Human-Mediated Emergence as a Weed and Invasive Radiation in the Wild of the CD Genome Allotetraploid Rice Species (Oryza, Poaceae) in the Neotropics

BACKGROUND: The genus Oryza is being used as a model in plant genomic studies although there are several issues still to be resolved regarding the spatio-temporal evolution of this ancient genus. Particularly contentious is whether undated transoceanic natural dispersal or recent human interference has been the principal agent determining its present distribution and differentiation. In this context, we studied the origin and distribution history of the allotetraploid CD rice genome. It is endemic to the Neotropics but the genus is thought to have originated in the Paleotropics, and there is relatively little genetic divergence between some orthologous sequences of the C genome component and their Old World counterparts. METHODOLOGY/PRINCIPAL FINDINGS: Because of its allotetraploidy, there are several potential pitfalls in trying to date the formation of the CD genome using molecular data and this could lead to erroneous estimates. Therefore, we rather chose to rely on historical evidence to determine whether or not the CD genome was present in the Neotropics before the arrival of Columbus. We searched early collections of herbarium specimens and studied the reports of explorers of the tropical Americas for references to rice. In spite of numerous collectors traveling inland and collecting Oryza, plants determined as CD genome species were not observed away from cultivated rice fields until 1869. Various arguments suggest that they only consisted of weedy forms until that time. CONCLUSIONS/SIGNIFICANCE: The spatio-temporal distribution of herbarium collections fits a simple biogeographical scenario for the emergence in cultivated rice fields followed by radiation in the wild of the CD genome in the Neotropics during the last four centuries. This probably occurred from species introduced to the Americas by humans and we found no evidence that the CD genome pre-existed in the Old World. We therefore propose a new evolutionary hypothesis for such a recent origin of the CD genome. Moreover, we exemplify how an historical approach can provide potentially important information and help to disentangle the timing of evolutionary events in the history of the Oryza genomes

Pollen analysis of Holocene sediments from the Poço das Antas National Biological Reserve, Silva Jardim, Rio de Janeiro, Brazil

The Poço das Antas National Biological Reserve is located in Rio de Janeiro State, southeast Brazil. This paper presents information on past environmental characteristics of the area through pollen analysis. Two sedimentary columns were collected and five samples were selected for radiocarbon dating. The following ages of the columns from bottom to top were detected: column 1 - 1.20-1.16 m: 6080 ±40 years BP, 0.775-0.735 m: 4090 ±40 years BP, 0.385-0.345 m: 1880 ±80 years BP; column 2 - 1.22-1.18 m: 3520 ±40 years BP, 0.23-0.19 m: 1810 ±40 years BP. Three samples from column 1 and two samples from column 2 were selected for pollen analysis: 1.20 m, 0.77 m and 0.37 m of column1 and 1.22 m and 0.21 m of column 2. Chemical treatment followed standard methodology. The palynological analysis shows that around 6080 years BP the study area was dominated by a rain forest and from around 4090 years BP the vegetation changed to a fragmented forest, restricted to low hills and surrounded by an open area of grassland and pioneer plants, swamps and peat areas. The pollen assemblage of the samples 3520, 1880 and 1810 years BP suggest the permanence of this kind of vegetation between 4000 years BP and the actual.<br>A Reserva Biológica de Poço das Antas localiza-se no Estado do Rio de Janeiro, na região sudeste do Brasil. O presente estudo teve por objetivo fornecer informações a respeito de características ambientais pretéritas da área por meio de análises palinológicas. Foram coletadas duas colunas de sedimentos e cinco amostras foram selecionadas para datação pelo método de radiocarbono, revelando as seguintes idades, da base ao topo dos testemunhos: coluna 1 - 1,20-1,16 m: 6080 ± 40 anos AP, 0,775-0,735 m: 4090 ± 40 anos AP e 0,38-0,34 m: 1880 ± 80 anos AP; coluna 2 - 1,22-1,18 m: 3520 ± 40 anos AP e 0,23-0,19 m, 1810 ± 40 anos AP. Foram retiradas três amostras da coluna 1 e duas da coluna 2 para análise palinológica: 1,20 m, 0,77 e 0,37 m da coluna 1 e 1,22 m e 0,21 m da coluna 2. O tratamento químico foi baseado em metodologia padrão de preparação de amostras palinológicas. A análise palinológica indica que em torno de 6080 anos AP a área de estudo era dominada pela Floresta Ombrófila e que, por volta de 4090 anos AP, a vegetação tinha mudado para uma floresta fragmentada, restrita às baixas colinas circundadas por áreas de campo aberto, pantanosas e turfosas. A permanência desse tipo de vegetação entre 4000 anos AP e o atual é sugerida pelas amostras datadas de 3520,1880 e 1810 anos AP

