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Insular dwarfism and Quaternary Mammals. Insular dwarfism appears to be a general evolution rule for large mammals, as the giantism is for the small ones, but the phenomenon concerns some kind of islands only, and only a small number of Mammalian Families. Necessary conditions for one island to develop such an insular fauna rely on : 1. a not too long way off nor a too reduced one from the nearest continent, peopling occurring through temporary landbrige, by «sweepstake » and/or by natural rafts ; coastal as well as oceanic islands are hence excluded. 2. never a too small nor a too large surface ; very large geographically continental masses such as South America, Australia, New Guinea, Malagasy and other succeeded in developping equilibrated faunas when isolated. 3. a biological imbalance testimonied by the scarcity or the absence of predatorious mammals and by a poor biodiversity ; individuals may be very numerous but the number of mammalian species is always very low, usually well inferior to ten. So the dwarfing (and giantism) process is known for the Quaternary Era only in Mediterranean (Balearic Archipelago, Corsica, Sardinia, Maltese Archipelago, Crete, Cyprus, some Aegean Islands), Arctic Ocean (Wrangel Island), Northern Pacific (Northern Chanel Islands in California), Indonesia (Timor, Flores, Sulawesi), Japan and West Indies. Seven Mammalian families only are involved in dwarfing processes, pertaining to three Orders : Proboscidea (Elephantidae, Stegodontidae) , Artiodactyla (Suidae, Hippopotamidae, Cervidae, Bovidae) and Xenarthra (Megalonychidae) . Among these families, four (Elephantidae, Hippopotamidae, Cervidae and Megalonychidae) are more affected than the other, giving a stature reduction up to one third or one fourth of that of the continental ancestor. Families presenting an insular giantism (some among Rodentia and Insectivora) are limited in number in the same way. Other (all these included in Primates, Carnivora, Lagomorpha) are totally indifferent to any insular environment, and do not show any tendency to reduce nor increase their stature. Lastly, some families (like all the Perissodactyla ones) were never encountered in true insular conditions. The cause of insular dwarfism phenomenon is not well known : the most classical explanation rests in the supposed advantage of smaller individuals requiring less feeding facing a limited quantity of available food together with a lack of predators. Such an explanation is clearly insufficient in many cases, and further research is necessary for a better understanding of the actually observed facts., Guérin Claude. Le nanisme insulaire au Quaternaire. In: Bulletin mensuel de la Société linnéenne de Lyon, 66ᵉ année, n°3, mars 1997. pp. 69-80.

The endemism of the intertropical megafauna in South America in the Pleistocene : giant ground sloths from the Archaeological Area of São Raimundo Nonato (Piaui, Brazil). Among the numerous archaeological sites discovered since 1970 and constituting the São Raimundo Nonato Archaeological Area (North-Eastern Brazil), six were recently found in metamorphized limestones or in a palustrine environment. They yielded thereby an abundant Vertebrate and Invertebrate Upper Pleistocene fossil fauna associated with an Upper Palaeolithic human industry. Four species of giant ground sloths were found : the Mylodontids Scelidotherines Catonyx cuvieri (Lund) and Scelidodon sp., the Megatherid Megatherine Eremotherium lundi (Paula Couto) and the Megalonychid Xenocnine cf. Xenocnus cearensis Paula Couto. Catonyx cuvieri clearly distinguishable from its parent genera Scelidotherium and Scelidodon, is abundant at the Toca da Cima dos Pilão and at the Toca da Janela da Barra do Antonião. It occurs in the sites of Sumidouro do Sansão, Toca do Garrincho et probably too at São Vitor. This species, which was defined by Lund from the Lagoa Santa Caves (Minas Gérais), is a very hypsodont one and was probably feeding on grasses and twigs. It is known exclusively from the Upper Pleistocene levels. Although frequently encountered in Brazilian North East deposits, it seems unknown southern of the Minas Gerais. Many remains of Scelidodon sp. were discovered some months ago in Garrincho, associated with Catonyx, but we are provisionally