Historical and ecological correlates of body shape in the brook stickleback, Culaea inconstans

Using geometric morphometric methods, we evaluated the correlation between phenotypic variation and available historical and habitat information for two genetically differentiated, allopatric lineages of a widespread North American species, the brook stickleback ( Culaea inconstans ). The results obtained revealed strong patterns of structured phenotypic differentiation across the species range with extreme phenotypes occurring at the northwest and southeast range boundaries. Shape variation was broadly congruent with the distribution of two mitochondrial DNA lineages; a deep-bodied eastern form (Atlantic refugium) and a slim-bodied western form (Mississippian refugium); however, the two forms were not lineage-specific and phenotypic cladistic diversification is likely to be an artefact of underlying clinal variation associated with longitudinal and latitudinal gradients. In addition, we found little evidence of diagnosable lake and river forms across North America. Taken together, large-scale patterns of phenotypic diversity observed in C. inconstans suggest that relatively recent factors, such as continually varying natural selection across the range and/or potential local gene flow, may substantially mitigate the effects of historical separation or a generalized adaptive response to alternative habitats.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 96 , 769–783.     

Adaptation to host plants may prevent rapid insect responses to climate change

We must consider the role of multitrophic interactions when examining species' responses to climate change. Many plant species, particularly trees, are limited in their ability to shift their geographic ranges quickly under climate change. Consequently, for herbivorous insects, geographic mosaics of host plant specialization could prohibit range shifts and adaptation when insects become separated from suitable host plants. In this study, we examined larval growth and survival of an oak specialist butterfly (Erynnis propertius) on different oaks (Quercus spp.) that occur across its range to determine if individuals can switch host plants if they move into new areas under climate change. Individuals from Oregon and northern California, USA that feed on Q. garryana and Q. kelloggii in the field experienced increased mortality on Q. agrifolia, a southern species with low nutrient content. In contrast, populations from southern California that normally feed on Q. agrifolia performed well on Q. agrifolia and Q. garryana and poorly on the northern, high elevation Q. kelloggii. Therefore, colonization of southern E. propertius in higher elevations and some northern locales may be prohibited under climate change but latitudinal shifts to Q. garryana may be possible. Where shifts are precluded due to maladaptation to hosts, populations may not accrue warm‐adapted genotypes. Our study suggests that, when interacting species experience asynchronous range shifts, historical local adaptation may preclude populations from colonizing new locales under climate change.     

Dinucleotide microsatellite primers designed for a critically endangered primate,the black lion tamarin (Leontopithecus chrysopygus)

Black lion tamarin (BLT) monkeys (Leontopithecus chrysopygus) have suffered a severe reduction in their natural range and are consequently critically endangered. Because allozyme data showed very low levels of variation, it was not clear if these monkeys had much genetic diversity. We designed microsatellite primers for BLTs, and from them we identified nine polymorphic loci, seven of which were tested on golden lion tamarins (GLTs) (Leontopithecus rosalia). All of the seven polymorphic loci and two other monomorphic BLT loci were polymorphic in GLTs. The microsatellite markers identified here are directly applicable to ongoing lion tamarin population and conservation genetics studies.     

Characterization of 35 microsatellite loci in the Pacific lion‐paw scallop (Nodipecten subnodosus) and their cross‐species amplification in four other scallops of the Pectinidae family

Four microsatellite‐enriched DNA libraries yielded 35 microsatellite loci from 100 primer pairs designed for Pacific lion‐paw scallop, Nodipecten subnodosus. The number of alleles ranged from four to 28. Three of the 35 loci were not in Hardy–Weinberg equilibrium and linkage disequilibrium was found for one pair of loci. These microsatellites will be used to analyse the population structure of the species in Mexico's Baja Peninsula to propose management strategies for scallop aquaculture development. Twenty‐six primer pairs cross‐amplified in Nodipecten nodosus, whereas none (Argopecten ventricosus) or few cross‐amplified in the Argopecten species.     

Environmental context alters ecological trade‐offs controlling ant coexistence in a spatially heterogeneous region

1. Ecological trade‐offs in ant (Hymenoptera: Formicidae) assemblages and their implications for coexistence boast a rich history in entomology. Yet investigations of trade‐offs have largely been limited to homogeneous environments. We examined how environmental context modifies trade‐off expression in an ant assemblage spanning a heterogeneous region in central Florida, U.S.A. 2. We examined how trade‐off expression is altered among two contrasting habitat types: open shrub and forest. We tested for the presence of the dominance‐discovery trade‐off and two dominance‐thermal tolerance trade‐offs by estimating behavioral dominance, discovery ability, and thermal tolerance (foraging thermal limit, lethal temperature, and maximal abundance temperature) for a wide range of interacting ant species. 3. We found significantly linear dominance hierarchies in both shrub and forest habitats, showing dominant species out‐compete subordinates for food resources. In thermally stressful shrub habitats, subordinates exhibit higher thermal tolerances, take greater thermal risks, and reach maximum forager abundances at higher temperatures than do dominant species. This suggests temperature mediated trade‐offs control coexistence in shrub habitat. In thermally moderate forest habitat, we found limited evidence for trade‐offs between competitive dominance and resource discovery or between dominance and thermal traits, implying other processes control coexistence. These results demonstrate that trade‐offs controlling ant coexistence may be contingent on environmental context.     

