Genetic population structure and relatedness in the narrow‐striped mongoose (Mungotictis decemlineata), a social Malagasy carnivore with sexual segregation

Information on the genetic structure of animal populations can allow inferences about mechanisms shaping their social organization, dispersal, and mating system. The mongooses (Herpestidae) include some of the best‐studied mammalian systems in this respect, but much less is known about their closest relatives, the Malagasy carnivores (Eupleridae), even though some of them exhibit unusual association patterns. We investigated the genetic structure of the Malagasy narrow‐striped mongoose (Mungotictis decemlineata), a small forest‐dwelling gregarious carnivore exhibiting sexual segregation. Based on mtDNA and microsatellite analyses, we determined population‐wide haplotype structure and sex‐specific and within‐group relatedness. Furthermore, we analyzed parentage and sibship relationships and the level of reproductive skew. We found a matrilinear population structure, with several neighboring female units sharing identical haplotypes. Within‐group female relatedness was significantly higher than expected by chance in the majority of units. Haplotype diversity of males was significantly higher than in females, indicating male‐biased dispersal. Relatedness within the majority of male associations did not differ from random, not proving any kin‐directed benefits of male sociality in this case. We found indications for a mildly promiscuous mating system without monopolization of females by males, and low levels of reproductive skew in both sexes based on parentages of emergent young. Low relatedness within breeding pairs confirmed immigration by males and suggested similarities with patterns in social mongooses, providing a starting point for further investigations of mate choice and female control of reproduction and the connected behavioral mechanisms. Our study contributes to the understanding of the determinants of male sociality in carnivores as well as the mechanisms of female competition in species with small social units.     

Postovipositional development of the sand snake Psammophis sibilans (Serpentes:Lamprophiidae) in comparison with other snake species

Characterizing and comparing developmental progress across different species helps to interpret how different or similar body forms evolved. We present an embryonic table for the oviparous African Sand Snake Psammophis sibilans from the Lamprophidae family, describing its postovipositional in ovo development. Psammophis is a good model of a genus that is widely distributed in Africa and Asia and includes 22 species. We describe ten embryonic stages based on the development of externally visible morphological characteristics such as; pharyngeal arches, facial processes, eyes, scales, body pigmentation and body colour pattern development. This study discusses the development of this snake and compares it with that of the closely related brown house snake Lamprophis fulliginosus (Lamprophidae) and the medically important venomous cobras Naja haje haje and Naja kaouthia from the sister lineage Elapidae. The distantly related basal snake Python sebae, which displays different morphology and behaviour, was chosen for deeper insight into the evolution of body structures within the snake clade. We found interspecific differences in the relative stage of development of embryonic structures at the time of oviposition and during postovipositional embryonic development. One of the outcomes of this study is that embryonic structures such as the pharyngeal processes, eye pigmentation and scales are interspecifically conservative in regard to timing of morphodifferentiation, while body pigmentation, colour and colour pattern are interspecifically plastic in their temporospatial development.     

Craniodental body mass estimators in the dwarf bushbaby (Galagoides)

This study reports data on 17 craniodental body mass estimators in a sample (n = 38) of dwarf galagos (Galagoides). Correlation coefficients (r) range from a high of 0.64 for bizygomatic breadth and body mass to a low of 0.10 for M(3) length and body mass. Of the 17 variables studied, 7 exhibit significant (P < 0.05) correlation coefficients, with 5 of the 7 being multitooth (i.e., tooth row) or cranial variables. In contrast to the correlation coefficients of greater than 0.90 (e.g., Martin [1980] Z Morphol Anthropol 71:115-124; Steudel [1981] Int J Primatol 2:81-90; Gingerich et al. [1982] Am J Phys Anthropol 58:81-100; Conroy [1987] Int J Primatol 8:115-137) published for higher taxonomic level analyses (i.e., all-primate or prosimian) for many of the same variables studied here, the current data indicate weaker relationships when analyzed at the generic level. Possible explanations for the contrast in correlation coefficients between the current and many previous studies include the following: 1) individual variation due to a geographically dispersed sample, 2) individual body mass fluctuations due to seasonal food availability, and 3) individual variation within the sample due to variation in life-history parameters. Because the overall size range of the individuals in a specific or generic level analysis is smaller than that in an ordinal or subordinal sample, the individual variation normally masked when using species means represents a larger proportion of the total variation in a more limited sample. This may then be a cause of these weaker correlations.     

