Patterns of praying mantis auditory system evolution based on morphological, molecular, neurophysiological, and behavioural data

Some praying mantids have sensitive ultrasonic hearing arising from a unique 'cyclopean' ear located in the ventral metathorax. The present study explores the evolutionary history of the mantis auditory system by integrating large anatomical, neurophysiological, behavioural, and molecular databases. Using an 'auditory phylogeny' based on 13 morphological characters, we identified a primitively earless form of metathoracic anatomy in several extant taxa. In addition, there are five distinct mantis auditory systems. Three of these can be identified anatomically, and the other two can only be detected neurophysiologically. Superimposing these results onto a phylogenetic tree derived from molecular data from seven genes shows that the cyclopean mantis ear evolved once approximately 120 Mya. All the other auditory system types are either varying degrees of secondary loss, or are recent innovations that each occurred independently multiple times. The neurophysiological response to ultrasound is remarkably consistent across all taxa tested, as is the multicomponent, in-flight behaviour triggered by ultrasound. Thus, mantids have an ancient, highly conserved auditory neural–behavioural system. Although ultrasonic hearing in several insect groups evolved in response to bat predation, mantis hearing predates the appearance of bats (approximately 63 Mya) and must originally have functioned in communication, prey detection, or avoidance of nonbat predators.  © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 94 , 541–568.     

Phylogeny of the Afro-Madagascan Aristea (Iridaceae) revisited in the light of new data on pollen morphology

Scanning and electron microscopic studies of the pollen grains of several species of the sub-Saharan African and Madagascan genus Aristea of c . 50 species, supplement data from an earlier study and enable us to include these species in a phylogenetic analysis. TEM examination of a range of pollen grains of representative pollen types in Aristea makes it possible to reinterpret past SEM results so that apertures covered with exine masses and previously called sulculate, are now seen to be either zonasulculate or dizonasulculate. Revised and expanded data are combined in a matrix together with new data for seed morphology in the genus, which like the capsules is remarkably diverse, including angular seeds with reticulate sculpturing, lamellate or triangular-columnar seeds with smooth or reticulate surfaces and with smooth or papillate or areolate margins. This new phylogenetic analysis suggests that Aristea should remain treated as comprising three subgenera. In subgenus Eucapsulares we add a new section Latifolieae for A. latifolia , which seems an isolated relic restricted to the mountains of the Cape Region of South Africa, an area of winter rainfall. Species with similar unspecialized capsule and seed morphology occur only in eastern south and tropical Africa and Madagascar, but they have derived pollen morphology whereas the pollen of A. latifolia is plesiomorphic. This species appears to be the closest living ancestor of the genus. In subgenus Aristea we continue to recognize three sections, sect. Racemosae , sect. Singulares and sect. Aristea. Nesting of subgenus Pseudaristea within section Racemosae of subgenus Aristea is probably an artefact of the analysis and does not receive bootstrap support, and hence we continue to recognize this group of species at subgeneric rank.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 144 , 41–68.     

Patterns of morphological evolution in Marmota (Rodentia, Sciuridae): geometric morphometrics of the cranium in the context of marmot phylogeny, ecology and conservation

Marmots are of great interest for both sociobiologists studying the evolution of mammal societies and conservationists trying to protect them from extinction. In contrast, their phylogeny and morphological evolution are poorly understood and studied. Recently, a phylogenetic analysis using cytochrome b provided the first reconstruction of marmot evolutionary history and suggested that a high level of sociality evolved at least twice independently in the two proposed marmot subgenera. A morphological analysis of the marmot mandible supported this subgeneric classification and showed interesting, and unexpected, patterns in the evolution of marmot skeletal characters. In the present study we investigated a more complex, and potentially informative structure, the ventral cranium. Geometric morphometric techniques were applied in the first analysis of cranial morphology including all marmot species. Three main phenetic groups were found, which reflect phylogeny (subgenus Petromarmota , and Palaearctic subgenus Marmota ) or geographical distribution (Palaearctic vs. Nearctic subgenus Marmota ). Convergence in skeletal characters due to size similarities, a common finding in the sciurid skeleton according to traditional morphological analyses, did not occur in the marmot ventral cranium. Despite a genetic distance between Marmota vancouverensis and Marmota caligata similar to that among different populations of the latter species, the Vancouver Island marmot had the most atypical ventral cranium in the subgenus Petromarmota . This finding confirmed results obtained with the mandible, and emphasized the uniqueness of M. vancouverensis and the usefulness of complementing molecular analyses with morphological studies for a thorough characterization of population divergence, and a careful planning of conservation strategies.  © 2004 The Linnean Society of London, Biological Journal of the Linnean Society , 2004, 82 , 385–407     

