The systematic importance of anatomical data in Gagea (Liliaceae) from the Flora Iranica area

Anatomical features of basal leaves, pedicels and tepals of 22 species of Gagea belonging to four sections (Platyspermum, Plecostigma, Gagea and Didymobulbos) are investigated. Anatomical characters are mapped onto a molecular phylogenetic tree and their evolution is evaluated. The systematic importance of the anatomical characters is discussed. Anatomical characters are more systematically useful in the Irano‐Turanian taxa than in Euro‐Siberian taxa. The presence of collenchyma and/or sclerenchyma and the pentagonal outline of the transverse section of the basal leaf is found in Irano‐Turanian taxa of section Platyspermum and is mostly absent in Euro‐Siberian taxa. A diagnostic key based on combined anatomical characters is provided. The level of variation in anatomical characters is greater in the basal leaf than the pedicel and lowest in the tepals. Convergent evolution in anatomical characters is associated with ecological shifts between sunny, open, dry habitats and closed, humid habitats. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 164 , 155–177.     

Performance of polyvoltine silkworm Bombyx mori L. on different mulberry plant varieties

Five cultivated mulberry plant varieties, BSRM‐34, BSRM‐56, BSRM‐57, BSRM‐58 and BSRM‐59, were used to evaluate the effects of plant variety on larval and cocoon characteristics of mulberry silkworm Bombyx mori L. Silkworm larvae undergo their entire larval periods on leaves of mulberry varieties. Different larval characteristics of larval weight, larval length and larval breadth were measured in different growth stages. After rearing, the fifth instar larvae were transferred into a mountage (Chandraki) structure for cocoon rearing for spinning and cocoon production. The cocoons were then harvested and different cocoon characteristics like cocoon weight, shell weight and shell percentage; and other characters like pupal weight and effective rate of rearing were measured. The results showed statistically significant differences among different varieties on larval and cocoon characteristics. The highest performance was observed by feeding the variety BSRM‐34 in respect of the average weight of 10 mature larvae (40.5 g), single mature larval length (7.6 cm) and breadth (1.0 cm), single cocoon weight (1.4 g), shell weight (0.2 g) and pupal weight (1.2 g) while the average performance was recorded by feeding varieties BSRM‐57 and BSRM‐59. The poorest performance was showed by feeding the variety BSRM‐56 (in case of larval characters) and BSRM‐58 (in case of cocoon characteristics). These two varieties also showed the poorest performance for silk yield. Through comparing all the above parameters it was concluded that BSRM‐34 is the best mulberry variety and it is recommended that Bangladeshi farmers adopt that variety for better yield of silk.     

Projection of older Australians with a history of midlife obesity and overweight 2010–2050

Objective: This study projects midlife obesity status in future older Australians. Design and Methods: Cross‐sectional prevalence of being obese or overweight by broad age groups was interpolated to obtain single‐year‐age data. These estimates were then used to derive prevalence of normal weight and underweight. Data by birth year and year of observation of persons aged 30–70 years were used to construct prediction equations. Results: Results show that older people with a history of midlife obesity is projected to rise substantially in the future. For people aged 65 years, midlife obesity was estimated at 22% in 2010 and is projected to increase to 43% for males and 37% for females in 2050. Conclusion: While the proportion of individuals with midlife normal weight is projected to decline substantially, prevalence of midlife overweight remains almost stable. The number of persons aged 65 years and over having a history of midlife obesity is projected to increase nearly six‐fold from less than 500,000 persons in 2010 to 2.8 million in 2050. In comparison, between 2010 and 2050, Australia's older population aged 65 years and over is projected to increase by only 2.5‐fold. Growing obesity prevalence in the Australian population translates into a large increase in older people with a history of midlife obesity, with major implications for the future burden of disease in older persons.     

Size, frequency, and phylogenetic signal of multiple-residue indels in sequence alignment of introns

