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Laurance W.F.,James Cook University | Laurance W.F.,Smithsonian Tropical Research Institute | Carolina Useche D.,Smithsonian Tropical Research Institute | Shoo L.P.,James Cook University | And 51 more authors.
Biological Conservation

Tropical species with narrow elevational ranges may be thermally specialized and vulnerable to global warming. Local studies of distributions along elevational gradients reveal small-scale patterns but do not allow generalizations among geographic regions or taxa. We critically assessed data from 249 studies of species elevational distributions in the American, African, and Asia-Pacific tropics. Of these, 150 had sufficient data quality, sampling intensity, elevational range, and freedom from serious habitat disturbance to permit robust across-study comparisons. We found four main patterns: (1) species classified as elevational specialists (upper- or lower-zone specialists) are relatively more frequent in the American than Asia-Pacific tropics, with African tropics being intermediate; (2) elevational specialists are rare on islands, especially oceanic and smaller continental islands, largely due to a paucity of upper-zone specialists; (3) a relatively high proportion of plants and ectothermic vertebrates (amphibians and reptiles) are upper-zone specialists; and (4) relatively few endothermic vertebrates (birds and mammals) are upper-zone specialists. Understanding these broad-scale trends will help identify taxa and geographic regions vulnerable to global warming and highlight future research priorities. © 2010 Elsevier Ltd. Source

Misof B.,Zoologisches Forschungsmuseum Alexander Koenig ZFMK | Liu S.,China National Genebank | Meusemann K.,Zoologisches Forschungsmuseum Alexander Koenig ZFMK | Meusemann K.,CSIRO | And 106 more authors.

Insects are the most speciose group of animals, but the phylogenetic relationships of many major lineages remain unresolved. We inferred the phylogeny of insects from 1478 protein-coding genes. Phylogenomic analyses of nucleotide and amino acid sequences, with site-specific nucleotide or domain-specific amino acid substitution models, produced statistically robust and congruent results resolving previously controversial phylogenetic relationships. We dated the origin of insects to the Early Ordovician [∼479 million years ago (Ma)], of insect flight to the Early Devonian (∼406 Ma), of major extant lineages to the Mississippian (∼345 Ma), and the major diversification of holometabolous insects to the Early Cretaceous. Our phylogenomic study provides a comprehensive reliable scaffold for future comparative analyses of evolutionary innovations among insects. © 2014, American Association for the Advancement of Science. All rights reserved. Source

Osswald J.,Institute For Spezielle Zoologie | Pohl H.,Institute For Spezielle Zoologie | Beutel R.G.,Institute For Spezielle Zoologie
Arthropod Structure and Development

Thoracic structures of the extremely small first instar larva of the strepsipteran species Mengenilla chobauti (ca. 200 μm) were examined, described and reconstructed 3-dimensionally. The focus is on the skeletomuscular system. The characters were compared to conditions found in other insect larvae of very small (Ptiliidae) or large (Dytiscus) size (both Coleoptera) and features of "triungulin" larvae, first instar larvae of Rhipiphoridae, Meloidae (both Coleoptera), and Mantispidae (Neuroptera). The specific lifestyle and the extreme degree of miniaturisation result in numerous thoracic modifications. Many sclerites of the exo- and endoskeleton are reduced. Cervical sclerites, pleural ridges, furcae and spinae are absent. Most of the longitudinal muscles are connected within the thorax, and a pair of ventral longitudinal muscles is present in the pleural region of the meso- and metathorax. This results in a high intersegmental flexibility. Due to the size reduction and the correlated shift of the brain to the thorax, with 94 identified muscles the thoracic musculature appears highly compact. Compared to larger larvae the number of both the individual muscles and the muscle bundles are distinctly reduced. The thorax of the first instar larvae displays many additional strepsipteran autapomorphies. At least partly due to the highly specialised condition, potential synapomorphies with other groups were not found. © 2009 Elsevier Ltd. All rights reserved. Source

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