Possible atavisms of genitalia in two species of earwig (Dermaptera), Proreus simulans (Chelisochidae) and Euborellia plebeja (Anisolabididae)

Male and female genitalia generally show a rapid evolutionary rate, which raises the problems related to homologization and the determination of the polarities of evolutionary changes. In earwigs (Dermaptera), multiple or branched female sperm-storage organs (spermathecae) have been reported for members of the Karschiellidae, Pygidicranidae, and Diplatyidae, collectively termed the “basal” Dermaptera. Whether the complicated spermathecae represent a plesiomorphy or an apomorphy has not been resolved. Here I report the occurrence of multiple or branched spermathecae in gamma-irradiated samples of two earwig species, Euborellia plebeja (Dohrn, 1863) (Anisolabididae) and Proreus simulans (Stål, 1860) (Chelisochidae), which belong to the “higher” Dermaptera (Apachyidae, Labiduridae, Anisolabididae, Spongiphoridae, Chelisochidae, and Forficulidae). Females belonging to the higher Dermaptera normally have a single-unbranched spermatheca. I discuss examples of possible atavisms in relation to the evolutionary pathways of spermathecal morphology. Possible atavisms in the number of male organs for sperm transfer (virgae) are also reported.     

Embryos in evolution: evo-devo at the Naples Zoological Station in 1874

Eighteen seventy-four was a high point in evolutionary embryology. Thanks to Charles Darwin, the theory of evolution by natural selection provided a revolutionary new way of viewing the relationships and origins of organisms on Earth. Thanks to Ernst Haeckel, embryos were the way to study evolution (Haeckel in Generelle morphologie der organismen, vols 1, 2. Verlag Georg Reimer, Berlin, 1866)—it really was embryos in evolution—and recapitulation was in the air. Thanks to Anton Dohrn, a new research facility was on the ground, designed, located and structured to facilitate the study of embryos in evolution. Anton Dohrn devised, designed, financed, supervised the construction and then administered the Naples Zoological Station specifically so that researchers from all nations would have a facility where Darwin’s theory of evolution by natural selection could be tested. The zoologists who took advantage of the brand new facility within weeks of its opening late in 1873 established lines of research into evolutionary embryology, the field we now know as evolutionary developmental biology (evo-devo), the study of embryos in evolution. I examine the approach taken by Ambrosius Hubrecht, the first Dutch embryologist to undertake research at the station, and then evaluate the research of three British zoologists—E. Ray Lankester, Albert Dew-Smith, and Francis Maitland (Frank) Balfour. All four sought insights into origins, especially vertebrate origins that rested on comparative embryology, homology, germ layers, and a Darwinian approach to origins.

Evolution of wing polymorphism and genital asymmetry in the thread‐legged bugs of the tribe Metapterini Stål (Hemiptera,Reduviidae, Emesinae) based on morphological characters

Wing polymorphism and asymmetric male genitalia are intriguing morphological phenomena occurring in insects. Among Emesinae, or thread‐legged bugs, the tribe Metapterini Stål exhibits these two interesting morphological attributes. Nonetheless, evolutionary interpretations of these phenomena cannot be put forward because phylogenetic hypotheses for Emesinae are lacking. Thread‐legged bugs are easily recognized among assassin bugs due to their elongated and seemingly delicate body. The tribe Metapterini has 28 genera and approximately 280 described species. The only available phylogenetic hypothesis among Emesinae tribes was proposed by Wygodzinsky (1966), and it hypothesized Deliastini Villiers as the sister group of Metapterini, although this hypothesis has never been tested with cladistic approaches. Recent analyses using character sets of genitalia and prolegs suggest that Metapterini might not be monophyletic. In order to test these ideas, we compiled a morphological dataset of 138 characters that includes external morphological characters, detailed features of prolegs and genitalia of both sexes for Metapterini, which were analysed cladistically including 55 terminals, comprising 24 genera (85.7% of the generic diversity), 43 species of Metapterini and 12 outgroups. Metapterini was recovered as paraphyletic by the inclusion of Bergemesa Wygodzinsky, Palacus Dohrn and Stalemesa Wygodzinsky, all currently assigned to Deliastini. Gardena Dohrn (Emesini) was recovered as the sister group of Metapterini + Deliastini as suggested by Wygodzinsky (1966). Based on these results, we synonymize Deliastini syn. n. with Metapterini sensu n. and propose two new genera: Bacata Castro‐Huertas & Forero gen. n. , for three Andean species previously placed in Liaghinella Wygodzinsky, and Valkyriella Castro‐Huertas & Forero gen. n. for Ghilianella borgmeieri Wygodzinsky. Ancestral state reconstruction of wing polymorphism indicates that males and females were fully winged in the ancestor of Metapterini sensu n. with two independent evolutionary transitions to the apterous and brachypterous conditions. The analysis of the symmetry of the male genitalia shows an ancestor with symmetric male genitalia and two independent emergences of asymmetrical male genitalia in Metapterini.     

