The phylogenetic affinities of the extinct glyptodonts

Among the fossils of hitherto unknown mammals that Darwin collected in South America between 1832 and 1833 during the Beagle expedition [1] were examples of the large, heavily armored herbivores later known as glyptodonts. Ever since, glyptodonts have fascinated evolutionary biologists because of their remarkable skeletal adaptations and seemingly isolated phylogenetic position even within their natural group, the cingulate xenarthrans (armadillos and their allies [2]). In possessing a carapace comprised of fused osteoderms, the glyptodonts were clearly related to other cingulates, but their precise phylogenetic position as suggested by morphology remains unresolved [3,4]. To provide a molecular perspective on this issue, we designed sequence-capture baits using in silico reconstructed ancestral sequences and successfully assembled the complete mitochondrial genome of Doedicurus sp., one of the largest glyptodonts. Our phylogenetic reconstructions establish that glyptodonts are in fact deeply nested within the armadillo crown-group, representing a distinct subfamily (Glyptodontinae) within family Chlamyphoridae [5]. Molecular dating suggests that glyptodonts diverged no earlier than around 35 million years ago, in good agreement with their fossil record. Our results highlight the derived nature of the glyptodont morphotype, one aspect of which is a spectacular increase in body size until their extinction at the end of the last ice age.Facultad de Ciencias Naturales y Muse

The phylogenetic affinities of the extinct glyptodonts

Among the fossils of hitherto unknown mammals that Darwin collected in South America between 1832 and 1833 during the Beagle expedition [1] were examples of the large, heavily armored herbivores later known as glyptodonts. Ever since, glyptodonts have fascinated evolutionary biologists because of their remarkable skeletal adaptations and seemingly isolated phylogenetic position even within their natural group, the cingulate xenarthrans (armadillos and their allies [2]). In possessing a carapace comprised of fused osteoderms, the glyptodonts were clearly related to other cingulates, but their precise phylogenetic position as suggested by morphology remains unresolved [3,4]. To provide a molecular perspective on this issue, we designed sequence-capture baits using in silico reconstructed ancestral sequences and successfully assembled the complete mitochondrial genome of Doedicurus sp., one of the largest glyptodonts. Our phylogenetic reconstructions establish that glyptodonts are in fact deeply nested within the armadillo crown-group, representing a distinct subfamily (Glyptodontinae) within family Chlamyphoridae [5]. Molecular dating suggests that glyptodonts diverged no earlier than around 35 million years ago, in good agreement with their fossil record. Our results highlight the derived nature of the glyptodont morphotype, one aspect of which is a spectacular increase in body size until their extinction at the end of the last ice age.Facultad de Ciencias Naturales y Muse

Contaminação por agrotóxico em população de área urbana: Petrópolis, RJ

É bastante conhecido o risco de contaminação por agrotóxicos das populações de áreas rurais, principalmente trabalhadores agrícolas. Pouco comum, no entanto, é a constatação de população, em área urbana, sofrer esse tipo de contaminação, da mesma forma que na área rural, e não como acidente em locais de fabricação. Este trabalho procura descrever como a equipe da Secretaria Municipal de Saúde de Petrópolis tomou conhecimento de uma possível intoxicação por organofosforado em população urbana local, e as medidas de controle adotadas. Utilizou-se, no estudo, inquérito epidemiológico, com população previamente definida por amostragem, confirmando-se a hipótese através do teste do qui-quadrado (x²).<br>It's well-known enough the risk of contamination by agrotoxines of the rural area population, mainly agricultural workers. Not common, nevertheless, is the conclusion that the urban area population suffers from this kind of contamination as well as the one in the rural area, and not only in case of accidents in manufacturing places. This work aims to describe how the team of the Community Health Service of Petrópolis became aware of a possible intoxication by organophosphate insecticides in a local urban population, and the control attitude adopted. We used in this study, epidemiological inquiries, with the population previously defined by sampling, confirming the hypothesis by means of chi-square test (x²)