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Deep mtDNA divergences indicate cryptic species in a fig-pollinating wasp
Eleanor R Haine, Joanne Martin, James M Cook
BMC Evolutionary Biology , 2006, DOI: 10.1186/1471-2148-6-83
Abstract: We studied variation in 71 fig-pollinating wasps from across the large geographic range of Ficus rubiginosa in Australia. All wasps sampled belong to one morphological species (Pleistodontes imperialis), but we found four deep mtDNA clades that differed from each other by 9–17% nucleotides. As these genetic distances exceed those normally found within species and overlap those (10–26%) found between morphologically distinct Pleistodontes species, they strongly suggest cryptic fig wasp species. mtDNA clade diversity declines from all four present in Northern Queensland to just one in Sydney, near the southern range limit. However, at most sites multiple clades coexist and can be found in the same tree or even the same fig fruit and there is no evidence for parallel sub-division of the host fig species. Both mtDNA data and sequences from two nuclear genes support the monophyly of the "P. imperialis complex" relative to other Pleistodontes species, suggesting that fig wasp divergence has occurred without any host plant shift. Wasps in clade 3 were infected by a single strain (W1) of Wolbachia bacteria, while those in other clades carried a double infection (W2+W3) of two other strains.Our study indicates that cryptic fig-pollinating wasp species have developed on a single host plant species, without the involvement of host plant shifts, or parallel host plant divergence. Despite extensive evidence for coevolution between figs and fig wasps, wasp speciation may not always be linked strongly with fig speciation.Hosts and their symbionts often have major effects on each other's evolution. Indeed, many symbioses show coevolution of key traits, such as parasite virulence and host resistance and, in some cases, may also manifest cospeciation. A classic example of a coevolved mutualism is provided by the obligate relationship between fig trees (Ficus species) and fig-pollinating wasps (Hymenoptera:Agaonidae). Female wasps enter receptive fig syconia (inflorescences) via a nar
Comparisons of host mitochondrial, nuclear and endosymbiont bacterial genes reveal cryptic fig wasp species and the effects of Wolbachia on host mtDNA evolution and diversity
Xiao-Jing Sun, Jin-Hua Xiao, James M Cook, Gui Feng, Da-Wei Huang
BMC Evolutionary Biology , 2011, DOI: 10.1186/1471-2148-11-86
Abstract: We surveyed 76 pollinator wasp specimens from nine Ficus microcarpa trees each growing at a different location in Hainan and Fujian Provinces, China. We found that all wasps were morphologically identified as Eupristina verticillata, but diverged into three clades with 4.22-5.28% mtDNA divergence and 2.29-20.72% nuclear gene divergence. We also found very strong concordance between E. verticillata clades and Wolbachia infection status, and the predicted effects of Wolbachia on both mtDNA diversity and evolution by decreasing mitochondrial haplotypes.Our study reveals that the pollinating wasp E. verticillata on F. microcarpa has diverged into three cryptic species, and Wolbachia may have a role in this divergence. The results also indicate that Wolbachia strains infecting E. verticillata have likely resulted in selective sweeps on host mitochondrial DNA.The system of figs and fig wasps is considered to be a classic example of coevolved mutualism. It is well known that in general each fig species has a unique pollinator, which is called the "one-to-one" rule. However, more and more examples of co-pollinators (two or more pollinating wasp species on a fig) have broken the "one-to-one" rule [1-10]. However, we do not yet know how they evolve. They might be distantly related species, suggesting host shifts, or sister species, suggesting speciation on the current host [11,12]. Host shifts might be more likely when a fig colonises a new habitat, or is near the edge of its geographic range, because the normal pollinator is rare or absent. In this scenario, the co-pollinators are usually not closely related species [2,5,8]. Alternatively, sister co-pollinators may evolve from a recent speciation event in the pollinator that is not accompanied by fig radiation [3,11,12]. However, the exact mode of speciation for co-pollinators has not been well understood yet.Wolbachia bacteria are the most common intracellular bacteria in arthropods and nematodes, and can manipulate host re
Definable tree property for successors of cardinals  [PDF]
Ali Sadegh Daghighi,Massoud Pourmahdian
Mathematics , 2015,
Abstract: It is proved that the consistency strength of having definable tree property for successors of all regular cardinals is the consistency strength of having proper class many small large cardinals which are defined very similar to indescribables but are much weaker in consistency strength. Also the consistency strength of definable tree property for successor of a singular cardinal is reduced to the existence of a supercompact cardinal and a measurable above it.
Successors of Singular Cardinals and Coloring Theorems II  [PDF]
Todd Eisworth,Saharon Shelah
Mathematics , 2008,
Abstract: We investigate negative square-brackets partition relations at successors of singular cardinals of countable cofinality. Along the way we prove some club-guessing results.
Strong Tree Properties at Successors of Singular Cardinals  [PDF]
Laura Fontanella
Mathematics , 2012,
Abstract: We prove that successors of singular limits of strongly compact cardinals have the strong tree property. We also prove that aleph_{omega+1} can consistently satisfy the strong tree property.
