Species richness estimates of Blattodea s.s. (Insecta: Dictyoptera) from northern Guyana vary depending upon methods of species delimitation

Cockroaches (Order: Blattodea) comprise a taxon that, although very abundant in tropical forests, remains largely unstudied. Making sense of the diversity of species is a challenging task hindered by the large numbers of species and the abundance of cryptic or polymorphic forms. Here, we estimated species richness of cockroaches (s.s.) from northern Guyana while applying a method to deal with these confounding factors. We utilized two interpretations of abundance data, the first using only morphological information, and the second using both morphological and genetic barcode information. The two methods of species delimitation greatly influenced the resulting estimates of species richness. When incorporating genetic barcodes, our total species richness estimate decreased by 26%. Our results emphasize the importance of using independent datasets to delimit species boundaries and expert identification of specimens when possible.     

Female polymorphism, condition differences, and variation in male harassment and ambient temperature

Female polymorphism is considered to be maintained through negative frequency-dependent selection imposed by costly male harassment. However, few studies have questioned whether male harassment negatively affects female morph success and does so differently for female morphs, especially in the wild. In the present study, we quantified female morph condition (relative body mass and energy reserves) for a colour polymorphic damselfly under natural conditions and evaluated these measures against variation in proxies of male harassment (population density and operational sex ratio) and ambient temperature. Differences in protein content between female morphs were detected and the variation in condition could partly be explained from concomitant variation in proxies of male harassment. Specifically, the relationship between protein content and operational sex ratio differed between morphs in that the negative effect of male harassment was more pronounced in gynomorphs than in andromorphs. In addition, ambient temperature affected the body mass and protein content of female morphs differently, with andromorphs having higher condition values in favourable weather conditions, whereas, for gynomorphs, the patterns tended to be opposite. In conclusion, the results obtained in the present study suggest that male harassment negatively and differentially affects female morph success. Future studies should aim to elucidate whether the observed effects of ambient temperature contribute to the maintenance of the polymorphism.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 97 , 545–554.     

Evolutionary history of the complex polymorphic dobsonfly genus Neoneuromus (Megaloptera: Corydalidae)

The dobsonfly genus Neoneuromus van der Weele is endemic to the Oriental region. Species possess highly variable body and wing colouration and markings, not only among species but also among conspecific individuals of certain species. This stark polymorphism hinders accurate species identification, and obscures an undocumented species diversity as well as our understanding of the evolutionary history of this genus. We used multiple methods of molecular identification combined with morphological evidence to delimitate species, circumscribing a total of 13 species in Neoneuromus . Five new species are herein described: Neoneuromus indistinctus Liu, Hayashi & Yang, sp.n. , Neoneuromus maculatus Liu, Hayashi & Yang, sp.n. , Neoneuromus niger Liu, Hayashi & Yang, sp.n. , Neoneuromus similis Liu, Hayashi & Yang, sp.n. and Neoneuromus vanderweelei Liu, Hayashi & Yang, sp.n. The dated phylogeny with reconstructed ancestral areas indicates an initial divergence of Neoneuromus during the mid‐Eocene. A broad area including northeastern India and northern Indochina could be a centre for early divergence of the genus, while complex dispersal and vicariance events dating from the late Eocene to the Pliocene probably shaped the present diversity and distribution of the genus. Our ancestral character state reconstruction suggests that the pale and dark colour forms among different species, or conspecifics, could evolve rapidly and that changes in colouration could be driven by species‐specific mate recognition.     

Resource discovery in ant communities: do food type and quantity matter?

1. Omnivorous woodland ant species trade off between the ability to find and behaviourally control food resources. Dominant species can limit the ability of subordinates to harvest certain food items. However, subordinate species, by being faster discoverers, could gain access to such food items by arriving at them first. 2. In this study, we tested the hypothesis that resource‐directed discovery occurs in ant communities and that good discoverers preferentially discover high value resources. We did this by measuring time to discovery and the number of discoveries of high and low levels of two resource types, crickets and honey, for species occurring in Texas and Arizona woodland ant communities. 3. Ants discovered resources roughly 10 times faster in Texas than in Arizona. They discovered crickets more rapidly than honey in both communities, but there was no difference in the discovery of different resource levels. We also found that species were not biased in their discovery of different resource types or levels. 4. These results provide indirect evidence that discovery is directed by resource stimuli but that such directedness does not impact interspecific exploitative competition.     

A Large‐Scale SNP‐Based Genomic Admixture Analysis of the Captive Rhesus Macaque Colony at the California National Primate Research Center

Some breeding facilities in the United States have crossbred Chinese and Indian rhesus macaque (Macaca mulatta) founders either purposefully or inadvertently. Genetic variation that reflects geographic origins among research subjects has the potential to influence experimental outcomes. The use of animals from different geographic regions, their hybrids, and animals of varying degrees of kinship in an experiment can obscure treatment effects under study because high interanimal genetic variance can increase phenotypic variance among the research subjects. The intent of this study, based on a broad genomic analysis of 2,808 single nucleotide polymorphisms (SNPs), is to ensure that only animals estimated to be of pure Indian or Chinese ancestry, based on both demographic and genetic information, are used as sources of infants for derivation and expansion of the California National Primate Research Center's (CNPRC) super‐Specific Pathogen Free (SSPF) rhesus macaque colony. Studies of short tandem repeats (STRs) in Indian and Chinese rhesus macaques have reported that heterozygosity of STRs is higher in Chinese rhesus macaques than in Indian rhesus macaques. The present study shows that heterozygosity of SNPs is actually higher in Indian than in Chinese rhesus macaques and that the Chinese SSPF rhesus macaque colony is far less differentiated from their founders compared to the Indian‐origin animals. The results also reveal no evidence of recent gene flow from long‐tailed and pig‐tailed macaques into the source populations of the SSPF rhesus macaques. This study indicates that many of the long‐tailed macaques held in the CNPRC are closely related individuals. Most polymorphisms shared among the captive rhesus, long‐tailed, and pig‐tailed macaques likely predate the divergence among these groups. Am. J. Primatol. 74:747‐757, 2012. © 2012 Wiley Periodicals, Inc.