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The West Indies can be considered as a laboratory of biogeography and evolution, and the Caribbean Islands constitute one of the planet's biodiversity hotspots. Within the region, Cuba is the largest island and is crucial to gaining an understanding of the origin and evolutionary history of Caribbean flora and fauna. This paper provides an introduction to a Special Issue of the Biological Journal of the Linnean Society on current Cuban plant and animal biodiversity, with an emphasis on evolutionary biology and biogeography. The present issue includes 10 contributions and addresses a wide diversity of species and taxonomic groups, study levels, and research tools. This collection of articles not only provides an integrative vision of Cuba's biodiversity and the potential patterns and processes involved in its evolutionary history, but could also provide food for future research on its biodiversity from an evolutionary perspective. [ABSTRACT FROM AUTHOR]

The present paper describes three new species of freshwater flatworm of the genus Dugesia from Madagascar, by applying an integrative approach to taxonomy, combining morphological and molecular information. Further, molecular data uncovered a cryptic species diversity, enabling taxonomic assignment of several asexual populations to already known species and thus pointing to at least two more species of the genus Dugesia present on Madagascar. The paper redefines several character state conditions in species of Dugesia, relating to three types of accessory structures of the copulatory apparatus: penial annexes, atrial folds and valves, and adenodactyls. It also provides a more precise definition of character states concerning the course of the ejaculatory duct through the penis papilla. In order to be able to examine the taxonomic status, phylogenetic position and biogeography of the Malagasy Dugesia species, molecular phylogenetic analyses were performed on many populations from Madagascar and also on representatives of 27 species from across the geographic range of the genus. Our results show that Madagascar is not only rich in number of species but also in genetic diversity, thus highlighting that the biodiversity and endemicity of Malagasy freshwater planarians has been underestimated. [ABSTRACT FROM AUTHOR]

Although the Caribbean region is recognized as a major biodiversity hotspot, many megadiverse groups remain taxonomically understudied. The ornate spiders of the genus Spintharus Hentz, 1850 (Theridiidae, Araneae) are a good example where taxonomic boundaries have remained unclear. The genus shows profuse habitus and genitalic variation in the Caribbean and has distinct colour patterns that rapidly degrade in ethanol. The leading theridiid taxonomist of the last six decades (Herbert W. Levi) therefore concluded that the morphological diversity of Caribbean Spintharus was, with the evidence available at the time, best characterized as intraspecific variation. The first molecular study, however, rejected the 'single widespread species' hypothesis, rather indicating multiple short-range endemics. This paper describes and diagnoses 15 new species based on the combination of molecular and morphological data, including S. davidattenboroughi sp. nov., S. barackobamai sp. nov., S. michelleobamaae sp. nov., S. davidbowiei sp. nov., S. leonardodicaprioi sp. nov. and S. berniesandersi sp. nov. Much Caribbean diversity may be similarly 'hidden' by existing taxonomical hypotheses; clearly, more focus is needed on the taxonomy of megadiverse groups. The implications of integrated taxonomy dramatically alter conservation biology when a single widespread species is instead found to represent multiple short-range endemics. Our goal here is thus to update Spintharus taxonomy and discuss the implications of the newly found diversity for both biodiversity research and conservation. [ABSTRACT FROM AUTHOR]

It has been recognized for decades that animals sense light using photoreceptors besides those that are devoted strictly to vision. However, the nature of these receptors, their molecular components, their physiological responses, and their biological functions are often obscure. Only recently have researchers begun to learn how critical these non-visual or very simple visual responses are to organismal function. New approaches, including high-throughput molecular genetic techniques, have led to a revolution in our understanding of the evolution, anatomical distribution, physiology, and--in some cases--function of non-visual photoreception in diverse organisms. In the following papers, we bring together specialists from throughout the field to review the current state of knowledge regarding extraocular, non-visual, and simple photoreceptors in a large diversity of organisms ranging from protists through vertebrates and invertebrates. [ABSTRACT FROM AUTHOR]