Book notices

Monograph of the genus Dieuches Dohrn (Heteroptera: Lygaeidae), by A.C.Eyles Rearing the Hymenoptera Parasitica, by K.G.V.Smith     

Über den feineren Bau der Rinde des Seeigeleies

Ohne ZusammenfassungDie Arbeit wurde in der Zoologischen Station in Neapel ausgeführt. Dem Direktor, Herrn Professor R. Dohrn sowie den übrigen Herren der Station danke ich für die wohlwollende Unterstützung meiner Unter-suchungen.     

Carl Gegenbaur versus Anton Dohrn

Summary Both Carl Gegenbaur and Ernst Haeckel feuded with Anton Dohrn with respect to vertebrate origins and how one should study phylogeny. Although they argued about methodology, and also had serious differences with respect to philosophical issues, their different personal agendas with respect to research and institution-building may have been equally significant.     

Autosomal polyploidy and male meiotic pattern in the bug family Nabidae (Heteroptera)

Karyotypes of 18 species of Nabidae (Heteroptera), belonging to the genera Nabis (11), Himacerus (3), Hoplistoscelis (1), and Pagasa (1) were studied. The data on Nabis meridionalis Kerzhner 1963, N. tesquorum (Kerzhner 1968), N. ussuriensis (Kerzhner 1962), N. pallidus Fieber 1861, N. sareptanus Dohrn 1862, Hoplistoscelis sordidus (Reuter 1872), and Pagasa fusca (Stein 1857) were obtained for the first time in this study. Karyotypes of Nabis punctatus A. Costa 1847, N. ferus (Linnaeus 1758), N. pseudoferus Remane 1949, N. rugosus (Linnaeus 1758), N. stenoferus Hsiao 1964, N. limbatus Dahlbom 1851, N. reuteri Jakovlev 1876, N. flavomarginatus Scholtz 1847, Himacerus apterus (Fabricius 1798), H. mirmicoides (O. Costa 1834), and H. maracandicus (Reuter 1890) were re-examined. A karyotype of 2n = 18 (16 + XY), which seems to be the most characteristic of Nabidae as a whole, was found in 12 species. Nabis pallidus and N. sareptanus showed a precise numerical doubling of the autosomal complement compared with the modal karyotype, 2n = 34 (32 + XY). Autosomal polyploidy is discussed as a possible evolutionary mechanism for these species. Meiosis in males of the above species was studied in detail. Male meiosis in Nabidae was shown to follow a highly peculiar scenario differing in many aspects from that known in the majority of the Heteroptera taxa.     