Distribution and genetic divergence of two parapatric sibling ant species in Central Europe

The two sibling ant species Temnothorax nylanderi and Temnothorax crassispinus are widely distributed throughout deciduous forests in Europe. Their resemblance in morphology and similar ecological requirements suggest that they evolved from the same ancestral species in different glacial refugia and re-immigrated into Central Europe after the last ice age. Here, we show that the two species are parapatrically distributed in south-eastern Germany and hybridize along a narrow contact zone close to the continental divide. Phylogeographical data based on the mitochondrial genes cytochrome oxidase subunit I and cytochrome b suggest that the dominant haplotypes for T. nylanderi and T. crassispinus might have diverged already 1.5–2 Mya. Intraspecific variability is extremely low in both species, which might be explained by severe bottlenecks during rapid postglacial expansion into Central Europe.  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 88 , 223–234.     

Mitochondrial differentiation, introgression and phylogeny of species in the Tegenaria atrica group (Araneae: Agelenidae)

The relationships between the three members of the Tegenaria atrica group ( T. atrica , T. saeva and T. gigantea ) were examined with DNA sequence data from mitochondrial CO1, 16S rRNA, tRNA^leu(CUN) and ND1 genes. Members of this group of large house spiders have overlapping distributions in western Europe and hybridize with each other to a variable degree. The close relatedness of all three species was supported by all analyses. T. saeva and T. gigantea are more closely affiliated than either is to T. atrica . Haplotypes clearly assignable to T. gigantea were also present in many specimens of T. saeva , suggesting asymmetrical introgression of mtDNA from T. gigantea into T. saeva . Molecular clock calibrations (CO1) suggest that deeper divisions within the genus Tegenaria may be in excess of 10 million years old, and that the evolutionary history of the T. atrica group has been moulded by Quaternary glacial–interglacial cycles.  © 2004 The Linnean Society of London, Biological Journal of the Linnean Society , 2004, 81 , 79–89.     

Evolution of St Helena arborescent Astereae (Asteraceae): relationships of the genera Commidendrum and Melanodendron

The cladistic relationships of endemic Commidendrum (four species) and Melanodendron (one species) from St Helena were inferred from sequences of ITS1 and ITS2 of nuclear ribosomal DNA. Despite showing a range of morphological and ecological variation, the four species of Commidendrum , C. spurium , C. robustum , C. rotundifolium , and C. rugosum , form a closely related monophyletic group with percentage sequence divergence between 0.2 and 0.9%. Melanodendron integrifolium is sister to Commidendrum indicating that the two genera may have evolved from a common ancestor that arrived in St Helena via a single dispersal event. The closest relatives of Commidendrum and Melanodendron appear to be South African, in the predominantly shrubby genus Felicia , although further sampling of South African Astereae is required. We discuss the evolution and adaptive radiation of these rare and threatened species with particular reference to the possible role of heterochrony.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 144 , 69–83.     

A new divergent lineage of Daphnia (Cladocera: Anomopoda) and its morphological and genetical differentiation from Daphnia curvirostris Eylmann, 1887

The systematic biology of the subgenus Daphnia s . s . remains confused. Prior attempts at resolution used chiefly postabdominal claw morphology, chromosome numbers and rRNA gene sequences as characters for higher-level relations. Still, several taxa, such as Daphnia curvirostris Eylmann, 1878, have unclear affiliations. We addressed the position of D. curvirostris in this genus by estimating phylogenetic trees from a rapidly evolving protein coding gene (ND2), conducting broad geographical comparisons and carrying out detailed morphological comparisons. The Japanese ' curvirostris' was found to be a new divergent lineage in the subgenus Daphnia , and to possess distinctive morphological characteristics from D. curvirostris . We described this new species as Daphnia tanakai sp. nov. , and redescribed D. curvirostris . The polymorphic postabdominal claw morphology and the distinctive chromosome number of D. tanakai sp. nov. provided evidence for rapid evolution of these traits. Our new morphological, chromosomal and genetic assessment of Daphnia weakened the argument for division of the subgenus Daphnia ( Daphnia ) O. F. Müller, 1785 sensu Johnson, 1952, into two further subgenera.  © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society , 2006, 146 , 385–405.     