Indels in DNA sequences frequently affect more than a single nucleotide, creating problems for alignment, character coding and phylogenetic analysis. However, the size and frequency of multiple‐residue indels is not usually tested, and with popular alignment packages their reconstruction is indirectly acheived by reducing the affine (gap extension) cost. We explored the length distribution of indels in intron sequences of the gene Mp20 by modifying the gap opening and gap extension costs. Given a “known” tree for the study group, global homology levels were greatest under low gap cost, with gap extension costs of roughly 0.4‐fold the opening cost. Different approaches to gap coding and weighting suggested that taxonomic congruence was correlated with high frequencies of multiple‐position indels, with a maximum indel length of 2–5 bp and few indels above 15 bp, but also including a proportion of indels > 100 bp. Only a small minority of indels could be reconstructed as single‐position indels. Consequently, tree topologies improved when homologous multinucleotide indels were recoded as binary characters which are otherwise highly homoplastic and weighted characters in single‐position coding. In tree‐generating alignment procedures as implemented in POY, where gap penalty determines the character weight during tree search, the problem of assigning inappropriately high weight to multiple‐residue indels could partly be overcome by setting the extension costs to about 0.4‐fold lower than gap opening costs. We conclude that multiple consecutive gap positions are not independent characters and hence methods for parsimony reconstruction of long indels are required. Finally, we also observed a general lack of correlation between taxonomic and character congruence, demonstrating the difficulties of applying congruence criteria to decide among competing alignments. This highlights the value of recent model‐based alignment procedures which can implement the statistical distributions of indel size classes, and do not rely on potentially circular strategies for optimizing overall congruence. © The Willi Hennig Society 2006.     

New insights into the phylogenetics and biogeography of Arum (Araceae): unravelling its evolutionary history

The heat‐ and odour‐producing genus Arum (Araceae) has interested scientists for centuries. This long‐term interest has allowed a deep knowledge of some complex processes, such as the physiology and dynamics of its characteristic lure‐and‐trap pollination system, to be built up. However, mainly because of its large distributional range and high degree of morphological variation, species' limits and relationships are still under discussion. Today, the genus comprises 28 species subdivided into two subgenera, two sections and six subsections. In this study, the phylogeny of the genus is inferred on the basis of four plastid regions, and the evolution of several morphological characters is investigated. Our phylogenetic hypothesis is not in agreement with the current infrageneric classification of the genus and challenges the monophyly of several species. This demonstrates the need for a new infrageneric classification based on characters reflecting the evolution of this enigmatic genus. To investigate the biogeography of Arum deeply, further spatiotemporal analyses were performed, addressing the importance of the Mediterranean basin in the diversification of Arum. Our results suggest that its centre of origin was the European–Aegean region, and that major diversification happened during the last 10 Myr. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 163 , 14–32.     

A combined evidence phylogenetic analysis of Anguimorpha (Reptilia: Squamata)

Anguimorpha is a clade of limbed and limbless squamates with ca. 196 extant species and a known fossil record spanning the past 130 million years. Morphology‐based and molecule‐based phylogenetic analyses disagree on several key points. The analyses differ consistently in the placements of monstersaurs (e.g. Gila Monsters), shinisaurs (Crocodile Lizards), the anguid Anniella (American Legless Lizards), carusioids (Knobby Lizards), and the major clades within Varanus (Monitor Lizards). Given different data sources with such different phylogenetic hypotheses, Anguimorpha is an excellent candidate for a combined phylogenetic analysis. We constructed a data matrix consisting of 175 fossil and extant anguimorphs, and 2281 parsimony‐informative characters (315 morphological characters and 1969 molecular characters). We analysed these data using the computer program TNT using the “new technology search” with the ratchet. Our result is novel and shows similarities with both morphological and molecular trees, but is identical to neither. We find that a global combined evidence analysis (GCA) does not recover a holophyletic Varanoidea, but omission of fossil taxa reveals cryptic molecular support for that group. We describe these results and others from global morphological analysis, extant‐only morphological analysis, molecular data‐only analyses, combined evidence analysis of extant taxa, and GCA. © The Willi Hennig Society 2010.     

Recovering phylogenetic signal from frog mating calls

Goicoechea, N., De La Riva, I. & Padial, J. M. (2010). Recovering phylogenetic signal from frog mating calls. —Zoologica Scripta, 39, 411–154. Few studies have tried to analyse the phylogenetic information contained in frog mating calls. While some of those studies suggest that sexual selection deletes any phylogenetic signal, others indicate that frog calls do retain phylogenetic informative characters. Discordant results can be the outcome of disparate rates of character evolution and evolutionary plasticity of call characters in different groups of frogs, but also the result of applying different coding methods. No study to date has compared the relative performance of different coding methods in detecting phylogenetic signal in calls, hampering thus potential consilience between previous results. In this study, we analyse the strength of phylogenetic signal in 10 mating call characters of 11 related species of frogs belonging to three genera of Andean and Amazonian frogs (Anura: Terrarana: Strabomantidae). We use six quantitative characters (number of notes per call, note length, call length, number of pulses per note, fundamental frequency and dominant frequency) and four qualitative ones (presence/absence of: pseudopulses, frequency modulation in notes, amplitude modulation in notes and amplitude modulation in pulses). We code quantitative characters using four different coding and scaling methods: (i) gap‐coding, (ii) fixed‐scale, (iii) step‐matrix gap‐weighting with between‐characters scaling, and (iv) step‐matrix gap‐weighting with between‐states scaling. All four coding methods indicate that frog calls contain phylogenetic information. These results suggest that divergent selection on frog mating calls may not always be strong enough to eliminate phylogenetic signal. However, coding methods strongly affect the amount of recoverable information. Step‐matrix gap‐weighting with between‐characters scaling and gap‐coding are suggested as the best methods available for coding quantitative characters of frog calls. Also, our results indicate that the arbitrariness in selecting character states and the method for scaling transitions weights, rather than the number of character states, is what potentially biases phylogenetic analyses with quantitative characters.     

