Bayesian phylogeography of the Arawak expansion in lowland South America

Phylogenetic inference based on language is a vital tool for tracing the dynamics of human population expansions. The timescale of agriculture-based expansions around the world provides an informative amount of linguistic change ideal for reconstructing phylogeographies. Here we investigate the expansion of Arawak, one of the most widely dispersed language families in the Americas, scattered from the Antilles to Argentina. It has been suggested that Northwest Amazonia is the Arawak homeland based on the large number of diverse languages in the region. We generate language trees by coding cognates of basic vocabulary words for 60 Arawak languages and dialects to estimate the phylogenetic relationships among Arawak societies, while simultaneously implementing a relaxed random walk model to infer phylogeographic history. Estimates of the Arawak homeland exclude Northwest Amazonia and are bi-modal, with one potential homeland on the Atlantic seaboard and another more likely origin in Western Amazonia. Bayesian phylogeography better supports a Western Amazonian origin, and consequent dispersal to the Caribbean and across the lowlands. Importantly, the Arawak expansion carried with it not only language but also a number of cultural traits that contrast Arawak societies with other lowland cultures.     

Flooding and soil composition determine beta diversity of lowland forests in Northern South America

Beta diversity may be determined by dispersal limitation, environment, and phylogeographic history. Our objective was to advance the understanding of plant species turnover in rain forests in northern South America and determine which factors are affecting species beta diversity. We evaluated the relative effect of environmental variables (i.e., soil, climate, fragmentation, and flooding frequency) and dispersal limitation (i.e., geographical distance and resistance distance due mountain barriers) on tree beta diversity in 32 1‐ha lowland forest plots. We found that tree species turnover was better explained by environmental distance than by geographical distance. Although soil conditions and flooding regime were good predictors of tree species composition, almost half of the variance remained unexplained. In our study system, the eastern Andean ridge had no significant effect on plant beta diversity, probably because of its young age in relation to the phylogeny. Our results provide support for the importance of environmental factors and suggest a more restricted role of dispersal limitation. Therefore, we advise that conservation strategies of lowland trees should consider specific forest types (e.g., seasonally flooded vs. terra firme, as well as piedmont vs. central Amazonian forests).     

Village division in lowland South America: The case of the Bakairí Indians of central Brazil

A Brazilian Indian village divided into several settlements during the 1980s. In this article, the political ecology approach is used to account for the process whereby this occurred. Data on ecology, subsistence practices, demography, and regional dynamics are presented. Analysis of results explores the articulation between shifts in population levels both in the region and in the Indian reservation, on one hand, with environmental stresses on reservation resources. The effects on national economic development programs on the regional and local levels are also discussed. The relationship between these policies and programs, on one hand, and alterations in local production systems are made explicit.     

Phylogeny of the mayfly family Leptohyphidae (Insecta: Ephemeroptera) in South America

Abstract.  A cladistic analysis of the South American members of the Ephemeropteran family Leptohyphidae is presented. A matrix of 73 taxa and 124 morphological characters was analysed under two distinct weighting criteria (implied weighting, which weights characters as a whole, and self-weighted optimization, which differentially weights character state transformations). To assess the monophyly of the Leptohyphidae, representatives of Ephemerellidae, Ephemerythidae, Machadorythidae, Teloganodidae, Tricorythidae, Coryphoridae and Melanemerellidae were also included. Trees were rooted in Ephemerellidae. Conspicuous differences in consensus topology occur when transformation costs among character states are weighted (including asymmetries). The differences in the assessments of character reliability in the two weighting criteria used are discussed. In many cases, self-weighting, in allowing for asymmetries in transformation costs, considered many of the character state transformations as more reliable (= informative) than implied weights (which needlessly down-weighted the whole character). The results confirm the monophyly of Leptohyphidae and support its sister-group relationship with Coryphoridae. The shortest trees do not support the recently proposed division of Leptohyphidae into two subfamilies. Ephemerelloidea higher classification is discussed briefly.     

Cladistic analysis of the family Baetidae (Insecta: Ephemeroptera) in South America

The family Baetidae, which belongs to the order Ephemeroptera, was first described by Leach in 1815 . Since then, almost 100 genera and 900 species have been described. Although diverse, this family is relatively homogeneous. The adults are extremely similar to one another, the wings vary little and the penes are membranous, features that significantly reduce differentiation among taxa. In contrast, the larvae have more conspicuous differences. Most are collector–gatherers, but a few are carnivorous or filter feeders. In South America, although knowledge concerning the 27 genera and 132 species of Baetidae described for this region has improved in the last three decades, phylogenetic relationships remain unknown. The present study, the first cladistic analysis of Baetidae in South America, included 70 species (55 are Neotropical) and 126 morphological characters. The matrix was analysed using tnt , under implied weights. Although the monophyly of the family Baetidae was obtained with good support, the subfamilies proposed originally (Baetinae, Cloeoninae and Callibaetinae) were recovered as paraphyletic. The Baetodes complex, as well as the relationships between genera, is discussed. The validity of some structures or characters as support of different groupings is also discussed.     

