Influence of phylogeny on the estimation of diet from dental morphology in the Carnivora

Because teeth are the most easily preserved part of the vertebrate skeleton and are particularly morphologically variable in mammals, studies of fossil mammals rely heavily on dental morphology. Dental morphology is used both for systematics and phylogeny as well as for inferences about paleoecology, diet in particular. We analyze the influence of evolutionary history on our ability to reconstruct diet from dental morphology in the mammalian order Carnivora, and we find that much of our understanding of diet in carnivorans is dependent on the phylogenetic constraints on diet in this clade. Substantial error in estimating diet from dental morphology is present regardless of the morphological data used to make the inference, although more extensive morphological datasets are more accurate in predicting diet than more limited character sets. Unfortunately, including phylogeny in making dietary inferences actually decreases the accuracy of these predictions, showing that dietary predictions from morphology are substantially dependent on the evolutionary constraints on carnivore diet and tooth shape. The “evolutionary ratchet” that drives lineages of carnivorans to evolve greater degrees of hypercarnivory through time actually plays a role in allowing dietary inference from tooth shape, but consequently requires caution in interpreting dietary inference from the teeth fossil carnivores. These difficulties are another reminder of the differences in evolutionary tempo and mode between morphology and ecology.

Rodents from the Baynunah Formation

The Baynunah Formation of western Abu Dhabi Emirate includes the only record of late Miocene fossil mammals from the Arabian Peninsula. This study reports on new fossil rodents, recording three species previously unknown from the fauna. The first fossil squirrel from the Baynunah Formation is described here, although the limited material makes a detailed taxonomic assessment difficult. An additional indeterminate dendromurine species is also identified. Additionally, a new genus and species of an exceedingly large fossil gerbil, [gen et sp nov], is described. This species exhibits several primitive traits relative to the co-occurring Abudhabia baynunensis, yet is more derived than closely related (yet older) Ameuromys grandis. [gen et sp nov] most likely represents an intermediate species in the Ameuromys grandis — Abudhabia baynunensis group. The rodent fauna also supports previous biochronological estimates for the Baynunah Formation (8 to 6 Ma). The absence of leporids among the Baynunah micromammals suggests the fauna is older than 7 Ma. Lastly, although the Baynunah fauna shows a strong African biogeographic signal overall, the rodents represent a portion of the fauna with significant relationships with Asia.

The Fossil Birds of Peter Lund

The Danish naturalist Peter Wilhelm Lund (1801–1880), regarded as the father of Brazilian palaeontology and archaeology, is known mainly for his work with fossil mammals of Quaternary age from the limestone caves of the Lagoa Santa region in the state of Minas Gerais, southeastern Brazil. However, during one decade of fieldwork (1835–1844), he also collected a large number of remains of other animal groups from these caves. Birds were well represented and, following assessment by the Danish ornithologist Oluf Winge (1855–1889), most of the specimens collected by Lund belong to species still living in the area. Here we present an overview of the bird remains (fossil and recent), found by Lund and others in the region, we update their taxonomic attributions, and comment on the history of the material, making information previously published only in Danish available in English.

MARCAS EM FÓSSEIS DE MEGAFAUNA EM LAGOA DA PEDRA, SALGUEIRO-PE

Este trabalho descreve marcas encontradas em fósseis de mamíferos pleistocênicos do Sítio Lagoa da Pedra, que fica localizado no distrito de Conceição das Creoulas, identificando possíveis relações temporais e/ou físicas entre os grupos pré-históricos e a megafauna que coabitou a região nordeste do Brasil, em Salgueiro - PE, no Pleistoceno Final - Holoceno Inicial. A metodologia aplicada, utilizando microscópio estereoscópico, identificou fósseis que apresentam marcas que foram possivelmente causadas por instrumentos líticos. O trabalho apresenta indícios de interação homem-megafauna através da caça desses animais, reforçando evidências já existentes sobre a coabitação durante o final do Pleistoceno e início do Holoceno.BRANDS ON MEGAFAUNA FOSSILS IN LAGOA DA PEDRA, SALGUEIRO-PE, BRAZIL ABSTRACTThis work describes marks found on fossil mammals of the Pleistocene Lagoa da Pedra Site, which is located in the Conceição das Creoulas district, identifying possible temporal and / or physical relationships between prehistoric groups and the megafauna that cohabitated the northeast region of Brazil. , in Salgueiro - PE, in the Late Pleistocene - Early Holocene. The applied methodology, using stereoscopic microscope, identified fossils presenting marks that were possibly caused by lithic instruments. This work presents evidence of human-megafauna interaction through hunting of these animals, reinforcing existing evidence on cohabitation during the late Pleistocene and early Holocene.Keywords: Quaternary; marks; fossils; pleistocene mammals; megamammals.