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Dittus W.P.J.,Smithsonian Conservation Biology Institute | Dittus W.P.J.,Sri Lanka Institute of Fundamental Studies
American Journal of Physical Anthropology | Year: 2013

There is a paucity of information on body composition and fat patterning in wild nonhuman primates. Dissected adipose tissue from wild toque macaques (Macaca sinica) (WTM), feeding on a natural diet, accounted for 2.1% of body weight. This was far less than fatness reported for nonhuman primates raised in captivity or for contemporary humans. In WTM, fatness increased with age and diet richness, but did not differ by sex. In WTM (none of which were obese) intra-abdominal fat filled first, and "excess" fat was stored peripherally in a ratio of about 6:1. Intermuscular fat was minimal (0.1%). The superficial paunch held <15% of subcutaneous fat weight in contrast to its much larger proportions in obese humans and captive monkeys where most added fat accumulates subcutaneously. With increasing total adiposity, accumulating fat shifted in its distribution among eight different main internal and peripheral deposit areas - consistent with maintaining body balance and a low center of gravity. The available data suggest that, in arboreal primates, adaptations for agile locomotion and terminal branch feeding set constraints on the quantity and distribution of fat. The absence of a higher percentage of body fat in females and neonates (as are typical of humans) suggests that arboreal adaptations preclude the development of fat-dependent, large-brained infants and the adipose-rich mothers needed to sustain them. The lifestyle and body composition of wild primates represent a more appropriate model for early human foragers than well-fed captive monkeys do. Am J Phys Anthropol 152:333-344, 2013. © 2013 Wiley Periodicals, Inc. Copyright © 2013 Wiley Periodicals, Inc. Source


Benjamin S.P.,Sri Lanka Institute of Fundamental Studies | Benjamin S.P.,Smithsonian Institution
Zootaxa | Year: 2011

The higher-level phylogenetic relationships of crab spiders (Thomisidae) are studied from morphological data. 33 taxa are coded for 74 characters (53 binary and 21 multistate). Several analyses using equal, successive and implied weights were carried out. The most parsimonious tree obtained by analysis with successive and implied weights is put forward as the preferred hypothesis of thomisid relationships (length 222 steps, CI 0.74, RI 0.83). Thomisidae emerge monophyletic in all analyses, supported by four unambiguous synapomorphies. It is now apparent that thomisid taxa have been mostly defined on the basis of plesiomorphic character states. A number of taxonomic changes, including the description of new taxa are proposed and the evolution of diverse behaviors of thomisids is studied in light of the new phylogenetic result. Color change behavior evolved once within the family, but eye arrangement patterns of the median ocular quadrangle, thought to be diagnostic for many genera, evolved as much as 10 times independently. The following new species are described: Borboropactus nyerere sp. nov.,Cebrenninus srivijaya sp. nov., Geraesta lehtineni sp. nov. and Geraesta mkwawa sp. nov. The following new generic synonymies are proposed: Bucranium O. P.-Cambridge, 1881 = Aphantochilus O. P.-Cambridge, 1870; Sanmenia Song and Kim, 1992 = Pharta Thorell, 1891 and Cupa Strand, 1906 = Epidius Thorell, 1877. The following species are synonymized: Regillus divergens Hogg, 1914 and Borboropactus hainanus Song, 1993 = Borboropactus bituberculatus Simon, 1884 syn. nov., Epidius ganxiensis (Yin, Peng & Kim, 1999) = Epidius rubropictus Simon, 1909 syn. nov., Geraesta bilobata Simon, 1897 = Geraesta hirta Simon, 1889 syn. nov., Sanmenia kohi Ono, 1995 = Pharta bimaculata Thorell, 1891 syn. nov. and Sanmenia zhengi (Ono & Song, 1986) = Pharta brevipalpus (Simon, 1903) syn. nov. The following new combinations are proposed: Aphantochilus taurifrons (O. P.-Cambridge, 1881) comb. nov., Epidius typicus (Bösenberg & Strand, 1906) comb. nov., Pharta brevipalpus (Simon, 1903) comb. nov., Pharta gongshan (Yang, Zhu and Song, 2006) comb. nov., Pharta nigra (Tang, Griswold & Peng, 2009) comb. nov. and Pharta tengchong (Tang, Griswold & Yin, 2009) comb. nov. © 2011 Magnolia Press. Source


Seneviratne G.,Sri Lanka Institute of Fundamental Studies
Agriculture, Ecosystems and Environment | Year: 2015