unable to assign them to a precedently defined species of the genus. Despite the similarity of the two genera's way of life, their association proves an absence of ecologic competition between them. Eremotherium is a tropical vicariant of Megatherium, with similar dimensions and proportions. E. lundi is very abundant at Lagoa São Vitor, Garrincho and especially Barra do Antonião where it constitutes the dominant species. The local populations seems to present some peculiar anatomical characters. Eremotherium was probably a spinny bush savanna dweller, feeding mainly on twigs. It is frequently found in the Intertropical Brazil's Upper Pleistocene sites (Bahia, Pernambuco, Ceará, Paraíba, Minas Gérais). Cf. Xenocnus cearensis is a very rare form ; the genus is monospecific and exclusively known in the Upper Pleistocene of the Brazilian North East. Four isolated teeth from Barra do Antonião and probably a calcaneum from Lagoa São Vitor demonstrate its presence in the São Raimundo Nonato Archaeological Area. The four ground sloths species excavated in the São Raimundo Nonato Archaeological Area, whose three are amongst the dominant forms of the region's megafauna, are all intertropical forms very distinct from their homologous of Southern Brazil, Argentina and Andean regions. They tell in the favour of not less than three different regions in the Neotropical biogeographical Empire during the Pleistocene Era., L'endémisme de la mégafaune intertropicale d'Amérique du Sud au Pléistocène : les Paresseux terrestres géants de l'aire archéologique de São Raimundo Nonato (Piaui, Brésil). Parmi les nombreux sites archéologiques reconnus depuis quelques années dans le Sud-Est du Piaui, certains, découverts récemment, sont de type karstique ou palustre et sont fossilifères. Ils ont livré de nombreux restes de vertébrés et d'invertébrés associés à des industries du Paléolithique supérieur. Quatre espèces de paresseux terrestres géants sont représentées : les Mylodontidés Scelidotheriinés Catonyx cuvieri (Lund) et Scelidodon sp., le Megatheridé Megatheriiné Eremotherium lundi (Paula Couto) et le Megalonychidé Xenocniné cf. Xenocnus cearensis Paula Couto. Catonyx cuvieri, distinct des genres Scelidotherium et Scelidodon, est abondant à la Toca de Cima dos Pilão et à la Toca da Barra do Antonião. Il est présent au Sumidouro, à Garrincho, et probablement aussi à São Vitor. L'espèce, définie par Lund dans les grottes de Lagoa Santa (Minas Gerais), est très hypsodonte et consommait des herbes et des rameaux ; elle n'est connue qu'au Pléistocène supérieur. Elle est abondante dans le Nord-Est brésilien mais semble absente au Sud du Minas Gerais. Scelidodon sp., découvert à Garrincho associé au précédent, ne peut actuellement être attribué à une espèce déjà connue. Le mode de vie devait être semblable à celui de Catonyx sans pourtant qu'il y ait concurrence entre les deux. Eremotherium lundi appartient à un genre vicariant de Megatherium, dont il atteint les proportions. Il est abondant au Lagoa São Vitor, à Garrincho et surtout à la Barra do Antonião où il constitue l'espèce dominante, il représente près du tiers du matériel recueilli. La population de la région semble présenter quelques caractères particuliers. Eremotherium habitait la savane à buissons épineux, et consommait surtout des rameaux. Il est fréquemment signalé dans le Pléistocène supérieur du Brésil intertropical (Bahia, Pernambuco, Ceará, Paraíba et Minas Gerais). Cf. Xenocnus cearensis n'est représenté que par quatre dents isolées de la Barra do Antonião et sans doute un calcanéum de São Vitor. Le genre, monospécifique, n'est connu que dans le Nord-Est brésilien. Les quatre espèces de paresseux terrestres géants recueillis dans la région de São Raimundo Nonato, dont les deux premières comptent parmi les formes dominantes du Pléistocène supérieur de la région, sont donc toutes des formes intertropicales bien distinctes de leurs homologues du Sud du Brésil, de l'Argentine et du domaine andin. Elles confirment l'existence d'au moins trois régions distinctes dans l'empire néotropical au Pléistocène., Endemismo de la megafauna intertropical de América del Sur en el Pleistoceno : perezosos terrestres gigantes del area arqueologica de São Raimundo Nonato (Piaui, Brasil). Entre los numerosos parajes arqueológicos reconocidos hace