Genome sizes of three species in the subtribe Carabina (Coleoptera: Carabidae)

Genome sizes of three species in the subtribe Carabina (Coleoptera: Carabidae: tribe Carabini) were estimated from nuclei of spermatozoa using a flow cytometry. The estimated haploid genome sizes were about 330 megabases (Mb) for Damaster blaptoides, about 280 Mb for Carabus uenoi and about 260 Mb for Carabus yamato.     

Foraging ecology and niche overlap in pygmy (Kogia breviceps) and dwarf (Kogia sima) sperm whales from waters of the U.S. mid‐Atlantic coast

A complementary approach of stomach content and stable isotope analyses was used to characterize the foraging ecology and evaluate niche overlap between pygmy (Kogia breviceps) and dwarf (K. sima) sperm whales stranded on the U.S. mid‐Atlantic coast between 1998 and 2011. Food habits analysis demonstrated both species were primarily teuthophagous, with 35 species of cephalopods, and 2 species of mesopelagic fishes represented in their overall diets. Pianka's Index of niche overlap suggested high overlap between whale diets (O_n = 0.92), with squids from the families Histioteuthidae, Cranchidae, and Ommastrephidae serving as primary prey. Pygmy sperm whales consumed slightly larger prey sizes (mean mantle length [ML] = 10.8 cm) than dwarf sperm whales (mean ML = 7.8 cm). Mean prey sizes consumed by pygmy sperm whales increased with growth, but showed no trend in dwarf sperm whales. Significant differences were not detected in δ¹⁵N and δ¹³C values of muscle tissues from pygmy (10.8‰ ± 0.5‰, ?17.1‰ ± 0.6‰), and dwarf sperm whales (10.7‰ ± 0.5‰, ?17.0‰ ± 0.4‰), respectively. Isotopic niche widths also did not differ significantly and dietary overlap was high between the two species. Results suggest the feeding ecologies of the pygmy and dwarf sperm whales are similar and both species occupy equivalent trophic niches in the region.     

Identification and molecular mapping of indica high‐tillering dwarf mutant htd4, a mild phenotype allelic mutant of D14 in rice (Oryza sativa L.)

• Metabolism of strigolactones (SLs) can improve the efficiency of nutrient use by regulating the development of roots and shoots in crops, making them an important research focus for molecular breeding. However, as a very important plant hormone, the molecular mechanism of SL signal transduction still remains largely unknown.
• In this study, we isolated an indica high‐tillering dwarf mutant 4 (htd4), a spontaneous mutant of rice, from the restorer line Gui99.
• Mapping and sequencing analysis showed that htd4 was a novel allelic mutant of D14, in which a single base substitution forms a premature termination codon. Quantitative RT‐PCR analyses revealed that expression levels of the genes D10, D17, D27, D3 and D14 increased significantly, while expression of D53 decreased in htd4, compared with the wild type. A subcellular localisation assay showed that the mutant of D14 in htd4 did not disturb the normal localisation of D14 proteins. However, a BiFC assay suggested that the mutant‐type D14 could not interact with D3. Additionally, compared with other D14 allelic mutants, htd4 was the first mutant of D14 discovered in indica, and the differences in many yield traits such as plant height, seed‐setting rate and grain sizes between htd4 and the wild type were less than those between other D14 allelic mutants and the wild type.
• Therefore, htd4 is considered a mild phenotype allelic mutant of D14. We conclude that the absence of functional D14 caused the high‐tillering dwarf phenotype of htd4. Our results may provide vital information for research on D14 function and the application of htd4 in molecular breeding.