Hind limb myology of the common hippopotamus,Hippopotamus amphibius (Artiodactyla: Hippopotamidae)

Based on morphological traits, hippos have traditionally been classified with pigs and peccaries in the suborder Suiformes. However, molecular data indicate that hippos and cetaceans are sister taxa. This study analyses muscle characters of the common hippo hind limb in order to clarify the phylogenetic relationships and functional anatomy of hippos. Several muscles responsible for propelling the body through water are robust and display extensive fusions, including mm. semimembranosus, semitendinosus, biceps femoris and gluteus superficialis. In addition, common hippos retain long flexor and extensor tendons for each digit, reflecting the fact that all four toes are weight‐bearing. These flexor tendons, together with the well‐developed intrinsic muscles of the pes, serve to adduct the digits, preventing splaying of the toes when walking on soft terrain. Lastly, common hippos retain a number of primitive features, including the presence of m. articularis coxae, a well‐developed m. obturator internus, superficialis and profundus tendons to all digits, mm. flexor digitorum brevis, abductor digiti V, lumbricalis IV, adductores digitorum II and V, and two mm. interossei per digit. Pygmy hippos share these features. Thus, hippopotamids retain muscles that have been lost in the majority of artiodactyls, including other suiforms. These and previously reported findings for the forelimb support the molecular data in indicating an early divergence of the Hippopotamidae from the rest of the Artiodactyla. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 158 , 661–682.     

Phylogenetic inference using non‐redundant coding of dependent characters versus alternative approaches for protein‐coding genes

Contemporary molecular phylogenetic analyses often encompass a broad range of taxonomic diversity while maintaining high levels of sampling within each major taxon. To help maximize phylogenetic signal in such studies, one may analyse multiple levels of characters simultaneously. We test the performance of both the original and the modified versions of non‐redundant coding of dependent characters (NRCDC) relative to commonly applied alternative character‐sampling strategies using codon‐based simulations under a range of conditions. Both original and modified NRCDC generally outperformed other character‐sampling strategies that only sampled characters at one level (nucleotides or amino acids) over a broader range of simulation parameters than any of the alternative character‐sampling strategies with respect to both overall success of resolution and averaged overall success of resolution in the parsimony‐based analyses. Based on theoretical considerations and the results of our simulations, we encourage application and further testing of modified NRCDC in parsimony‐based molecular phylogenetic analyses that sample exons of protein‐coding genes. We expect that modified NRCDC will generally increase both accuracy and branch‐support over commonly applied alternative character‐sampling strategies when analysed using the same phylogenetic inference method, particularly in studies that sample both closely and distantly related taxa with clades representing both ancient and recent divergences. © The Willi Hennig Society 2010.     

Congruence,non‐homology,and the phylogeny of basal turtles

Joyce, W.G. and Sterli J. 2010. Congruence, non‐homology, and the phylogeny of basal turtles.–Acta Zoologica (Stockholm) Modern cladistic analysis is characterized by the assembly of increasingly larger data sets coupled with the use of congruence as the final test of homology. Some critics of this development have recently called for a return to more detailed primary homology analysis while questioning the utility of congruence. This discussion appears to be central to the debate regarding the phylogenetic relationships of basal turtles, as the large data sets developed by us have been criticized recently for utilizing poorly constructed characters and including too many homoplasy‐prone characters. Our analysis of this critique reveals that (1) new information regarding poorly understood taxa has a greater impact on the outcome of turtle phylogenies than the characters under dispute; (2) most current turtle phylogenies differ in taxon sampling, not character sampling, and so it appears illogical to condemn a particular analysis for its character sampling; (3) even evolutionary taxonomists should agree that key characters utilized to resolve basal turtle relationships cannot be thought to be ‘infallible’; (4) whereas various criteria provide positive evidence for homology, only congruence provides positive evidence for non‐homology; and (5) a stalemate between conflicting camps within a congruence frame work is preferable to the ad hoc dismissal of data sets, because authoritative statements are untestable.     