Successors of singular cardinals and coloring theorems. I  [PDF]
Todd Eisworth,Saharon Shelah
Mathematics , 1998,
Abstract: We investigate the existence of strong colorings on successors of singular cardinals. This work continues Section 2 of [Sh:413] (math.LO/9809199), but now our emphasis is on finding colorings of pairs of ordinals, rather than colorings of finite sets of ordinals.
A Framework for Forcing Constructions at Successors of Singular Cardinals  [PDF]
James Cummings,Mirna D?amonja,Menachem Magidor,Charles Morgan,Saharon Shelah
Mathematics , 2014,
Abstract: We describe a framework for proving consistency results about singular cardinals of arbitrary cofinality and their successors. This framework allows the construction of models in which the Singular Cardinals Hypothesis fails at a singular cardinal of uncountable cofinality, while its successor enjoys various combinatorial properties. As a sample application, we prove the consistency (relative to that of ZFC plus a supercompact cardinal) of there being a strong limit singular cardinal $\kappa$ of uncountable cofinality where SCH fails and for which there is a collection of graphs on $\kappa^+$ whose size is less than $2^\kappa$ and such that any graph on $\kappa^+$ embeds into one of the graphs in the collection.
WASP_SEDDEER: Incorporation of SEDDEER into WASP  [cached]
Yi Xiong,Vladimir J. Alarcon,James L. Martin,William H. McAnally
Energy and Environment Research , 2012, DOI: 10.5539/eer.v2n1p157
Abstract: In this study, SEDDEER (Sediment Deposition and Erosion), a stand-alone sediment and contaminant model which simulates one water box and the underlying multiple sediment bed layers, was incorporated into Water Quality Analysis Simulation Program (WASP7.4). WASP7.4 toxic module (TOXI7) was modified to include SEDDEER to develop WASP_SEDDEER model. Tests were designed to ensure that the coupling of the WASP7.4 and SEDDEER bed models is correct. The tests compared WASP_SEDDEER one-box simulations against SEDDEER results to verify fluxes across the sediment-water interface. Also, two-vertical-boxes water-column model tests were performed to compare WASP_SEDDEER output against Environmental Fluid Dynamic Code (EFDC) solutions. The comparisons revealed a good fitting between WASP_SEDDEER and EFDC results (R2 values above 0.95) verifying a successful incorporation. Exploratory applications of EFDC, WASP7.4, and WASP_SEDDEER to Mobile Bay for simulating sediment and contaminant transport showed the capabilities of WASP_SEDDEER for estimating suspended sediment and contaminant concentrations throughout the computational domain.
The WASP and WAVE family proteins
Shusaku Kurisu, Tadaomi Takenawa
Genome Biology , 2009, DOI: 10.1186/gb-2009-10-6-226
Abstract: The human Wiskott-Aldrich syndrome protein (WASP) gene was the first of the WASP and WAVE family genes to be isolated, in 1994, as a mutated gene associated with Wiskott-Aldrich syndrome (WAS), an X-linked recessive disease characterized by immunodeficiency, thrombocytopenia and eczema, clinical features caused by complex defects in lymphocyte and platelet function [1]. Another WASP family member, neural (N-) WASP, was then identified from a proteomic search for mammalian proteins that interact with the Src homology 3 (SH3) domain of growth factor receptor binding protein 2 (Grb2, also known as Ash) [2]. Although expressed ubiquitously, N-WASP is most abundant in the brain - hence its name. The first WAVE protein was identified in humans by our group and another group independently as a WASP-like molecule and was named WAVE and SCAR1, respectively [3,4]. Currently, it is agreed that mammals possess five genes for the WASP and WAVE family, WASP, N-WASP, WAVE1/SCAR1, WAVE2, and WAVE3 [5-9]. Human WASP and WAVE family genes are located on different chromosomes, with each gene showing a unique expression pattern (Figure 1). The human WASP gene is carried on the X chromosome and is expressed exclusively in hematopoietic cells, which explains the inheritance pattern and the immunodeficiency and platelet deficiency characteristic of WAS. WAVE1 and WAVE3 are strongly enriched in the brain and are moderately expressed in some hematopoietic lineages, whereas WAVE2 appears to be ubiquitous.Human WASP and WAVE proteins are between 498 and 559 amino acids long and are encoded by 9 to 12 exons. The length of the genes is relatively similar, ranging from 67.1 kb for N-WASP to 131.2 kb for WAVE3, with the exception of WASP, which is a compact 7.6 kb. The restricted expression of WASP in hematopoietic cells is dependent on a 137-bp region upstream of the transcription start site [10]. It is unclear how brain-specific expression of WAVE1 and WAVE3 is regulated, but the proximal promo
FIVE UNPUBLISHED COINS OF ALEXANDER THE GREAT AND HIS SUCCESSORS IN THE RHODES UNIVERSITY COLLECTION  [cached]
J.D. Snowball,W.D. Snowball
Akroterion , 2012, DOI: 10.7445/50-0-73
Abstract: The article briefly discusses the economic and political significance of the Alexander III (“the Great”) type silver tetradrachm and publishes three of his coins currently held by the Rhodes University Classics Museum. Based on stylistic elements, they are classified as from the Amphipolis and Arados mints and were probably minted during his lifetime. Two further tetradrachms from the empires of Alexander’s successors, Ptolemy II and Seleucus IV, are also published.
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