     

Hybridization and introgression among three Aconitum (Ranunculaceae) species of different ploidy levels in the Tatra Mountains (Western Carpathians)

Hybridization among species of A conitum effects their morphology and ecology. In this study the hybridization between the diploid 2n(2x) = 16 ( A . lasiocarpum and A . variegatum) and tetraploid 2n(4x) = 32 ( A . firmum) species was documented in the Tatra Mountains (Western Carpathians) in a small, local population in a semi‐natural site. The hybrid species were: homoploid A . × pawlowskii ( A . lasiocarpum × A . variegatum), and triploid A . × berdaui ( A . firmum × A . variegatum, 2n(3x) = 24). Chloroplast DNA (cpDNA) alleles formed two distinct haplotypes, one typical for the tetraploid and another for diploid lines, shared between the tetraploid, triploid and diploid groups, indicating introgressive hybridization. The presumed gene flow was from the tetraploid to diploid species via the triploid bridge. The only two specimens of A . × pawlowskii that harbored tetraploid ( A . firmum) type cpDNA possessed bracteoles of A . firmum‐type. The remaining introgressed (cpDNA and Inter Simple Sequence Repeats (ISSR)) specimens ( A . variegatum) were morphologically pure, implying cryptic introgression. ISSR loci shared between the tetraploid A . firmum and diploid A . variegatum support the hypothesis of an ancient allopolyploid origin of A . firmum and the diploid species of A . variegatum‐type as one of its parent.     

A diverse chasmataspidid (Arthropoda: Chelicerata) fauna from the Early Devonian (Lochkovian) of Siberia

Examination of material held at the Palaeontological Institute, Moscow, enables the identification of two novel chasmataspidid species: Nahlyostaspis bergstroemi gen. et sp. nov. and Skrytyaspis andersoni gen. et sp. nov. ‘Eurypterus’ stoermeri and ‘Tylopterella’ menneri are both redescribed as chasmataspidids, having previously been assigned to Eurypterida. ‘T’. menneri is transferred to the new genus Dvulikiaspis gen. nov. An identical prosomal structure is identified in ‘Eurypterus’ stoermeri and Heteroaspis novojilovi from the Devonian of Germany and the two species are synonymized, with ‘E’ stoermeri having priority. The previous synonymy of H. novojilovi with Diploaspis casteri is rejected. The presence of ophthalmic ridges is confirmed within Diploaspididae, and new structural characteristics of their bucklers are identified.     

The embryonic development of the Egyptian cobra Naja h. haje (Squamata: Serpentes: Elapidae)

The Egyptian cobra, Naja h. haje, is the largest of the African cobras and is a member of a successful and medically important species complex found throughout Africa, north and south of the Sahara, as well as across the Arabian Peninsula to Oman. Although its phylogenetic position and venom characteristics have been well studied, its development has not. Here, we present a normal staging table for N. h. haje, based on external features. Comparison with firstly the Asian monocled cobra, Naja kaouthia, and then with the small number of other oviparous snake species, allowed us to examine whether differences between two species in the same genus were of the same type and magnitude as those between unrelated genera. In fact, at least with respect to external features, we found a similar level of disparity. N. h. haje embryos lagged behind those of N. kaouthia in body and head scale development, size in ovo and hatchling length, despite having a slightly shorter incubation period and a somewhat larger adult size. Some of these differences may have been the result of differing incubation temperatures. Nonetheless, there does appear to be a broadly conserved pattern of in ovo development in at least macrostomatan snakes.     

Diversity and selective pressures of anticoagulants in three medicinal leeches (Hirudinida: Hirudinidae,Macrobdellidae)

Although medicinal leeches have long been used as treatment for various ailments because of their potent anticoagulation factors, neither the full diversity of salivary components that inhibit coagulation, nor the evolutionary selection acting on them has been thoroughly investigated. Here, we constructed expressed sequence tag libraries from salivary glands of two species of medicinal hirudinoid leeches, Hirudo verbana and Aliolimnatis fenestrata, and identified anticoagulant‐orthologs through BLASTx searches. The data set then was augmented by the addition of a previously constructed EST library from the macrobdelloid leech Macrobdella decora. The identified orthologs then were compared and contrasted with well‐characterized anticoagulants from a variety of leeches with different feeding habits, including non‐sanguivorous species. Moreover, four different statistical methods for predicting signatures of positive and negative evolutionary pressures were used for 10 rounds each to assess the level and type of selection acting on the molecules as a whole and on specific sites. In total, sequences showing putative BLASTx‐orthology with five and three anticoagulant‐families were recovered in the A. fenestrata and H. verbana EST libraries respectively. Selection pressure analyses predicted high levels of purifying selection across the anticoagulant diversity, although a few isolated sites showed signatures of positive selection. This study represents a first attempt at mapping the anticoagulant repertoires in a comparative fashion across several leech families.     