Karyomorphology of Incarvillea (Bignoniaceae) and its implications in distribution and taxonomy

The karyomorphology of 11 species of the genus Incarvillea Juss. is reported. The chromosome numbers of all species studied are 2 n  = 22. The interphase nuclei and prophase chromosomes were found to be of the simple chromocentre type and the interstitial type, respectively. The asymmetry of the karyotype of I. arguta (two populations) in subgenus Amphicome is type 2A. The karyotypes of Incarvillea s inensis var. sinensis , I.  s inensis var. przewalskii, and I. olgae in subgenus Incarvillea are of asymmetry type 3A. The remaining nine species and one variety in subgenus Pteroscleris are also of asymmetry 3A. Data on three species and one variety studied are first reports. This study indicates that karyotype variation at the diploid level appears to be the predominant feature of chromosome evolution in the genus Incarvillea . According to this study of karyomorphology, morphological characteristics and geographical distribution, it seems that the three subgenera should be regarded as three independent genera. The geography of the genus is discussed.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 144 , 113–121.     

A new species of Typhlatya (Crustacea: Decapoda: Atyidae) from anchialine caves on the French Mediterranean coast

A new species of the thermophylic Tethyan relict prawn Typhlatya is described from two anchialine caves near Perpignan (southern France). The new species is closely related to a congener known only from a freshwater cave at Castellón (eastern Spain), about 400 km to the south-west, differing apparently only in the size and shape of the rostrum and the armature of the dactylus of the fifth pereiopod. Based on palaeogeographical evidence and assuming a sister-group relationship between both species, we suggest that their common ancestor could not be older than early Pliocene in age, and that it was already a stygobiont taxon adapted to live in shallow-water marine crevicular habitats. This ancestor would have vanished from the western Mediterranean after the cooling associated with the onset of northern Hemisphere glaciation, about 3 Mya, as documented for other Mediterranean marine taxa. Indeed, the genus is completely stygobiont and does not occur in fluvial environments. The Pyrenees represent a watershed boundary that eliminates the possibility of the derivation of one species from the other by active dispersal after establishment in continental waters.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 144 , 387–414.     

The evolutionary pathway of light emission in myodocopid Ostracoda

The evolutionary history of bioluminescence and iridescence in myodocopid ostracods was estimated by phylogenetic analysis of mitochondrial 16S ribosomal RNA sequences. The inferred phylogeny of the myodocopids suggests that the common ancestor of Myodocopida evaluated in this study exhibits iridescence. This type of light emission was once lost and recaptured independently in the descendant lineages. Bioluminescent species also evolved from non-luminous ancestral species. In the suborder Myodocopina, all the bioluminescent species form a monophyletic group, suggesting that bioluminescence evolved only once. Structural differences between two bioluminescent groups in the order Myodocopida suggests independent origins for bioluminescence.  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 87 , 449–455.     

Convergent evolution of the cavefish Astyanax (Characidae, Teleostei): genetic evidence from reduced eye-size and pigmentation

More than 20 populations of the cave-dwelling characid Astyanax occur within a restricted karst area in Mexico. The fish possess reduced eyes without lenses and visual cells. It is still an open question as to whether this condition evolved convergently after multiple entries of the surface ancestor into the different caves or whether a single cave ancestor, already characterized by reduced eyes, spread secondarily within them. In the crosses between specific populations, specimens appear that deviate considerably from those of the parents. They possess larger and better-developed eyes with histologically intact lenses and visual cells; they thus have the structural potential for vision. This indicates that in different cave populations, different mutations in the eye gene system have occurred. In cases where these non-functional rudimentary genes are recombined in hybrid specimens, gene expression may be restored. This is the result of separate evolution of several Astyanax cave populations.  © 2003 The Linnean Society of London, Biological Journal of the Linnean Society, 2003, 80 , 545−554.     

