Lineage separation and divergence form a temporally extended process whereby populations may diverge genetically, morphologically, or ecologically, and these contingent properties of species provide the operational criteria necessary for species delimitation. We inferred the historical process of lineage formation in the coast horned lizard (Phrynosoma coronatum) species complex by evaluating a diversity of operational species criteria, including divergence in mtDNA (98 specimens; 2,781 bp) and nuclear loci (RAG؊1, 1,054 bp; BDNF 529 bp), ecological niches (11 bioclimatic variables; 285 unique localities), and cranial horn shapes (493 specimens; 16 landmarks). A phylogenetic analysis of mtDNA recovers 5 phylogeographic groups arranged latitudinally along the Baja California Peninsula and in California. The 2 southern phylogeographic groups exhibit concordance between genetic, morphological, and ecological divergence; however, differentiation is weak or absent at more recent levels defined by phylogeographic breaks in California. Interpreting these operational species criteria together suggests that there are 3 ecologically divergent and morphologically diagnosable species within the P. coronatum complex. Our 3-species taxonomic hypothesis invokes a deep coalescence event when fitting the mtDNA genealogy into the species tree, which is not unexpected for populations that have diverged recently. Although the hypothesis that the 3 phylogeographic groups distributed across California each represent distinctive species is not supported by all of the operational species criteria evaluated in this study, the conservation status of the imperiled populations represented by these genealogical units remains critical.evolution ͉ geometric morphometrics ͉ niche modeling ͉ phylogeography ͉ speciation

Background and Purpose-We wished to examine the effectiveness of an early hospital discharge and home-based rehabilitation scheme for patients with acute stroke. Methods-This was a randomized, controlled trial comparing early hospital discharge and home-based rehabilitation with usual inpatient rehabilitation and follow-up care. The trial was carried out in 2 affiliated teaching hospitals in Adelaide, South Australia. Participants were 86 patients with acute stroke (mean age, 75 years) who were admitted to hospital and required rehabilitation. Forty-two patients received early hospital discharge and home-based rehabilitation (median duration, 5 weeks), and 44 patients continued with conventional rehabilitation care after randomization. The primary end point was self-reported general health status (SF-36) at 6 months after randomization. A variety of secondary outcome measures were also assessed. Results-Overall, clinical outcomes for patients did not differ significantly between the groups at 6 months after randomization, but the total duration of hospital stay in the experimental group was significantly reduced (15 versus 30 days; PϽ0.001). Caregivers among the home-based rehabilitation group had significantly lower mental health SF-36 scores (mean difference, 7 points). Conclusions-A policy of early hospital discharge and home-based rehabilitation for patients with stroke can reduce the use of hospital rehabilitation beds without compromising clinical patient outcomes. However, there is a potential risk of poorer mental health on the part of caregivers. The choice of this management strategy may therefore depend on convenience and costs but also on further evaluations of the impact of stroke on caregivers.

No abstract

Responding to the urgent need to make biodiversity records broadly accessible, the natural history community turned to “the cloud.”

Background and Purpose-The goal of the present study was to examine the resource and economic implications of an early hospital discharge and home-based rehabilitation scheme for patients with acute stroke. Methods-A cost minimization analysis in conjunction with a randomized controlled trial was carried out at 2 affiliated teaching hospitals in the southern metropolitan region of Adelaide, South Australia, between 1997 and 1998. Eighty-six hospitalized patients with acute stroke who required rehabilitation were randomized to receive both early hospital discharge and home-based rehabilitation, or conventional in-hospital rehabilitation and community care. Direct and indirect costs related to stroke rehabilitation were calculated, including hospital bed days, home-based intervention program, community services, and personal expenses during the 6 months after randomization. Results-The mean cost per patient was lower for patients randomized to the early hospital discharge and home-based rehabilitation ($8040) compared with those who received conventional care ($10 054). This cost saving was not statistically significant (Pϭ0.14). However, sensitivity analyses indicated that the cost of home-based rehabilitation was consistently lower than that of conventional care except when hospital costs were assumed to be 50% less than those used in the main analysis. Multiple regression analysis demonstrated that the cost of the home-based program was significantly related to a patient's level of disability after adjustment for age, comorbidity, and the presence or absence of a caregiver. Conclusions-The early hospital discharge and home-based rehabilitation scheme was less costly than conventional hospital care for patients with stroke. Limitation of the provision of such services to patients with mild disability is likely to be most cost effective.

No abstract

No abstract

Snake venoms represent an enriched system for investigating the evolutionary processes that lead to complex and dynamic trophic adaptations. It has long been hypothesized that natural selection may drive geographic variation in venom composition, yet previous studies have lacked the population genetic context to examine these patterns. We leverage range-wide sampling of Mojave Rattlesnakes (Crotalus scutulatus) and use a combination of venom, morphological, phylogenetic, population genetic, and environmental data to characterize the striking dichotomy of neurotoxic (Type A) and hemorrhagic (Type B) venoms throughout the range of this species. We find that three of the four previously identified major lineages within C. scutulatus possess a combination of Type A, Type B, and a ‘mixed’ Type A + B venom phenotypes, and that fixation of the two main venom phenotypes occurs on a more fine geographic scale than previously appreciated. We also find that Type A + B individuals occur in regions of inferred introgression, and that this mixed phenotype is comparatively rare. Our results support strong directional local selection leading to fixation of alternative venom phenotypes on a fine geographic scale, and are inconsistent with balancing selection to maintain both phenotypes within a single population. Our comparisons to biotic and abiotic factors further indicate that venom phenotype correlates with fang morphology and climatic variables. We hypothesize that links to fang morphology may be indicative of co-evolution of venom and other trophic adaptations, and that climatic variables may be linked to prey distributions and/or physiology, which in turn impose selection pressures on snake venoms.