The relationship between cranial morphology,bite performance,diet and habitat in a radiation of dwarf chameleon (Bradypodion)

Many animals show unique morphological and behavioural adaptations to specific habitats. In particular, variation in cranial morphology is known to influence feeding performance, which in turn influences dietary habits and, ultimately, fitness. Dietary separation is an important means of partitioning ecological niches and avoiding inter‐ and intraspecific competition. Consequently, differences in dietary resources may help explain phenotypic divergence in closely‐related species occupying different habitats, as well as sexual dimorphism. We test this hypothesis on five phenotypic forms of a recent radiation of dwarf chameleons (Bradypodion) that vary extensively in habitat use and cranial morphology. By examining stomach contents, the dietary composition of each phenotypic form is compared to investigate potential differences in feeding strategies. Overall, chameleons in the present study exhibit considerable dietary overlap (at both inter‐ and intraspecific levels), indicating that diet is not a major driver of variation in cranial morphology within this radiation. However, the stomachs of closed‐canopy females were found to contain more prey items than male stomachs, possibly indicating that females require a greater caloric intake than their male counterparts.     

A comparison of pollinator fig wasp development in figs of Ficus montana and its hybrids with Ficus asperifolia

Figs (Moraceae) and pollinator fig wasps (Hymenoptera: Agaonidae) have a highly specific mutualistic relationship but fig wasps occasionally enter atypical hosts, and this can lead to hybrid fig trees and the potential for gene flow between species. Many fig trees are dioecious, with fig wasp offspring developing in galled ovules inside figs on male trees, whereas seeds develop only in figs on female trees. We generated experimental hybrids between the Asian Ficus montana Blume and a closely related African species Ficus asperifolia Miquel. Male F1s were sterile if entered by Kradibia tentacularis (Grandi) (Agaonidae), the pollinator of F. montana, because its offspring always failed to develop, without ovule enlargement. As with the F1s, figs on most male backcross plants [F. montana × (F. montana × F. asperifolia)] also aborted shortly after pollinator entry, resulting in a higher turnover of figs than with F. montana, although the times taken for the figs to reach receptivity were similar. Pollinator larvae nonetheless consistently managed to develop inside the figs of one backcross plant and also occasionally in a few figs from another backcross individual. In these figs, galled ovules developed as normal, whereas in figs that aborted the galled ovules failed to enlarge. The sex ratio of K. tentacularis progeny in the backcross figs was female biased and did not differ from that in F. montana figs. Sycoscapter spec. (Hymenoptera: Pteromalidae), a parasitoid of K. tentacularis, was able to lay eggs and developed normally inside male backcross figs where its host was present.     

Suitability assessment of three Trichogramma species in the control of Mythimna separata (Lepidoptera: Noctuidae)

Mythimna separata (Walker) is a serious cosmopolitan pest. Trichogramma species have been used worldwide as biological control agents of lepidopteran pests. However, no data on the control efficiency of Trichogramma species on this pest have been reported. We evaluated the suitability of M. separata eggs for three Trichogramma species, Trichogramma dendrolimi Matsumura, T. ostriniae Pang et Chen and T. japonicum Ashmead, and compared the suitability with that of Corcyra cephalonica (Stainton) eggs. The parasitism rate, development time, emergence rate, female proportion, body size and egg load of female offspring indicated that the M. separata egg is a suitable host for the three Trichogramma species. On the other hand, the non‐emergence rate and the relationship between egg load and body size reflected that M. separata eggs are less suitable for the three Trichogramma species than C. cephalonica eggs. Egg resorption occurred in T. japonicum 4 days after emergence.     

Colonization of islands in the Mona Passage by endemic dwarf geckoes (genus Sphaerodactylus) reconstructed with mitochondrial phylogeny

Little is known about the natural history of the Sphaerodactylus species endemic to the three islands located in the Mona Passage separating the Greater Antillean islands of Hispaniola and Puerto Rico. In this study, parts of two mitochondrial genes, 16S rRNA and 12S rRNA, were sequenced to determine the relationships between the sphaerodactylids that live in the Mona Passage and other Caribbean species from the same genus. While the main goal was to identify the biogeographical origin of these species, we also identified a genetically distinct type of dwarf gecko that warrants future evaluation as a possible new species. According to the reconstructed phylogenies, we propose a stepwise model of colonization wherein S. nicholsi from southwestern Puerto Rico or a very close ancestor gave rise through a founder event to Sphaerodactylus monensis on Mona Island. In a similar fashion, S. monensis or a very close ancestor on Mona Island gave rise to S. levinsi on Desecheo Island. This study also suggests that the most recent common ancestor between the species from the islands in the Mona Passage and Puerto Rico existed approximately 3 MYA.     