Sustainability of natural and agro ecosystems is governed mainly by soil processes. In these, contributions of the biotic or living constituents are much important. The biotic part is represented by soil food web. Here, I argue that the sustainability of the ecosystems is an outcome of chemical signaling in the food web. Then, I show that it is the microbes living mainly endophytically and in the soil, including fauna, which contribute to ecosystem balance through signaling in complex network interactions. Sustenance of edaphic or soil ecosystems collapses when the signaling is retarded due to human impact and global change. This issue can only be addressed by manipulating soil microbes. I introduce a new term edaphic ecosystem signal transduction (EST), which can summarize the concept explained in this article. © 2015 Elsevier B.V. Source


Jaiswal R.,Jacobs University Bremen | Jayasinghe L.,Sri Lanka Institute of Fundamental Studies | Kuhnert N.,Jacobs University Bremen
Journal of Mass Spectrometry | Year: 2012

The proanthocyanidins of the leaves of 16 taxa of the Rhododendron genus (Ericaceae) [Rhododendron 'Catawbiense Grandiflorum', Rhododendron 'Cunningham's White', Rhododendron smirnowii Trautv., Rhododendron calophytum Franch., Rhododendron dichroanthum ssp. scyphocalyx (Balf. f. & Forrest) Cowan, Rhododendron micranthum Turcz., Rhododendron praevernum Hutch., Rhododendron ungernii Trautv., Rhododendron kaempferi Planch., Rhododendron degronianum ssp. heptamerum var. hondoense (Nakai) H. Hara, Rhododendron fortunei Lindl., Rhododendron ponticum L., Rhododendron galactinum Balf. f. ex Tagg., Rhododendron oreotrephes W. W. Sm., Rhododendron brachycarpum ssp. brachycarpum D. Don ex G. Don, and Rhododendron insigne Hemsl. & E. H. Wilson] were investigated qualitatively by liquid chromatography-mass spectrometry in series. Twenty-nine dimeric proanthocyanidins based on (epi)catechin and (epi)gallocatechin were detected and characterized on the basis of their unique fragmentation pattern in the negative ion mode tandem mass spectrometry spectra. All of them were extracted for the first time from these sources, and ten of them were not reported previously in nature. The position of the galloyl residue was assigned on the basis of the retro-Diels-Alder fragmentation and the dehydrated retro-Diels-Alder fragmentation; it resulted from the loss of gallic acid as a neutral loss in the negative ion mode. Furthermore, four caffeoylquinic acids, six p-coumaroylquinic acids, epigallocatechin, gallocatechin, catechin, epicatechin, epigallocatechin gallate, catechin gallate, epicatechin gallate, gallocatechin gallate, two quercetin-O-hexosides, quercetin-O-galloyl-hexoside, quercetin-O-pentoside, quercetin-O-rhamnoside, quercetin-O-pentoside-O-hexoside, quercetin-O-rhamnoside-O-hexoside, quercetin-O-feruloyl-hexoside, quercetin-O-(p-hydroxy)benzoyl-hexoside, taxifolin-O-pentoside, myricetin-O-rhamnoside, two myricetin-O-pentosides, three myricetin-O-hexosides, and two myricetin-O-galloyl-hexosides were detected and shown to possess characteristic tandem mass spectrometry spectra and were tentatively assigned on the basis of their retention time. Copyright © 2012 John Wiley & Sons, Ltd. Source


Nanayakkara A.,Sri Lanka Institute of Fundamental Studies
Journal of Physics A: Mathematical and Theoretical | Year: 2012

Dynamical tunneling occurs when a particle tunnels between two distinct classically trapped periodic regions of classical phase space that are not separated by a potential barrier. Although the dynamical tunneling has been observed in many multi-dimensional Hamiltonian systems, it has not been observed in 1D systems described by a single potential. In this paper, we show that classical trajectories of real potentials such as V 1(x) = x 4 exhibit dynamical tunneling-like behavior when energy or time is complex. It was found that the doubly periodic nature of the Jacobian elliptic functions is responsible for this dynamical tunneling-like behavior. The time spent in one region by the tunneling trajectory before crossing over to the other is found to be proportional to , where total energy E = E 0 + iΔE with E 0 < 0. Furthermore, we demonstrate that classical trajectories of the non-Hermitian system V 2(x) = x 4 + (1 + i)x show evidence of dynamical tunneling even for real energies. The role of complex time in dynamical tunneling is discussed. This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical devoted to Quantum physics with non-Hermitian operators. © 2012 IOP Publishing Ltd. Source

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