Developing the genotype-to-phenotype relationship in evolutionary theory: A primer of developmental features

For decades, there have been repeated calls for more integration across evolutionary and developmental biology. However, critiques in the literature and recent funding initiatives suggest this integration remains incomplete. We suggest one way forward is to consider how we elaborate the most basic concept of development, the relationship between genotype and phenotype, in traditional models of evolutionary processes. For some questions, when more complex features of development are accounted for, predictions of evolutionary processes shift. We present a primer on concepts of development to clarify confusion in the literature and fuel new questions and approaches. The basic features of development involve expanding a base model of genotype-to-phenotype to include the genome, space, and time. A layer of complexity is added by incorporating developmental systems, including signal-response systems and networks of interactions. The developmental emergence of function, which captures developmental feedbacks and phenotypic performance, offers further model elaborations that explicitly link fitness with developmental systems. Finally, developmental features such as plasticity and developmental niche construction conceptualize the link between a developing phenotype and the external environment, allowing for a fuller inclusion of ecology in evolutionary models. Incorporating aspects of developmental complexity into evolutionary models also accommodates a more pluralistic focus on the causal importance of developmental systems, individual organisms, or agents in generating evolutionary patterns. Thus, by laying out existing concepts of development, and considering how they are used across different fields, we can gain clarity in existing debates around the extended evolutionary synthesis and pursue new directions in evolutionary developmental biology. Finally, we consider how nesting developmental features in traditional models of evolution can highlight areas of evolutionary biology that need more theoretical attention.     

PRELIMINARY RESULTS ON SECONDARY METABOLITES FROM ANTARCTIC BROWN ALGAE AND THEIR ECOLOGICAL RELEVANCE

Ianora, A. Stazione Zoologica A. Dohrn, Villa Comunale 80121 Naples, Italy Traditionally, diatoms have been regarded as providing the bulk of the food that sustains the marine food chain to top consumers and important fisheries. However, this view has recently been challenged on the basis of laboratory studies showing that these small, unicellular algae possess anti-mitotic properties similar to the cytotoxic compounds isolated from numerous marine and terrestrial higher plants. In fact, when copepods, the principal predators of diatoms, are fed diatom diets, they produce abnormal eggs that either fail to develop to hatching or hatch into malformed nauplii that die soon afterwards. The aldehydes responsible for this anti-cell growth activity have recently been isolated and these compounds have been shown to arrest not only the development of copepod and sea urchin embryos, but also the proliferation of human carcinoma cells. In terrestrial environments, there are many reports of secondary metabolites produced by plants that interfere with the reproductive capacity of grazing animals, and which act as a form of population control. But this type of biological model is new for the marine environment where most of the attention on plant-animal interactions has focused on feeding deterrents and poisoning compounds. Such “birth-control” compounds may discourage herbivory by sabotaging future generations of grazers, thereby allowing diatom blooms to persist when grazing pressure would normally have caused them to crash.     

Discussion: Three Ways to Misunderstand Developmental Systems Theory

Developmental systems theory (DST) is a general theoretical perspective on development, heredity and evolution. It is intended to facilitate the study of interactions between the many factors that influence development without reviving `dichotomous' debates over nature or nurture, gene or environment, biology or culture. Several recent papers have addressed the relationship between DST and the thriving new discipline of evolutionary developmental biology (EDB). The contributions to this literature by evolutionary developmental biologists contain three important misunderstandings of DST.     

Resolving the Anti-Antievolutionism Dilemma: A Brief for Relational Evolutionary Thinking in Anthropology

ABSTRACT   Anthropologists often disagree about whether, or in what ways, anthropology is "evolutionary." Anthropologists defending accounts of primate or human biological development and evolution that conflict with mainstream "neo-Darwinian" thinking have sometimes been called "creationists" or have been accused of being "antiscience." As a result, many cultural anthropologists struggle with an "anti-antievolutionism" dilemma: they are more comfortable opposing the critics of evolutionary biology, broadly conceived, than they are defending mainstream evolutionary views with which they disagree. Evolutionary theory, however, comes in many forms. Relational evolutionary approaches such as Developmental Systems Theory, niche construction, and autopoiesis–natural drift augment mainstream evolutionary thinking in ways that should prove attractive to many anthropologists who wish to affirm evolution but are dissatisfied with current "neo-Darwinian" hegemony. Relational evolutionary thinking moves evolutionary discussion away from reductionism and sterile nature–nurture debates and promises to enable fresh approaches to a range of problems across the subfields of anthropology. [Keywords: evolutionary anthropology, Developmental Systems Theory, niche construction, autopoeisis, natural drift]     

