Origins and colonization history of pandemic Vibrio parahaemolyticus in South America

The dynamics of dissemination of the environmental human pathogen Vibrio parahaemolyticus are uncertain. The O3:K6 clone was restricted to Asia until its detection along the Peruvian coasts and in northern Chile in 1997 in phase with the arrival of El Niño waters. A subsequent emergence of O3:K6 strains was detected in austral Chile in 2004. The origin of these 1997 and 2004 population radiations has not yet been conclusively determined. Multiple loci VNTR analysis using seven polymorphic loci was carried out with a number of representative strains from Asia, Peru and Chile to determine their genetic characteristics and population structure. Asian and Chilean subpopulations were the most genetically distant groups with an intermediate subpopulation in Peru. Population structure inferred from a minimum‐spanning tree and Bayesian analysis divided the populations into two genetically distinct groups, consistent with the epidemic dynamics of the O3:K6 clone in South America. One group comprised strains from the original Asiatic population and strains arriving in Peru and Chile in 1997. The second group included the remaining Peruvian Strains and Chilean strains obtained from Puerto Montt in 2004. The analysis of the arrival of the O3:K6 clone at the Pacific coasts of South America has provided novel insights linking the origin of the invasion in 1997 to Asian populations and describing the successful establishment of the O3:K6 populations, first in Peru and subsequently in the South of Chile owing to a possible radiation of Peruvian populations.     

Climate change cannot be entirely responsible for soil carbon loss observed in England and Wales, 1978–2003

We present results from modelling studies, which suggest that, at most, only about 10–20% of recently observed soil carbon losses in England and Wales could possibly be attributable to climate warming. Further, we present reasons why the actual losses of SOC from organic soils in England and Wales might be lower than those reported.     

When the pond turtle followed the reindeer: effect of the last extreme global warming event on the timing of faunal change in Northern Europe

Faunal communities have been shaped in different ways by past climatic change. The impact of the termination of the last Glacial and the onset of the present (Holocene) Interglacial on large‐scale faunal shifts, extinction dynamics and gene pools of species are of special interest in natural sciences. A general pattern of climate‐triggered range expansion and local extinction of vertebrate species is known for Europe, and shows that in the modern temperate zone the main faunal change took place mainly during the Late Glacial (14 700–11 700 years ago) and Early Holocene (11 700–9 100 years ago). Based on large datasets of new radiocarbon data, we present precise temporal dynamics of climate‐driven disappearance and appearance of reindeer and pond turtle in southern Sweden. These two species are significant climate indicators in Late Quaternary biostratigraphy. Our data reveal that the reindeer disappeared from southern Sweden ca. 10 300 years ago, whereas the pond turtle colonized the area ca. 9 860 years ago, with a 450‐year gap between each species. This provides evidence for a sudden environmental turnover, causing the replacement of an arctic faunal element by a thermophilic species. The postglacial range dynamics of pond turtle and reindeer are a unique model case, allowing insights into the faunal turnover of other vertebrates during the last dramatic natural global warming event at the Pleistocene–Holocene transition.     

Habitat-Suitability Bounds for Nesting Cover of Northern Bobwhites on Semiarid Rangelands

ABSTRACT Northern bobwhite (Colinus virginianus) is a species for which extensive knowledge exists regarding its ecology, life history, and habitat. Although the qualitative aspects of bobwhite habitat have been described and known for many decades, researchers have neglected to characterize bobwhite habitat quantitatively (i.e., habitat selection). Thus, biologists have been capable of identifying components that compose bobwhite habitat but have only been able to speculate on how much of each component was necessary. We documented selection-avoidance behavior of nesting bobwhites in Brooks County, Texas, USA, during May-August, 2004–2005. We measured 5 vegetation features (i.e., nesting-substrate ht and width, suitable nest clump density, herbaceous canopy coverage, and radius of complete visual obstruction) at nest sites (n = 105) and at random points (n = 204). We used continuous selection functions to assess habitat use and identify bounds of suitability. Selection domains for nesting-substrate height and radius of complete visual obstruction were 16.9–31.2 cm and 1.05-4.35 m, respectively. Across all measurements, bobwhites selected for nest sites with a nesting-substrate width ≥22.4 cm, suitable nest-clump density ≥730 nest clumps/ha, and herbaceous canopy coverage ≥36.7%. This knowledge will provide an important foundation for managers to evaluate current nesting conditions on semiarid rangelands and provide a basis for habitat management aimed at creating suitable nesting habitat for bobwhites.