The status of the name Alysium holtingii C. Agardh, a red alga described from Brazil, and a depiction of the type specimen

The type specimen of the red alga Alysium holtingii C. Agardh, described from Brazil, is located in the Lund Herbarium, and it is depicted for the first time in a publication. It is taxonomically identical to Dichotomaria obtusata (J. Ellis and Solander) Lamarck and thus can be treated as a later taxonomic synonym. Alysium is regarded as congeneric with Dichotomaria.<br>O espécime tipo da alga vermelha Alysium holtingii C. Agardh, descrito para o Brasil, está localizado no Herbário Lund, e é aqui apresentado. Ele é taxonomicamente idêntico a Dichotomaria obtusata (J. Ellis e Solander) Lamarck e portanto deve ser tratado como um sinônimo taxonômico posterior. Alysium é considerado como congenérico com Dichotomaria

Animal-based medicines: biological prospection and the sustainable use of zootherapeutic resources

Animals have been used as medicinal resources for the treatment and relieve of a myriad of illnesses and diseases in practically every human culture. Although considered by many as superstition, the pertinence of traditional medicine based on animals cannot be denied since they have been methodically tested by pharmaceutical companies as sources of drugs to the modern medical science. The phenomenon of zootherapy represents a strong evidence of the medicinal use of animal resources. Indeed, drug companies and agribusiness firms have been evaluating animals for decades without paying anything to the countries from where these genetic resources are found. The use of animals' body parts as folk medicines is relevant because it implies additional pressure over critical wild populations. It is argued that many animal species have been overexploited as sources of medicines for the traditional trade. Additionally, animal populations have become depleted or endangered as a result of their use as experimental subjects or animal models. Research on zootherapy should be compatible with the welfare of the medicinal animals, and the use of their by-products should be done in a sustainable way. It is discussed that sustainability is now required as the guiding principle for biological conservation.<br>Os animais são utilizados como recursos medicinais para o tratamento e alívio de um gama de doenças e enfermidades em praticamente toda cultura humana. A pertinência da medicina tradicional baseada em animais, embora considerada como superstição, não deve ser negada uma vez que os animais têm sido testados metodicamente pelas companhias farmacêuticas como fontes de drogas para a ciência médica moderna. O fenômeno da zooterapia representa uma forte evidência do uso medicinal de recursos animais. De fato, as indústrias farmacêuticas e de agronegócios há décadas vêm avaliando animais sem pagar tributos aos países detentores desses recursos genéticos. A utilização de partes do corpo dos animais como remédios tradicionais é relevante porque implica pressão adicional sobre populações selvagens críticas. Discute-se que muitas espécies animais estão sendo exploradas em excesso como fontes de medicamentos para o comércio tradicional. Além disso, as populações animais ficaram exauridas ou ameaçadas como resultado do uso como objetos de experimentação ou modelos animais. A pesquisa sobre zooterapia deveria ser compatível com o bem-estar dos animais, assim como o uso dos produtos medicinais deveria ser guiado de modo sustentável. Sabe-se que a sustentabilidade deve ser tida como um princípio orientador para a conservação biológica