a large herbivore. To determine the diet of this bird, we analyze here the carbon isotope composition of the bone apatite from Gastornis and contemporaneous herbivorous mammals. Based on 13C-enrichment measured between carbonate and diet of carnivorous and herbivorous modern birds, the carbonate δ13C values of Gastornis bone remains, recovered from four Paleocene and Eocene French localities, indicate that this bird fed on plants. This is confirmed by a morphofunctional study showing that the reconstructed jaw musculature of Gastornis was similar to that of living herbivorous birds and unlike that of carnivorous forms. The herbivorous Gastornis was the largest terrestrial tetrapod in the Paleocene biota of Europe, unlike the situation in North America and Asia, where Gastornis is first recorded in the early Eocene, and the largest Paleocene animals were herbivorous mammals. The structure of the Paleocene terrestrial ecosystems of Europe may have been similar to that of some large islands, notably Madagascar, prior to the arrival of humans.

Finding the Minimum Sample Richness (MSR) for multivariate analyses: implications for palaeoecology

Many techniques have been developed to estimate species richness and beta diversity. Those techniques, dependent on sampling, require abundance or presence/absence data. Palaeontological data is by nature incomplete, and presence/absence data is often the only type of data that can be used to provide an estimate of ancient biodiversity. We used a simulation approach to investigate the behaviour of commonly used similarity indices, and the reliability of classifications derived from these indices, when working with incomplete data. We drew samples, of varying number and richness, from artificial species lists, which represented original life assemblages, and calculated error rates for classifications of the parent lists and samples. Using these results, we estimated the Minimum Sample Richness (MSR) needed to achieve 95% classification accuracy. Results were compared for classifications derived from several commonly used similarity indexes (Dice, Jaccard, Simpson and Raup–Crick). MSR was similar for the Dice, Jaccard and Simpson indices. MSR for the Raup–Crick index was often much lower, suggesting that it is preferable for classifying patchy data, however the performance of this index was less stable than the other three in the simulations, which required an even lower MSR. MSR can be found for all presence/absence data from the contour graphs and equations as long as the absolute species richness and the beta diversity can be estimated.

Miocene fossil vertebrates from the Nong Hen-I(A) exploration well of Thai Shell Exploration and Production Company Limited, Phitsanulok Basin, Thailand

ABSTRACT The first early to middle Miocene terrestrial mammalian fauna from Thailand (the Nong Hen Local Fauna) was recovered at a depth between 887 and 894 meters in the Thai Shell Exploration and Production Company Ltd. Nong Hen-I(A) well located in the northern part of the country. More than 100 mammalian jaws and teeth were recovered. Most specimens were from a single new species of bat, Mormopterus (Hydromops) nonghenensis but two other bats were also present as well as a small rodent and some other, larger mammal. The preponderance of bats in this assemblage is concordant with its having been recovered from a karst deposit. The stage of evolution of M. (H.) nonghenensis suggests that the Nong Hen Local Fauna is late early to middle Miocene in age.

Evidence of northern Turolian savanna-woodland from the Dorn-Dürkheim 1 fauna (Germany)

Western European Turolian mammalian faunas and palaeoenvironments are less well known than middle and early late Miocene ones for which more data exist at a time when major climate events occurred (Middle Miocene Climatic Optimum followed by Late Middle Miocene Climatic Cooling). In this respect, rich faunas represent exceptional windows into mammalian diversity and biogeography. They constitute key points to understand local palaeoenvironments and refine larger-scale patterns. Dorn-Dürkheim 1 is one of the richest mammalian faunas of Western Europe with at least 79 species of mammals. We investigate this fauna and compare its composition to the faunal and biogeographic context of the European late Miocene. A community-based analysis of body masses of the constituent species together with an original approach on predator–prey biomasses are also attempted to reconstruct its palaeoenvironment. While its composition reflects the known late Miocene context and fits in the biogeographic North–South pattern evidenced by earlier studies, the reconstructed landscape is different from previous hypotheses of densely forested habitats. Our results suggest the presence of a savanna-woodland biome more open than previously thought, in a subtropical-like and seasonal climate. Other palaeoecological studies on elements of the large mammal fauna confirm this interpretation.

Biotic systems and diversity—Report of working group 4, interlaken workshop for past global changes

1 Department of Biology, University of Pennsylvania, Philadelphia, PA 19104 (U.SA.) 2 UA 720 du CNRS, Laboratoire de PaMontologie, Universite de Paris VI, 4, Place Jussieu, F·75252 Paris Cedex 05 (France) 3 Department of Geological Sciences, The University of Binningham, P.O. Box 363, Binningham B15 217 (U.K.) 4 Geologisches Institut, Eidgenassische Technische Hochschule, CH·8092 Zurich (Switzerland) Il Department of Geophysical Sciences, University of Chicago, 5734 Ellis Avenue, Chicago, IL 60637 (U.SA.) 6 Department of Geological Sciences, University of Colorado, Boulder, CO 80309 (U.SA.) 7 Laboratoire de PaMontologie, Universite de Montpellier, F·34060 MontpeUier (France) 8 Department of Geosciences, University of Arizona, Tucson, AZ 85721 (U.SAJ 9 Geological Suroey of Canada, Room 292,601 Booth Street, Ottawa, Onto KIA OEB (Canada) 10 Upper Meadow, Old Road, Hedington, Oxford OX3 8SZ (U.K.) 11 Department of Geosciences, Pennsylvania State University, 435 Deike Building, University Park, PA 16802 (U.8AJ