First report on C-banding and fluorescent banding in species of Dieuches (Rhyparochrominae: Lygaeidae: Heteroptera)

Although the karyotypes of twelve species of Dieuches Dohrn, 1860 belonging to Rhyparochrominae have been described so far, there is no information about heterochromatin and its characterization in terms of base composition for any of the species. In the present paper, C-banding and fluorescent banding have been applied for the first time to three species of Dieuches : D. uniguttatus, D. insignis (2n = 12 = 8A + 2m + XY) and D. coloratus (2n = 14 = 10A + 2m + XY). Dieuches uniguttatus and D. insignis show distinct terminal C-bands along with a few interstitial bands in all the autosomal bivalents, whereas in D. coloratus , one autosomal pair is almost completely heterochromatic, three show C-positive bands while one is totally euchromatic. The sex chromosomes too show heterogeneity in distribution of C-heterochromatin among three Dieuches species. Characterization of heterochromatin in D. uniguttatus and D. insignis using DAPI/CMA₃ staining reveals that in D. uniguttatus , C- heterochromatin blocks of all the autosomal bivalents, which are predominantly A–T rich, whereas in D. insignis , these are rich both in A–T and G–C. In D. uniguttatus, sex chromosomes X and Y have localized G–C rich regions whereas in D. insignis , these are scattered in X and absent in Y. As variations in the heterochromatin represent the main source of karyological differentiation among and within species, it seems that there occurred extensive redistribution of heterochromatin within the complement as the three species evolved. There is need for cytological details of more species to understand evolutionary aspects in the genus Dieuches .     

Evolutionary developmental biology its roots and characteristics

The rise of evolutionary developmental biology was not the progressive isolation and characterization of developmental genes and gene networks. Many obstacles had to be overcome: the idea that all genes were more or less involved in development; the evidence that developmental processes in insects had nothing in common with those of vertebrates.Different lines of research converged toward the creation of evolutionary developmental biology, giving this field of research its present heterogeneity. This does not prevent all those working in the field from sharing the conviction that a precise characterization of evolutionary variations is required to fully understand the evolutionary process.Some evolutionary developmental biologists directly challenge the Modern Synthesis. I propose some ways to reconcile these apparently opposed visions of evolution. The turbulence seen in evolutionary developmental biology reflects the present entry of history into biology.     

The evolution of phenotypic polymorphism: randomized strategies versus evolutionary branching

A population is polymorphic when its members fall into two or more categories, referred to as alternative phenotypes. There are many kinds of phenotypic polymorphisms, with specialization in reproduction, feeding, dispersal, or protection from predators. An individual's phenotype might be randomly assigned during development, genetically determined, or set by environmental cues. These three possibilities correspond to a mixed strategy of development, a genetic polymorphism, and a conditional strategy. Using the perspective of adaptive dynamics, I develop a unifying evolutionary theory of systems of determination of alternative phenotypes, focusing on the relative possibilities for random versus genetic determination. The approach is an extension of the analysis of evolutionary branching in adaptive dynamics. It compares the possibility that there will be evolutionary branching, leading to genetic polymorphism, with the possibility that a mixed strategy evolves. The comparison is based on the strength of selection for the different outcomes. An interpretation of the resulting criterion is that genetic polymorphism is favored over random determination of the phenotype if an individual's heritable genotype is an adaptively advantageous cue for development. I argue that it can be helpful to regard genetic polymorphism as a special case of phenotypic plasticity.     

Phylogeny and evo-devo: characters, homology, and the historical analysis of the evolution of development

The concept of homology continues to attract more and more commentary. In systematic and evolutionary biology the meaning of homology as synapomorphic similarity inherited from a common ancestor has gained wide acceptance over the last three or four decades. In recent years, however, developmental biologists, in particular, have argued for a new approach to, and new definition for, homology that revolves around the desire to make it more process-oriented and more mechanistic. These efforts raise questions about the relationship between developmental and evolutionary biology as well as how the evolution of development is to be studied. It is argued in this paper that this new approach to homology seemingly decouples developmental biology from the study of the evolution of development rather than to facilitate that study. In contrast, applying the notion of historical, phylogenetic homology to developmental data is inherently comparative and therefore evolutionary.     

