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The distributions of amphibians, birds and mammals have underpinned global and local conservation priorities, and have been fundamental to our understanding of the determinants of global biodiversity. In contrast, the global distributions of reptiles, representing a third of terrestrial vertebrate diversity, have been unavailable. This prevented the incorporation of reptiles into conservation planning and biased our understanding of the underlying processes governing global vertebrate biodiversity. Here, we present and analyse the global distribution of 10,064 reptile species (99% of extant terrestrial species). We show that richness patterns of the other three tetrapod classes are good spatial surrogates for species richness of all reptiles combined and of snakes, but characterize diversity patterns of lizards and turtles poorly. Hotspots of total and endemic lizard richness overlap very little with those of other taxa. Moreover, existing protected areas, sites of biodiversity significance and global conservation schemes represent birds and mammals better than reptiles. We show that additional conservation actions are needed to effectively protect reptiles, particularly lizards and turtles. Adding reptile knowledge to a global complementarity conservation priority scheme identifies many locations that consequently become important. Notably, investing resources in some of the world’s arid, grassland and savannah habitats might be necessary to represent all terrestrial vertebrates efficiently

2016-12-23T18:52:10

the heat?: a tale of ecology and evolution under two temperatures.Global Ecology and Biogeography, 22 (7). 834-845. 10.1111/geb.12053 Contact CEH NORA team at noraceh@ceh.ac.ukThe NERC and CEH trademarks and logos ('the Trademarks') are registered trademarks of NERC in the UK and other countries, and may not be used without the prior written consent of the Trademark owner. their geographic ranges to examine the relationships between these two measures. 49 Location: Worldwide 50Methods: We examined factors influencing body temperatures, and tested for the influence of both 51 body and mean annual temperatures on ecological and life history traits, while accounting for the 52 influence of shared ancestry. 53Results: Body temperatures and mean annual temperatures are uncorrelated. However, accounting 54 for activity time (nocturnal species have low body temperatures), use of space (fossorial and semi-55 aquatic species were "colder"), insularity (mainland species are "hotter") and phylogeny, the two 56 temperatures are positively correlated. High body temperatures are only associated with larger 57 hatchlings (contra the temperature size rule) and with increased rates of biomass production. Annual 58 temperatures are positively correlated with clutch frequency and annual longevity, and negatively 59 correlated with clutch size, age at first reproduction and longevity . High annual temperatures are 60 positively correlated with productivity and brood frequency, but negatively correlated with clutch 61 size, age at first reproduction, and longevity. 62

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Longevity is an important life-history trait, directly linked to the core attributes of fitness (reproduction and survival), yet large-scale comparative studies quantifying its implications for the ecology and life history of ectotherms are scarce. We tested the allometry of longevity in squamates and the tuatara, and determined how longevity is related to key environmental characteristics and life-history traits. Predictions based on life-history theory are expected to hold true for ectotherms, similarly to mammals and birds. Location: World-wide. Methods: We assembled from the literature a dataset of the maximum longevities of more than a thousand squamate species, representing c. 10 of their known species diversity, their phylogenetic relationships and multiple life-history and ecological variables. Correcting for phylogeny, we modelled the link between squamate longevity and both key life-history traits, such as body mass and age at first reproduction, and important environmental factors, such as latitude and primary productivity within species distributional ranges. Results: Large-bodied species live for longer than small ones, but body size explains far less of the variance in longevity than it does in mammals and birds. Accounting for body size, squamate brood frequency is negatively correlated with longevity, while age at first reproduction is positively correlated with longevity. This points to a continuum of slow-to-fast life-history strategies. Squamates in high latitudes and cold regions live for longer, probably because a shorter season of activity translates to slower development, older age at first reproduction and hence to increased longevity. Individuals live longer in captivity than in the wild. Herbivorous and omnivorous squamates live for longer than carnivorous ones. We postulate that low-quality nutrition reduces growth rates, promotes a relative decline in reproductive rates and thus prolongs life. Main conclusions: Our results support key predictions from life-history theory and suggest that reproducing more slowly and at older ages, being herbivorous and, plausibly, lowering metabolism, result in increased longevity