Body counts in lowland South American violence

Violence was likely often a strong selective pressure in many traditional lowland South American societies. A compilation of 11 anthropological studies reporting cause of death shows that violence led to about 30% of adult deaths, of which about 70% were males. Here violent deaths are further itemized at the level of ethnographically-reported death events (particular duels, homicides, and raids) to provide more detailed insight into the causes and consequences of within- and between-group violence. Data for 238 death events (totaling 1145 deaths) from 44 lowland South American societies show that attacks are more deadly when treachery is used, when avenging a previous killing, and on external warfare raids between ethnolinguistic groups. That revenge raids kill more people on average than the original grievance, at least when conflicts are between ethnolinguistic groups, indicates a tendency towards increasingly vicious cycles of revenge killings. Motives of killings as noted in ethnographic sources, in order of importance, reportedly include revenge for previous killings and other wrong-doings like sorcery, jealousy over women, gain of captive women and children, fear or deterrence of impending attack, and occasionally the theft of material goods. Results may have implications for understanding the potential for multi-level selection by delineating the force of competition at varying scales of analysis within and between lowland South American societies.     

Cytogenetics of Batrachyla species (Anura: Neobatrachia: Ceratophryidae) of southern South America,with phylogenetics comments

Abstract

A comparative cytogenetic analysis showed that B. antartandica, B. leptopus, B. nibaldoi and B. taeniata share the same diploid number 2n = 26, but not the same fundamental number (FN), which was 52 in B. leptopus and 50 in the other three species. The karyotype of B. nibaldoi, including C‐band patterns and locations of the NORs, are described for the first time. The C‐band patterns were species‐specific and were helpful in distinguishing taxa. Batrachyla leptopus can be distinguished from its congeners by the absence of telocentric chromosomes and by secondary constrictions in the long arms of pair 6 and short arms of pairs 7 and 11. The chromosomal data suggest that Batrachyla might be a paraphyletic genus.     

A new family of Gonyleptoidea from South America (Opiliones,Laniatores)

A new family of Laniatores, Gerdesiidae fam. nov., is proposed based on molecular and morphological evidence. Data also indicate that this new family is the sister family of Tricommatidae. Gerdesiidae fam. nov. has a disjunct distribution, occurring in northern South America (Peru, Brazilian Amazon) and at a spot in south‐eastern Brazil (Minas Gerais State). The new family is composed of two genera: Gerdesius Roewer, 1952 (type genus) and G onycranaus gen. nov. (type species G onycranaus androgynus sp. nov. ). We propose the synonymy of Huralvioides H. Soares, 1970 with Gerdesius Roewer, 1952 based on molecular and morphological evidence. Three new species are described: G erdesius mapinguari sp. nov. (type locality: Brazil, Amazonas, Manaus, Reserva Km 41); G onycranaus androgynus sp. nov. (type locality: Brazil, Minas Gerais, Conceição do Mato Dentro); and an obligate cave‐dwelling species, G onycranaus pluto sp. nov. (type locality: Brazil, Minas Gerais, Morro do Pilar). © 2015 The Linnean Society of London     

Patterns of endemism in the limestone flora of South African lowland fynbos

Taxonomie and biological aspects of endemism and Red Data Book status were studied amongst the limestone endemics of the lowland fynbos in the Cape Floristic Region, South Africa. Of the 110 limestone endemics, 1.8% are widely distributed in the Cape Floristic Region and 56.4% are regional endemics. Relative to flora of non-limestone lowland fynbos (n=538 species), the families which were overrepresented in terms of limestone endemics included the Ericaceae, Fabaceae, Polygalaceae, Rutaceae and Sterculiaceae. The Restionaceae was the only underrepresented family. The local limestone endemics were not significantly different from regional endemics in terms of their biological attributes. An analysis of the frequency of the biological traits associated with the limestone-endemic flora established a biological profile for a limestone endemic: a dwarf-to-low shrub with soil-stored seeds which are ant or wind dispersed. In terms of the species richness of limestone endemics, the De Hoop Nature Reserve was the hotspot within the region. Relative to the total species richness, the Hagelkraal and Stilbaai areas contained higher-than-predicted numbers of rare species. These areas require urgent attention if the unique floral diversity associated with limestone substrata within the Bredasdorp-Riversdale centre of endemism is to be conserved.     

Palm Management in South America

We reviewed information on management of useful palms in South America. We documented management for 96 species, from incidental activities intended to increase populations of wild palms to the inclusion of palms in complex agroforestry systems. Two species, Bactris gasipaes and Parajubaea cocoides, are domesticated. Managed species are remarkably fewer than species used in the region, which suggests that harvesters often disregard the fate of the species they use. The best way of managing palms is to employ harvest methods that do not decimate the populations. Although a variety of harvesting techniques have been documented, overharvest is common, and mismanagement prevails – unnecessary felling of palms in order to harvest leaves or fruits is a widespread practice. Research should focus on assessing production in response to management practices, but eradicating the habit of destructive harvest is an obvious priority. Research on palm management must be combined with actions addressed to all stakeholders of the palm/humans system.     

Ceremonial Dialogues in South America

In native South America, ceremonial dialogue is a widespread and prominent, yet simultaneously enigmatic, form of ritualized language use. This paper examines the ceremonial dialogic complex through the interpretive lens of a semiotic hypothesis, namely, that ritualized dialogic form is a sign vehicle, a "model of and for" linguistic and more generally social solidarity. A comparative correlational study confirms this semiotic interpretation, showing that the ceremonial dialogue is used in situations of potential conflict—the maximally distant social relations within a given society. This paper also raises a broader theoretical issue concerning the role of metacommunicative devices in social action, suggesting that it is the "meta-signal" itself that enables actors to formulate an image of action—thereby regulating it—simultaneously as it occurs.