Plio-Pleistocene Carnivora of eastern Africa: species richness and turnover patterns

This paper presents an up-to-date and detailed overview of the Plio-Pleistocene fossil record of Carnivora in eastern Africa. Major events in the carnivoran lineages present in the region are discussed and stratigraphic ranges of all species-level taxa are provided. The compiled data are used for quantitative analyses of species richness and turnover. Sampling is considered to be adequate for the interval 3.6–1.5 Mya, and poorer in the half-million-year time slices before and after this interval. Species richness peaks around 3.6–3.0 Mya and declines gradually from that time until the end of the time period analysed. Calculation of origination and extinction rates indicate that there are two peaks of origination: at 3.9–3.3 Mya (although the earlier half of this interval is biased through poor sampling) and at 2.1–1.8 Mya. The origination rate is zero in the interval 3.0–2.4 Mya. The extinction rate peaks at around 3.0 Mya after which it falls slightly, remaining nearly constant until 1.8 Mya, after which it increases considerably. The data support the hypothesis that the modern carnivoran guild of eastern Africa originated relatively recently, mostly within the last million years. There is no support in these data for a turnover pulse in Carnivora between 3 and 2 Mya.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 144 , 121–144.     

Nomenclature in the dock. Overclassification leads to instability: a case study in the horticulturally important genus Cyclamen (Myrsinaceae)

Nine different classifications have been produced in the last 70 years for the horticulturally valuable genus Cyclamen , a small genus with fewer than 30 species. These classifications, generated by intuitive methods and cladistic analyses, incorporated a total of four infrageneric ranks above that of species and were based on data from morphology, cytology and DNA sequencing. Our results, based on cladistic analyses of three independent data sources − nrDNA ITS, cpDNA trn L intron and morphological data − reveal good resolution only in nrDNA sequence data. However, when these three data sources are combined they provide stronger resolution and support for three major clades, only one of which, subgenus Psilanthum , has been consistently supported in previous classifications. The differing infrageneric classifications produced in Cyclamen result from varying taxon sampling, differing interpretation of morphological data, changes in the sources and analysis of data, and inconsistent application of names. Extensive subdivision of small genera in the absence of adequate data that could provide evidence for consistent patterns of relationship is premature and leads to a proliferation of names.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 339–349.     

Evolution of the perennial soybean polyploid complex (Glycine subgenus Glycine): a study of contrasts

Glycine subgenus Glycine , the sister group to the cultivated soybean and its progenitor, have received considerable study over several decades. The combination of biosystematic data and an extensive germplasm collection has provided a strong foundation for molecular systematic studies in the group, including those on allopolyploids. These studies have shown that the various polyploid taxa known from the subgenus are all part of a single large allopolyploid complex, linked by shared diploid genomes. Many elements of the complex have arisen recently, and most show evidence of recurrent origins. However, there are also many dissimilarities among even closely related polyploids. Polyploids differ from one another in such ways as number of origins, amount of allelic diversity harboured at different loci, bidirectional vs. unidirectional origins, retention of ribosomal gene homoeologues, success as measured by geographical range and abundance, and patterns of gene expression.  © 2004 The Linnean Society of London, Biological Journal of the Linnean Society , 2004, 82 , 583–597.     

Fritillary phylogeny, classification, and larval host plants: reconstructed mainly on the basis of male and female genitalic morphology (Lepidoptera: Nymphalidae: Argynnini)

Species-level phylogeny of the Butterfly tribe Argynnini is established based on 141 characters derived from wing and genitalia morphology of both sexes. The Argynnini can be divided into three subtribes; Yrameina comprising Yramea and Boloria s . l ., Argynnina comprising Prokuekenthaliella , Issoria , Brenthis , and all the 'large fritillary' species joined in the genus Argynnis s . l . and a new subtribe Euptoietina comprising only the genus Euptoieta . The classical genus Issoria s . l . is polyphyletic regarding Yramea and possibly paraphyletic regarding the two Afrotropic species baumanni and hanningtoni ; these two species are tentatively transferred to the old genus/subgenus Prokuekenthaliella . Surprisingly, one Afrotropic species, Issoria smaragdifera is closely related to the East Palaearctic Issoria species. A revised classification of Argynnini is proposed based on the obtained phylogeny. Studies of larval host plants based on the obtained phylogeny suggest that the ancestral Argynnini used Passiflora and Violaceae, but already the ancestor of Yrameina + Argynnina was probably specialized on Violaceae. Whereas the Boloria species have turned to other food plants such as Dryas , Vaccinium and Salix on several occasions, only Brenthis among the Argynnina use other host plants than Viola (mainly Rosaceae). The habit of laying eggs away from the food plant has probably evolved twice within Argynnina.  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 89 , 627–673.     