Most species evolve within fluctuating environments, and have developed adaptations to meet the challenges posed by environmental heterogeneity. One such adaptation is phenotypic plasticity, or the ability of a single genotype to produce multiple environmentally-induced phenotypes. Yet, not all plasticity is adaptive. Despite the renewed interest in adaptive phenotypic plasticity and its consequences for evolution, much less is known about maladaptive plasticity. However, maladaptive plasticity is likely an important driver of phenotypic similarity among populations living in different environments. This paper traces four strategies for overcoming maladaptive plasticity that result in phenotypic similarity, two of which involve genetic changes (standing genetic variation, genetic compensation) and two of which do not (standing epigenetic variation, plastic compensation). Plastic compensation is defined as adaptive plasticity overcoming maladaptive plasticity. In particular, plastic compensation may increase the likelihood of genetic compensation by facilitating population persistence. We provide key terms to disentangle these aspects of phenotypic plasticity and introduce examples to reinforce the potential importance of plastic compensation for understanding evolutionary change. [ABSTRACT FROM AUTHOR]

The major histocompatibility complex (MHC) plays an important role in an organism's ability to respond to pathogens. Immunogenetic diversity is advantageous as it permits the recognition of more external antigens. For this reason, MHC and immune gene variation are considered a barometer for the genetic health of wild populations. Mountain goats (Oreamnos americanus) were previously shown to have little variation at the MHC Class II Oram-DRB locus, which was attributed to population bottlenecks during the last glacial maximum (LGM). In this paper, we extended the analysis of immunogenetic variability in mountain goats to 5 genes representing the 3 classes of MHC gene (Class I OLA, Class II DRA and DRB, and Class III TNF-α) and the natural resistance–associated macrophage protein. We sequenced approximately 3000 bp from 31 individuals sampled across the range of mountain goats and found very low levels of diversity (1–3 polymorphic sites per gene) with the exception of the Class I Oram-OLA gene. Oram-OLA was nearly 30 times more diverse than the other immune genes and appears to represent a source of increased immunogenetic diversity. This diversity may be attributed to multiple loci, mediated by pathogen exposure, or potentially influenced by social factors. The distribution of SNPs was not associated with refugial history, suggesting that the current distribution of immunogenetic diversity was present prior to the LGM. These data suggest that although they have low levels of diversity at the 4 of 5 immune loci, mountain goats may be better equipped for future climate oscillations and pathogen exposure than previously thought. [ABSTRACT FROM PUBLISHER]

The flower fly genus Citrogramma is revised here. Seventeen new species are described; four lectotypes and one neotype are designated; two species are transferred from Xanthogramma to Citrogramma; and another Xanthogramma species, Xanthogramma fasciatum, is synonymized under Citrogramma clarum. Xanthogramma indica and Xanthogramma pruthii are considered junior synonyms of Scaeva latimaculata. Redescriptions, illustrations, synonymies, diagnoses, and distributional data are given for all species of Citrogramma recognized here, and an identification key is also provided. New specimens and species from New Caledonia, Taiwan, Nepal, and China expand the geographical range of the genus. The large number of new species proposed in this paper highlights the prevailing incomplete knowledge of this genus. New Guinea has the highest diversity of known Citrogramma species. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 164, 99-172. [ABSTRACT FROM AUTHOR]

One of the simplest models of chromosomal speciation is speciation by monobrachial centric fusion. This model is based on the assumption that a sterility barrier can develop between populations, in which fixed centric fusions show monobrachial homology, i.e. share only one chromosome arm. However, studies aimed at delineating intermediate stages of transition to reproductive isolation are lacking. In this paper, we describe a new area of chromosomal polymorphism in the house mouse, Mus musculus domesticus Schwarz and Schwarx, 1943, in Sicily (Italy). We trapped 79 mice at eighteen localities in an area of approximately 500 Km surrounding the largest active European volcano, Mount Etna. Combining G-banding and chromosome painting we identified twelve different Robertsonian (Rb) metacentrics. Considering the high number of Rb fusions, some of them shared with other documented areas, the presently studied area of chromosomal polymorphism is very likely to represent a mixture of allochthonous and autochthonous Rb fusions. The Rb(9.16) is the most widespread metacentric (overall frequency 0.80). Two Rb metacentrics, Rb(4.10) and Rb(5.6), have similar overall frequency, 0.29 and 0.37, respectively, and are narrowly co-distributed in ten populations. Nine fusions - Rb(2.13), Rb(1.3), Rb(12.17), Rb(8.17), Rb(2.14), Rb(10.14), Rb(11.17), Rb(3.15), and Rb(11.14) - show a low frequency (0.04-0.01) and mostly non-overlapping localization, but each of them shares monobrachial homology with at least one other metacentric. The overall geographical distribution of different Rb fusions seems to match an early stage of race formation. The eventual role of the presently studied hybrid zone in the context of chromosomal speciation by monobrachial centric fusions is discussed. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, , 722-731. [ABSTRACT FROM AUTHOR]

