Background: Fieldwork has thoroughly established that most eggs are intensely predated. Among the few exceptions are the aerial egg clutches from the aquatic snail Pomacea canaliculata which have virtually no predators. Its defenses are advertised by the pigmented ovorubin perivitellin…

Me propongo analizar y discutir algunos resultados de una investigación etnográfica desarrollada en comunidades Mbya Guaraníes (Misiones, Argentina) acerca de las representaciones y prácticas relacionadas con la crianza y el desarrollo infantil.
En este trabajo caracterizo las categorías, representaciones y…

Tardigrades constitute one of three clades of Xenarthra. Whereas modern tree sloths are common in the Amazonian Basin, their giant ground sloth "kin" were abundant throughout the Americas. During the Miocene, sloths were conspicuous faunal elements in Patagonia, generally considered…

Recent contributions to the knowledge of Gondwanan cynodonts highlight the presence in Africa of taxa previously recognized in South America and vice-versa. This is the case for the Middle Triassic Namibian fauna from the upper Omingonde Formation, where the first…

Talampaya and Tarjados Formations correspond to the initial stage of the Ischigualasto-Villa Unión Basin filling, and record the oldest post-Permian events in the region. The sequence consists of red beds deposited essentially by ephemeral alluvial and fluvial systems, and overlay…

Lakes are excellent sensors of environmental change, including climate change. Chironomids (Insecta, Diptera) and ostracods (Crustacea) are among the most useful biological indicators for paleoenvironmental reconstruction found in lake sediments, due to their sensitiveness to environmental variables. However, the use…

During the last years the knowledge about derived eusuchian crocodiles has been increased. Anatomical and phylogenetic approaches as well as new fossil records have lighted the evolutive and biogeographic history of several groups. In this way, paleontological research on Miocene-Pliocene…

The glacigenic boulders from the Hirnantian Don Braulio Formation of the Argentine Precordillera contain a well preserved shelly fauna allowing to a better knowledge of brachiopods and bivalves, but gastropods remain undescribed. The purpose of this paper is to give…

Although South America lost more megafaunal genera than any other continent during the Late-Quaternary Extinction event (LQE), little is known about the chronology, causes or dynamics of these extinctions, especially in the northern part of the continent. Fossil deposits in…

The Paleontology teams at the Universidade Federal do Acre (UFAC) and the Universidade de Brasília (UnB) worked together in order to increase macro and micropaleontological knowledge of the late Miocene rocks exposed at Niterói (10º08'30''S-67º48'46,3''W), on the right margin of…