Delimiting baridine weevil evolution (Coleoptera: Curculionidae: Baridinae)

Since the erection of the weevil subfamily Baridinae by Schönherr in 1836, no phylogenetic hypothesis using cladistic methods has been proposed for this extraordinarily diverse group. This study provides the first hypothesis for the evolution of Baridinae using phylogenetic methods, including 301 taxa and 113 morphological characters. Despite fairly well‐resolved results, indicating paraphyly of nearly all of the currently recognized intrasubfamilial divisions, no change to the current classification is made. Even though groupings are proposed based on the final results, it is believed that more rigorous analyses need to be made prior to a re‐evaluation and subsequent alteration of the current classification. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010.     

Reproductive histology of Tomeurus gracilis Eigenmann, 1909 (Teleostei: Atherinomorpha: Poeciliidae) with comments on evolution of viviparity in atherinomorph fishes

Tomeurus gracilis is a species long considered pivotal in understanding the evolution of livebearing in atherinomorph fishes. Tomeurus gracilis is a zygoparous or embryoparous poeciliid: internal fertilization is followed by females laying fertilized eggs singly or retaining fertilized eggs until or near hatching. Tomeurus was hypothesized as the sister group of the viviparous poeciliids until it was proposed as a close relative of a derived viviparous poeciliid, Cnesterodon, hence nested among viviparous taxa rather than near the root of the tree. Here, we describe and compare reproductive morphological characters of the little‐known Tomeurus with those of representative atherinomorphs. In Tomeurus and Cnesterodon, sperm are packaged in naked sperm bundles, or spermatozeugmata, in a configuration considered here diagnostic of viviparous poeciliids. Testes are single and free sperm are stored in the ovary in both taxa in contrast to oviparous atherinomorphs in which testes are paired and sperm are not packaged and not stored in the ovary. Efferent ducts in Cnesterodon testes and other viviparous poeciliids have a PAS‐positive secretion demonstrating presence of a glycoprotein that inactivates sperm or prevents final sperm maturation. No PAS‐positive staining secretion was observed in Tomeurus or oviparous atherinomorphs. Tomeurus shares apomorphic reproductive characters, such as sperm bundle and testis morphology and a gonopodium, with viviparous poeciliids and plesiomorphic characters, such as a thick zona pellucida with filaments, with oviparous taxa. We do not postulate loss or reversal of viviparity in Tomeurus, and we corroborate its phylogenetic position as sister to the viviparous poeciliids. J. Morphol., 2010. © 2010 Wiley‐Liss, Inc.     

Towards a phylogeny of the flesh flies (Diptera: Sarcophagidae): morphology and phylogenetic implications of the acrophallus in the subfamily Sarcophaginae

The morphology of the acrophallus, the distal portion of the male phallus carrying the phallotreme, was studied in 72 exemplar species representing 56 genera and subgenera of the flesh fly subfamily Sarcophaginae. For 42 of those species, scanning electron microscopy was used to clarify the phallic morphology. Terms used to describe the male genitalia were updated based on new interpretations of homology. Male genitalic characters, combined with other morphological characters of adult males and females and of larvae, were used to construct a phylogeny. The monophyly of the subfamily was supported, and some generic‐level sister‐group relationships proposed in the literature, but without previous cladistic analyses, were also supported. The genus Blaesoxipha Loew, as currently recognized, was not monophyletic in our analysis. The genus Helicobia Coquillett is synonymized with Sarcophaga Meigen syn. nov. and treated as a subgenus of the latter. The Sarcophaga subgenera Neobellieria Blanchard and Mehria Enderlein were not monophyletic. Many of the clades in the analysis were supported primarily or exclusively by male genitalic character states, highlighting the importance of the male genitalia as a source of morphological characters for sarcophagine phylogeny. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 158 , 740–778.     