The costs of bird song incurred in a diversity of ways may result in trade-offs in the production and maintenance of elaborate plumage ornaments. In this paper, we examine evolutionary trade-offs between acoustic and visual signalling in trogon birds (Trogonidae). Using multiple regressions with phylogenetically independent contrasts, we found that interspecific variation in male plumage coloration was not significantly predicted by song traits (reduced by PCA) or altitude. Although plumage coloration is expected to decrease with increases in song elaboration, both groups of variables were not related. Given that song and plumage coloration traits are likely targets of sexual selection, we also examined their relationships with sexual plumage dimorphism. We found that male carotenoid-derived coloration was positively related to sexual plumage dimorphism, suggesting that sexual selection on male carotenoid-derived coloration may be stronger than on melanin- or structurally based coloration, or than on acoustic traits. Comparative studies on other bird families accounting for the effects of phylogeny as well as environmental covariates are required to test the generality of our findings in trogons. [ABSTRACT FROM AUTHOR]

The analysis of diversification and character evolution using phylogenetic data attracts increasing interest from biologists. Recent statistical developments have resulted in a variety of tools for the inference of macroevolutionary processes in a phylogenetic context. In a recent paper Maddison (2006 Evolution, 60: 1743–1746) pointed out that uncareful use of some of these tools could lead to misleading conclusions on diversification or character evolution, and thus to difficulties in distinguishing both phenomena. I here present guidelines for the analyses of macroevolutionary data that may help to avoid these problems. The proper use of recently developed statistical methods may help to untangle diversification and character change, and so will allow us to address important evolutionary questions. [ABSTRACT FROM AUTHOR]

Rates of phenotypic evolution have changed throughout the history of life, producing variation in levels of morphological, functional, and ecological diversity among groups. Testing for the presence of these rate shifts is a key component of evaluating hypotheses about what causes them. In this paper, general predictions regarding changes in phenotypic diversity as a function of evolutionary history and rates are developed, and tests are derived to evaluate rate changes. Simulations show that these tests are more powerful than existing tests using standardized contrasts. The new approaches are distributed in an application called Brownie and in r8s. [ABSTRACT FROM AUTHOR]

Vicariance and dispersal hypotheses have been proposed over the last two hundred years to explain the distribution, diversity, and faunal composition of the Caribbean biota. Despite great advances in understanding the geological history of the region, recent biogeographical reviews have not used historical biogeographical methods. In this paper I review the taxonomy, distribution and phylogeny of all Cenozoic Caribbean non-volant mammals and four bat lineages, and present reconciled trees for available phylogenies. Dates available from the fossil record and hypotheses of divergence based on molecular phylogenetic studies are also included in general assessments of fit between proposed geological models and Caribbean mammal diversification. The evidence posited in mammalian phylogenies does not add to the argument of dispersal vs. vicariance. One previously unidentified temporal pattern, the colonization of the Caribbean by South American mammals between the Palaeocene and the Middle Miocene, accounts for the distribution and phylogeny of the majority of lineages studied. Choloepodine and megalocnine sloths, hystricognath rodents, and primates all arrived during this window of colonization. Of these, megalocnine sloths, hystricognath rodents, Brachyphylla and allied bats, Stenodermatina bats, and primates fit the pattern of divergence from the mainland implied by the Gaarlandia hypothesis. Sloths, rodents and primates also roughly fit the timing of arrival to the Caribbean implied by Gaarlandia. The remaining taxa show contradictory dates of divergence according to molecular clock estimates, and no taxa fit the predicted timing and pattern of divergence among Antillean landmasses under the Gaarlandia model. Choloepodine sloths, murid rodents, insectivorans, mormoopids, and natalids show patterns of divergence from the mainland that are inconsistent with the Gaarlandia hypothesis and seem to require taxon-specific biogeographical explanations. © 2004 The Linnean Society of London, Biological Journal of the Linnean Society, 2004, 81, 373–394. [ABSTRACT FROM AUTHOR]