algunos años en el Sudeste de Piaui, algunos descubiertos recientemente, son de tipo kárstico o palustre, siendo fosilíferos. Estos parajes han proporcionado numerosos restos de vertebrados e invertebrados asociados a industrias paleolíticas. Cuatro especies de perezosos terrestres gigantes se encuentran representados : los Mylodontidae Scelidotheriinae Catonyx cuvieri (Lund) y Scelidodon sp., el Megatheriidae Megatheriinae Eremotherium lundi (Paula Couto), y el Megalonychidae Xenocninae cf. Xenocnus cearensis Paula Couto. Catonyx cuvieri, distinto de los géneros Scelidotherium y Scelidodon, es abundante en la Toca de Cima dos Pilão, y en la Janela da Barra do Antonião). Se encuentra en Sumidouro, en Garrincho, y probablemente también en São Vitor. La especie, definida por Lund en las grutas de Lagoa Santa (Minas Gérais), es muy hypsodonte y consumia hierbas y ramas ; esta especie es conocida sólo en el Pleistoceno superior. Es abundante en el Nordeste brasilero, pero parece ausente al Sur de Minas Gerais. Scelidodon sp. esta encuentrado en 1992 en Garrincho asociado con Catonyx cuvieri. Eremotherium lundi pertenece a un género supletorio de Megatherium, del cual alcanza las proporciones. Es abundante en Lagoa São Vitor, en Garrincho, y sobre todo en la Barra do Antonião donde constituye la especie dominante. La población de la región parece presentar algunos caracteres particulares. Eremotherium vivía en una sabana de arbustos espinosos, y consumía sobre todo ramas. Se encuentra muy frequentemente señalado en el Pleistoceno superior del Brasil intertropical (Bahia, Pernambuco, Ceará, Paraíba y Minas Gerais). Cf. Xenocnus cearensis está únicamente representado por cuatro dientes aislados de la Barra do Antonião, y probablemente un calcaneo de São Vitor. El género, monospecífico, es conocido solo en el Nordeste del Brasil. De las cuatro especies de perezosos terrestres gigantes colectados en la región de São Raimundo Nonato, la dos primeras se cuentan entre las formas dominantes del Pleistoceno superior de la región, siendo todas formas intertropicales bien distintas de sus homólogas del Sur del Brasil y de la Argentina. Confirman la existencia de al menos tres regiones distintas en el imperio neotropical del Pleistoceno., Curvello Maria-Amelia, Guérin Claude. L'endémisme de la mégafaune intertropicale d'Amérique du Sud au Pléistocène : les paresseux terrestres géants de l'aire archéologique de São Raimundo Nonato (Piaui, Brésil). In: Documents des Laboratoires de Géologie, Lyon, n°125, 1993. Paléontologie et stratigraphie d’Amérique latine. Table ronde européenne. Lyon, 7-8-9 juillet 1992. pp. 109-117.

The study was undertaken in 10 formol-imbibed kidneys of great anteater (Myrmecophaga tridactyla). After the dissection the following characteristics were showed: kidney blood vessels are distributed in 2 different sites, namely hilar and extrahilar, amounting 3 to 6 in the right side 3 to 7 in the left side. Arterial branches in extrahilar region range from 1 to 2 in both sides and in hilar region they present from 1 to 4 in the right and 1 to 2 in the left. Venous roots occur in 1 to 2 vessels in the right and 1 to 3 vessels in the left, occupying only the hilar region, except one case where it was present in the right side.

A two-toed sloth (Choloepus didactylus) from French Guiana showed an erythrocytic parasite morphologically related to the Babesiidae family, and described as Babesia choloepi. It is the first Babesia species described in the Edentata order.

Four bacterial strains isolated from two livers of armadillos experimentally infected with Mycobacterium leprae were studied. Lipids obtained after saponification and methylation and complex lipids obtained by solvent extraction were examined. The presence of mycolates showed that the four strains belonged to the genus Mycobacterium, but the mycolate patterns, identical for the four strains, were different from those of all strains studied so far. Three of these strains contained phthioceranic acids, which were not found in the fourth one. Only the last strain contained mycosides of the C type, while the three others contained a new type of glycolipid. Their content in mycolates and in glycolipids demonstrated a clear-cut difference between these strains, on the one hand, and M. leprae on the other.