以发育模块重复征用和整合为基础的进化创新机制

进化新征的起源和分化是进化发育生物学研究的核心问题。通过对多细胞生物早期发育调控机制的比较分析,发现亲缘关系较远的生物所共有的一些形态特征受保守的发育调控程序调节（深同源性）。许多创新性状的发生是基于对预先存在的基因或发育调控模块的重复利用和整合。发育基因调控网络在结构和功能上高度模块化,因此不仅可以通过模块拆分和重复征用改变发育程式,而且也增强了调控网络自身的进化力。研究基因调控网络和发育系统的进化动态将有助于更深入地认识生物演化过程中创新性状发生和表型进化的分子机制。     

How to Explore Morphological Integration in Human Evolution and Development?

Most studies in evolutionary developmental biology focus on large-scale evolutionary processes using experimental or molecular approaches, whereas evolutionary quantitative genetics provides mathematical models of the influence of heritable phenotypic variation on the short-term response to natural selection. Studies of morphological integration typically are situated in-between these two styles of explanation. They are based on the consilience of observed phenotypic covariances with qualitative developmental, functional, or evolutionary models. Here we review different forms of integration along with multiple other sources of phenotypic covariances, such as geometric and spatial dependencies among measurements. We discuss one multivariate method [partial least squares analysis (PLS)] to model phenotypic covariances and demonstrate how it can be applied to study developmental integration using two empirical examples. In the first example we use PLS to study integration between the cranial base and the face in human postnatal development. Because the data are longitudinal, we can model both cross-sectional integration and integration of growth itself, i.e., how cross-sectional variance and covariance is actually generated in the course of ontogeny. We find one factor of developmental integration (connecting facial size and the length of the anterior cranial base) that is highly canalized during postnatal development, leading to decreasing cross-sectional variance and covariance. A second factor (overall cranial length to height ratio) is less canalized and leads to increasing (co)variance. In a second example, we examine the evolutionary significance of these patterns by comparing cranial integration in humans to that in chimpanzees.     

Evolution and development of scyphozoan jellyfish

Scyphozoan jellyfish, or scyphomedusae, are conspicuous members of many ocean ecosystems, and have large impacts on human health and industry. Most scyphomedusae are the final stage in a complex life cycle that also includes two intermediate stages: the larval planula and benthic polyp. In species with all three life‐cycle stages, the metamorphosis of a polyp into a juvenile scyphomedusa (ephyra) is termed strobilation, and polyps can produce one ephyra (termed monodisc strobilation) or many ephyrae (termed polydisc strobilation). In contrast to species with planula, polyp and medusa stages, a handful of scyphozoan species possess modified life cycles with reduced or absent stages. The evolutionary patterns associated with strobilation and life‐cycle type have not been thoroughly investigated, and many studies of ephyra development and strobilation induction are not yet synthesized. Herein, I place the development of scyphomedusae in an evolutionary context. I first review the current evolutionary hypotheses for Scyphozoa. Next, I review what is known about scyphomedusa development across a broad diversity of species, including the first signs of strobilation, the formation of strobila segments, and the morphogenesis of ephyrae. I then review cases where the canonical scyphozoan life cycle has been modified, and take advantage of phylogenetic hypotheses to place these observations in an evolutionary context. I show that the evolution of monodisc strobilation occurred at least twice, and that the loss of intermediate life‐cycle stages occurred several times independently; by contrast, the reduction of the medusa stage appears to have occurred within a single clade. I then briefly review the major natural cues of strobilation induction. Finally, I summarize what is currently known about the molecular mechanisms of strobilation induction and ephyra development. I conclude with suggestions for future directions in the field.