The amyloid hypothesis states that a variety of neurotoxic ␤-amyloid (A␤) species contribute to the pathogenesis of Alzheimer's disease. Accordingly, a key determinant of disease onset and progression is the appropriate balance between A␤ production and clearance. Enzymes responsible for the degradation of A␤ are not well understood, and, thus far, it has not been possible to enhance A␤ catabolism by pharmacological manipulation. We provide evidence that A␤ catabolism is increased after inhibition of plasminogen activator inhibitor-1 (PAI-1) and may constitute a viable therapeutic approach for lowering brain A␤ levels. PAI-1 inhibits the activity of tissue plasminogen activator (tPA), an enzyme that cleaves plasminogen to generate plasmin, a protease that degrades A␤ oligomers and monomers. Because tPA, plasminogen and PAI-1 are expressed in the brain, we tested the hypothesis that inhibitors of PAI-1 will enhance the proteolytic clearance of brain A␤. Our data demonstrate that PAI-1 inhibitors augment the activity of tPA and plasmin in hippocampus, significantly lower plasma and brain A␤ levels, restore long-term potentiation deficits in hippocampal slices from transgenic A␤-producing mice, and reverse cognitive deficits in these mice.Alzheimer ͉ plasminogen activator inhibitor ͉ tissue plasminogen activator A lzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by the presence of intracellular neuronal tangles and extracellular parenchymal and vascular amyloid deposits containing ␤-amyloid peptide (A␤). A␤ is a 39-to 42-aa peptide derived from the proteolytic processing of the amyloid precursor protein (APP) (1). The ''amyloid hypothesis'' of AD postulates a central causal role for A␤ in AD pathogenesis and is supported by genetic and physiological evidence. All known early onset familial AD mutations result in enhanced levels of cytotoxic A␤ species, amyloid plaque deposition, and dementia. Furthermore, A␤ peptide is reported to be neurotoxic and synaptotoxic in vitro and in vivo, inhibiting long-term potentiation (LTP), a physiological correlate of memory (2). Based on these observations, a number of strategies to reduce brain A␤ levels are being pursued as therapeutic approaches to treat AD (3, 4).If the amyloid hypothesis of AD is correct and A␤ levels are pivotal to disease etiology, then the balance between A␤ production and catabolism is likely to be a key determinant of disease progression. It has been suggested that insufficient clearance of A␤ may account for elevated A␤ levels in the brain and the accumulation of pathogenic amyloid deposits in sporadic AD (5). A number of proteases have been implicated in the proteolytic clearance of A␤ from the CNS, including neprilysin, insulin-degrading enzyme, endothelin converting enzyme, and plasmin (3, 6-8). The relative contribution of these enzymes to A␤ catabolism remains unclear, but each protease may play a significant role in the degradation and clearance of A␤, resulting in a slowing of A␤ accumulation and aggregation and u...

Aim: Clutch size is a key life-history trait. In lizards, it ranges over two orders of magnitude. The global drivers of spatial and phylogenetic variation in clutch have been extensively studied in birds, but such tests in other organisms are lacking. To test the generality of latitudinal gradients in clutch size, and their putative drivers, we present the first global-scale analysis of clutch sizes across lizard taxa. Location: Global. Time period: Recent. Major taxa studied: Lizards (Reptilia, Squamata, Sauria). Methods: We analysed clutch-size data for over 3,900 lizard species, using phylogenetic generalized least-square regression to study the relationships between clutch sizes and environmental (temperature, precipitation, seasonality, primary productivity, insularity) and ecological factors (body mass, insularity, activity times, and microhabitat use). Results: Larger clutches are laid at higher latitudes and in more productive and seasonal environments. Insular taxa lay smaller clutches on average. Temperature B I OS K E TCH Shai Meiri is interested in the evolution of traits, and its relationship with geography.