Loss of egg yolk genes in mammals and the origin of lactation and placentation

Embryonic development in nonmammalian vertebrates depends entirely on nutritional reserves that are predominantly derived from vitellogenin proteins and stored in egg yolk. Mammals have evolved new resources, such as lactation and placentation, to nourish their developing and early offspring. However, the evolutionary timing and molecular events associated with this major phenotypic transition are not known. By means of sensitive comparative genomics analyses and evolutionary simulations, we here show that the three ancestral vitellogenin-encoding genes were progressively lost during mammalian evolution (until around 30–70 million years ago, Mya) in all but the egg-laying monotremes, which have retained a functional vitellogenin gene. Our analyses also provide evidence that the major milk resource genes, caseins, which have similar functional properties as vitellogenins, appeared in the common mammalian ancestor ∼200–310 Mya. Together, our data are compatible with the hypothesis that the emergence of lactation in the common mammalian ancestor and the development of placentation in eutherian and marsupial mammals allowed for the gradual loss of yolk-dependent nourishment during mammalian evolution.     

Morphological evidence for sister group relationship between flamingos (Aves: Phoenicopteridae) and grebes (Podicipedidae)

A recent molecular analysis strongly supported sister group relationship between flamingos (Phoenicopteridae) and grebes (Podicipedidae), a hypothesis which has not been suggested before. Flamingos are long-legged filter-feeders whereas grebes are morphologically quite divergent foot-propelled diving birds, and sister group relationship between these two taxa would thus provide an interesting example of evolution of different feeding strategies in birds. To test monophyly of a clade including grebes and flamingos, I performed a cladistic analysis of 70 morphological characters which were scored for 17 taxa. Parsimony analysis of these data supported monophyly of the taxon (Podicipedidae + Phoenicopteridae) and the clade received high bootstrap support. Previously overlooked morphological, oological and parasitological evidence is recorded which supports this hypothesis, and which makes the taxon (Podicipedidae + Phoenicopteridae) one of the best supported higher-level clades within modern birds. The phylogenetic significance of some fossil flamingo-like birds is discussed. The Middle Eocene taxon Juncitarsus is most likely the sister taxon of the clade (Podicipedidae + (Palaelodidae + Phoenicopteridae)) although resolution of its exact systematic position awaits revision of the fossil material. Contrary to previous assumptions, it is more parsimonious to assume that flamingos evolved from a highly aquatic ancestor than from a shorebird-like ancestor.  © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 140 , 157–169.     

Phylogenetics, zoogeography, and the role of dispersal and vicariance in the evolution of the Rana catesbeiana (Anura: Ranidae) species group

The Rana catesbeiana species group consists of seven species, each variously distributed across eastern North America. We estimated the evolutionary relationships among 31 exemplars and used the phylogenetic hypothesis to examine the potential modes of speciation and relative role of dispersal in the evolution and zoogeography of this species group. Phylogenetic relationships based on 1554 combined base pairs of the cytochrome b and ND2 mitochondrial genes suggest that the species are closely related, having undergone rapid radiation from a common ancestor during the late Miocene or Pliocene. A Pleistocene origin for the rare R. okaloosae is suggested by its pattern of paraphyly with R. clamitans and by its geographically restricted distribution, although hybridization as the explanation for paraphyly cannot be ruled out. Dispersal–vicariance analysis suggested a Coastal Plain biogeographical region origin of the species group, supporting the notion that the region was an important centre of anuran diversification, with post-speciation dispersal playing a major role in explaining the distribution of the widespread species, R. catesbeiana , R. clamitans, and R. septentrionalis . High sea levels during the late Tertiary, greatly reducing and insularizing parts of the southern Coastal Plain region may have played a major role in the diversification of this group.  © 2003 The Linnean Society of London, Biological Journal of the Linnean Society , 2003, 80 , 601–624.     

First record of fossil Mesozoic Ctenopoda (Crustacea, Cladocera)

Pre-Pleistocene representatives of the crustacean order Ctenopoda Sars, 1865 are unknown. Here we describe Mesozoic fossil specimens of ctenopods from two localities in Mongolia: Khotont (Jurassic/Cretaceous boundary, about 145 Mya) and Khutel Khara (Lower Cretaceous, about 129 Mya). All specimens apparently belonged to the tribe Latonini Korovchinsky, 1986 of the subfamily Sidinae Baird, 1850. At the Khotont site, ctenopods were the most numerous microscopic animal fossils. We assigned these cladocerans to a new genus and species Archelatona zherikhini gen. nov., sp. nov. Our findings support a pre-Cretaceous origin for cladocerans.  © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society , 2006, 146 , 269–274.