Depolarization of the membrane potential by hyaluronan

The membrane potential is mainly maintained by the K⁺ concentration gradient across the cell membrane between the cytosol and the extracellular matrix. Here, we show that extracellular addition of high‐molecular weight hyaluronan depolarized the membrane potential of human fibroblasts, human embryonic kidney cells (HEK), and central nervous system neurons in a concentration‐dependent manner, whereas digestion of cell surface hyaluronan by hyaluronidase caused hyperpolarization. This effect could not be achieved by other glycosaminoglycans or hyaluronan oligosaccharides, chondroitin sulfate, and heparin which did not affect the membrane potential. Mixtures of high‐molecular weight hyaluronan and bovine serum albumin had a larger depolarization effect than expected as the sum of both individual components. The different behavior of high‐molecular weight hyaluronan versus hyaluronan oligosaccharides and other glycosaminoglycans can be explained by a Donnan effect combined with a steric exclusion of other molecules from the water solvated chains of high‐molecular weight hyaluronan. Depolarization of the plasma membrane by hyaluronan represents an additional pathway of signal transduction to the classical CD44 signal transduction pathway, which links the extracellular matrix to intracellular metabolism. J. Cell. Biochem. 111: 858–864, 2010. © 2010 Wiley‐Liss, Inc.     

陕北谷子品种更替过程中产量及农艺性状的演变

选择不同年代(1960s—1970s、1980s—1990s、2000s—2010s)在陕北种植的6个谷子品种为试验材料,于2018—2019年在陕西榆林进行田间试验,研究分析了不同年代品种谷子产量及其农艺性状的演变特征。结果表明: 随年代更替,谷子品种产量呈现明显增加趋势,2000s—2010s选育的品种平均产量分别为0.46(2018)和0.66 kg·m^-2(2019),较2000s前的品种显著增产,增产幅度22%～53%;株高、穗重、叶重和杆重与产量趋势类似;而千粒重和穗长表现相对稳定,随品种更替并未呈现明显变化;旗叶宽度虽然变幅不大,但随品种更替呈明显增大趋势。相关性分析表明,穗重、杆重、叶重和株高与产量之间呈极显著相关。主成分分析显示,2000s—2010s谷子品种具有更大的优势。陕北谷子品种更替过程中主要通过株高和穗重的改良来增加单位面积产量,未来谷子高产育种应注重株高、穗重、杆重和叶重性状改良,尤其应探索适合机械收割的最优株高。     

Length–weight relationships of 14 coastal fish species from Punta del Diablo (Rocha,Uruguay)

This study provides information on length‐weight relationships for 14 marine fish species. Specimens were collected between 2006 and 2010 from the Uruguayan coastal zone (depth < 15 m) in Punta del Diablo, Rocha during a biodiversity monitoring program. This study represents the first reference on length‐weight relationships for two endangered Rajidae species and confirms the presence of the Stellifer rastrifer, whose distribution range has been extended southwards recently.     

Length‐weight relationships of Turcinoemacheilus kosswigi Bănărescu and Nalbant, 1964 (Teleostei:Nemacheilidae) in southwestern Iran and its relation to habitat structure

Length‐weight relationships of Turcinoemacheilus kosswigi, based on 56 individuals from two newly discovered localities in the Iranian Tigris drainage, are reported for the first time. These new localities have the same structural characters as already‐reported habitats, but the species was found in much higher altitudes than before.     

Priority effects among young‐of‐the‐year fish: reduced growth of bluegill sunfish (Lepomis macrochirus) caused by yellow perch (Perca flavescens)?

1. When available, Daphnia spp. are often preferred by age‐0 yellow perch and bluegill sunfish because of energetic profitability. We hypothesised that predation by age‐0 yellow perch could lead to a midsummer decline (MSD) of Daphnia spp. and that priority effects may favour yellow perch because they hatch before bluegill, allowing them to capitalise on Daphnia spp. prior to bluegill emergence. 2. Data were collected from 2004 to 2010 in Pelican Lake, Nebraska, U.S.A. The lake experienced a prolonged MSD in all but 1 year (2005), generally occurring within the first 2 weeks of June except in 2008 and 2010 when it occurred at the end of June. MSD timing is not solely related to seasonal patterns of age‐0 yellow perch consumption. Nevertheless, when Daphnia spp. biomass was low during 2004 and 2006–2010 (<4 mg wet weight L^?1), predation by age‐0 yellow perch seems to have suppressed Daphnia spp. biomass (i.e. <1.0 mg wet weight L^?1). The exception was 2005 when age‐0 yellow perch were absent. 3. Growth of age‐0 bluegill was significantly faster in 2005, when Daphnia spp. were available in greater densities (>4 mg wet weight L^?1) compared with the other years (<0.2 mg wet weight L^?1). 4. We conclude that age‐0 yellow perch are capable of reducing Daphnia biomass prior to the arrival of age‐0 bluegill, ultimately slowing bluegill growth. Thus, priority effects favour age‐0 yellow perch when competing with age‐0 bluegill for Daphnia. However, these effects may be minimised if there is a shorter time between hatching of the two species, higher Daphnia spp. densities or lower age‐0 yellow perch densities.