Phylogeny,divergence times and biogeography of window flies (Scenopinidae) and the therevoid clade (Diptera: Asiloidea)

The evolution of the ‘therevoid’ clade, with an emphasis on window flies (Scenopinidae), is presented by combining DNA sequence data with morphological characters for living and fossil species. The therevoid clade represents a group of four families (Apsilocephalidae, Evocoidae, Scenopinidae and Therevidae) of lower brachyceran Diptera in the superfamily Asiloidea. A comprehensive phylogenetic analysis using parsimony and likelihood methods was undertaken using extensive taxon sampling from all families and subfamilies, and compared with outgroup taxa sampled from the related families Asilidae, Mydidae, Apioceridae and Empididae. Fifty‐nine morphological characters (adult, larval and pupal) were combined with 6.4 kb of DNA sequences for two ribosomal genes (16S and 18S ribosomal DNA) and three protein‐encoding genes [cytochrome oxidase I (COI), triose phosphate isomerase (TPI) and the CPSase region of carbamoyl‐phosphate synthase‐aspartate transcarbamoylase‐dihydroorotase (CAD)]. Results from combined analyses of morphological and molecular data for 78 taxa representing all families of the therevoid clade are presented. Specific hypotheses of the relationship between respective families and subfamilies were tested statistically using four‐cluster likelihood mapping. The therevoid clade is a well‐supported monophyletic group within Asiloidea, with Evocoidae sister to Apsilocephalidae and Therevidae sister to Scenopinidae. Temporal and zoogeographical aspects of therevoid clade evolution were investigated using Bayesian divergence time estimates and Lagrange ancestral range scenarios. The effect of inclusion of fossils as terminal taxa on phylogenetic and divergence time estimation was investigated, with morphological scoring for fossil representatives included in the analyses rather than used simply as minimum age constraints. In each analysis there was either improvement in estimation, or only marginal and localized loss in tree resolution, and with younger estimates of divergence time across the tree. The historical biogeography of the therevoid clade was examined with multiple trans‐Antarctic vicariance events between Australasia and South America evident during the Late Cretaceous to early Palaeogene. Scenopininae is newly subdivided into two tribes, Metatrichini trib.n. and Scenopinini Fallén stat.r. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:4974EBF8‐3117‐4189‐B6DE‐7D5BF9B23E53 .     

Single‐Nucleotide Polymorphisms Reveal Patterns of Allele Sharing Across the Species Boundary Between Rhesus (Macaca mulatta) and Cynomolgus (M. fascicularis) Macaques

Both phenotypic and genetic evidence for asymmetric hybridization between rhesus (Macaca mulatta) and cynomolgus (Macaca fascicularis) macaques has been observed in the region of Indochina where both species are sympatric. The large‐scale sharing of major histocompatibility complex (MHC) class II alleles between the two species in this region supports the hypothesis that genes, and especially genes involved in immune response, are being transferred across the species boundary. This differential introgression has important implications for the incorporation of cynomolgus macaques of unknown geographic origin in biomedical research protocols. Our study found that for 2,808 single‐nucleotide polymorphism (SNP) markers, the minor allele frequencies (MAF) and observed heterozygosity calculated from a sample of Vietnamese cynomolgus macaques was significantly different from those calculated from samples of both Chinese rhesus and Indonesian cynomolgus macaques. SNP alleles from Chinese rhesus macaques were overrepresented in a sample of Vietnamese cynomolgus macaques relative to their Indonesian conspecifics and located in genes functionally related to the primary immune system. These results suggest that Indochinese cynomolgus macaques represent a genetically and immunologically distinct entity from Indonesian cynomolgus macaques. Am. J. Primatol. 75:135‐144, 2013. © 2012 Wiley Periodicals, Inc.     

GENETIC ENGINEERING TO AVOID GENETIC NEGLECT: FROM CHANCE TO RESPONSIBILITY

Currently our assessment of whether someone is a good parent depends on the environmental inputs (or lack of such inputs) they give their children. But new genetic intervention technologies, to which we may soon have access, mean that how good a parent is will depend also on the genetic inputs they give their children. Each new piece of available technology threatens to open up another way that we can neglect our children. Our obligations to our children and our susceptibilities to corresponding legal and moral sanctions may be about to explosively increase. In this paper I argue that we should treat conventional neglect and ‘genetic neglect’– failing to use genetic intervention technologies to prevent serious diseases and disabilities – morally consistently. I conclude that in a range of cases parents will have a moral obligation to use genetic treatments to prevent serious disabilities in their children. My particular focus is on prenatal interventions and their impact of the bodily integrity of expectant mothers. I conclude that although bodily integrity constrains moral obligations, it is outweighed in a range of cases.