Contemporary effective population and metapopulation size (Ne and meta‐Ne): comparison among three salmonids inhabiting a fragmented system and differing in gene flow and its asymmetries

We estimated local and metapopulation effective sizes ( and meta‐) for three coexisting salmonid species (Salmo salar, Salvelinus fontinalis, Salvelinus alpinus) inhabiting a freshwater system comprising seven interconnected lakes. First, we hypothesized that might be inversely related to within‐species population divergence as reported in an earlier study (i.e., F_ST: S. salar> S. fontinalis> S. alpinus). Using the approximate Bayesian computation method implemented in ONeSAMP, we found significant differences in () between species, consistent with a hierarchy of adult population sizes (). Using another method based on a measure of linkage disequilibrium (LDNE: ), we found more finite values for S. salar than for the other two salmonids, in line with the results above that indicate that S. salar exhibits the lowest among the three species. Considering subpopulations as open to migration (i.e., removing putative immigrants) led to only marginal and non‐significant changes in , suggesting that migration may be at equilibrium between genetically similar sources. Second, we hypothesized that meta‐ might be significantly smaller than the sum of local s (null model) if gene flow is asymmetric, varies among subpopulations, and is driven by common landscape features such as waterfalls. One ‘bottom‐up’ or numerical approach that explicitly incorporates variable and asymmetric migration rates showed this very pattern, while a number of analytical models provided meta‐ estimates that were not significantly different from the null model or from each other. Our study of three species inhabiting a shared environment highlights the importance and utility of differentiating species‐specific and landscape effects, not only on dispersal but also in the demography of wild populations as assessed through local s and meta‐s and their relevance in ecology, evolution and conservation.     

Determination of vertebral heart score in three species of Spider monkey (Ateles fusciceps,A. hybridus and A. paniscus)

Background

The vertebral heart score (VHS) is a method of evaluation of cardiac size well documented in domestic mammals and in other primate species, and the aim of this study was to determine the VHS in three species of Spider monkey.

Methods

In this retrospective study, right lateral radiographs of thirty clinically well animals were reviewed and VHS determined. The species included were Ateles fusciceps (n=17), Ateles hybridus (n=8) and Ateles paniscus (n=5).

Results

The VHS was found to vary between species and was 9.73±0.81 for A. fusciceps, 10.53±0.37 for A. hybridus and 10.45±0.27 for A. paniscus.

Conclusions

The observed values appear consistent with values determined for other primate species. There was statistically significant variation noted between species, and so VHS should be considered species‐specific in this genus. The values determined may be of benefit in objectively evaluating cardiac size in the species investigated.     

Two‐component calls in short‐finned pilot whales (Globicephala macrorhynchus)

Short‐finned pilot whales (Globicephala macrorhynchus) have complex vocal repertoires that include calls with two time‐frequency contours known as two‐component calls. We attached digital acoustic recording tags (DTAGs) to 23 short‐finned pilot whales off Cape Hatteras, North Carolina, and assessed the similarity of two‐component calls within and among tags. Two‐component calls made up <3% of the total number of calls on 19 of the 23 tag records. For the remaining four tags, two‐component calls comprised 9%, 23%, 24%, and 57% of the total calls recorded. Measurements of six acoustic parameters for both the low and high frequency components of all two‐component calls from the five tags were compared using a generalized linear model. There were significant differences in the acoustic parameters of two‐component calls between tags, verifying that acoustic parameters were more similar for two‐component calls recorded on the same tag than for calls between tags. Spectrograms of all two‐component calls from the five tags were visually graded and independently categorized by five observers. A test of inter‐rater reliability showed substantial agreement, suggesting that each tag contained a predominant two‐component call type that was not shared across tags.