Cockroach homologs of praying mantis peripheral auditory system components

This study identifies the cuticular metathoracic structures in earless cockroaches that are the homologs to the peripheral auditory components in their sister taxon, praying mantids, and defines the nature of the cuticular transition from earless to eared in the Dictyoptera. The single, midline ear of mantids comprises an auditory chamber with complex walls that contain the tympana and chordotonal transduction elements. The corresponding area in cockroaches, between the furcasternum and coxae, has many socketed hairs arranged in discrete fields and the Nerve 7 chordotonal organ, the homolog of the mantis tympanal organ. The Nerve 7 chordotonal organ attaches at the apex of the lateral ventropleurite (LVp), which has the same shape and general structure as an auditory chamber wall. High-speed video shows that when the coxa moves toward the midline, the LVp rotates medially to stimulate socketed hairs, and also moves like a triangular hinge giving the chordotonal organ maximal in-out stimulation. Formation of the mantis auditory chamber from the LVp and adjacent structures would involve only enlargement, a shift toward the midline, and a mild rotation. Almost all proprioceptive function would be lost, which may constitute the major cost of building and maintaining the mantis ear. Isolation from leg movement dictates the position of the mantis ear in the midline and the rigid frame, formed by the cuticular knobs, which protects the chordotonal organs.     

A molecular study of phylogenetic relationships and evolution of antipredator strategies in Australian Diplodactylus geckos, subgenus Strophurus

We present phylogenetic analyses of the lizard genus Diplodactylus subgenus Strophurus using 1646 aligned positions of mitochondrial DNA sequences containing 893 parsimony-informative characters for samples of 12 species of Strophurus and 19 additional Australian gecko species. Sequences from three protein-coding genes (ND1, ND2 and COI) and eight intervening transfer RNA genes were examined using parsimony, maximum-likelihood and Bayesian analyses. Species of Strophurus appeared to form a monophyletic group with the possible exception of S. taenicauda . Strophurus has evolved two distinct defence/display characteristics: caudal glands, which expel an unpalatable substance, and striking mouth colours. Caudal glands appeared to have arisen once in a common ancestor of Strophurus , with dermal augmentation of caudal glands characterizing a subclade within the subgenus. Evolution of yellow and dark-blue mouth colours in Strophurus occurred in the context of diurnal activity and may be interpreted as an augmentation of defensive behavioural displays. Molecular divergence suggests that arboreality evolved in a common ancestor of Oedura and Strophurus approximately 29 Mya and that the caudal glands of Strophurus arose approximately 25 Mya.  © 2004 The Linnean Society of London, Biological Journal of the Linnean Society , 2004, 82 , 123–138.     

Sexual dimorphism of auditory function and structure in praying mantises (Mantodea; Dictyoptera)

Sexual dimorphism of tympanate auditory systems in insects has bees described in only a few taxonomically isolated cases. However, widespread sexual dimorphism occurs in the ultrasound-sensitive, midline ear of the praying mantis.
In dimorphic species, it is always the female mantis that shows a reduction in ultrasonic hearing. The dimorphism may be mild—a difference in tuning and small reduction in sensitivity—or extreme with no evidence of audition in the female. In all but the mildest cases, the reduction in hearing is accompanied by significant anatomical divergence from the male ear structure. Two distinct metathoracic groove ('ear') types are linked to hearing reduction in the females.
Anatomical evidence of auditory sexual dimorphism appears in 34% of the 183 mantis genera examined. The dimorphic genera are widely but non-uniformly distributed within three of the four largest mantis families.
Auditory sexual dimorphism is closely correlated with dimorphism in wing length. In general, mantises with functional wings have sensitive ultrasonic hearing while those with short wings do not. These findings support the hypothesis that ultrasonic hearing in mantises is part of a defensive system against attack by echolocating bats.     

A phylogeny of the families of fossil and extant tetraodontiform fishes (Acanthomorpha, Tetraodontiformes), Upper Cretaceous to Recent

A data matrix is presented of 210 morphological characters (mostly osteological, some external) for 20 extant taxa of the ten Recent families of tetraodontiform fishes and 36 fossil tetraodontiforms. The oldest of these are from the Upper Cretaceous (95 Mya); most are from the Lower to Middle Eocene (50–58 Mya). There are two outgroup taxa (a zeiform and a caproid). A cladistic analysis of this matrix for only the extant taxa produced two equally parsimonious trees that call into question the monophyly of some of the previously accepted major higher-level tetraodontiform clades. Inclusion in the analysis of the large number of available fossil taxa helps to resolve relationships between family level clades. The new phylogenetic hypothesis, together with stratigraphic and biogeographical data, is used to discuss scenarios of the origin and evolution of the major clades of the order.  © 2003 The Linnean Society of London, Zoological Journal of the Linnean Society , 2003, 139 , 565−617.     

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.     

Heterochrony in Tingidae (Insecta: Heteroptera): paedomorphosis and/or peramorphosis?

Tingidae (Heteroptera: Insecta) exhibit cephalic tubercles that present a very diverse shape in larvae but that are much simpler in adults. A phylogeny based on adult and last instar characters showed that these tubercles evolved independently from simple to complex states in two clades, and reversed from complex to simple in some taxa. These homoplasies are analysed in the light of ontogenetic sequences and interpreted as heterochronic events. The general trend of evolution of the cephalic tubercles in Tingidae is in mosaic, and could be generally peramorphic, with some isolated cases of paedomorphosis.  Journal compilation © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 93 , 71–80. No claim to original French government works.     

Nomenclatural changes in preparation for a World Rubiaceae Checklist

During the preparation of a World Rubiaceae Checklist , numerous unplaced taxa were encountered, including illegitimate and invalid names, and species for which generic placement is uncertain. In this contribution, 35 new combinations and 20 new names are proposed, and the names of three taxa are validated.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 157 , 115–124.     

Mate location, antennal morphology, and ecology in two praying mantids (Insecta: Mantodea)

The sensory systems employed by animals to locate potential mates are diverse. Among insects, chemical and acoustic signals are commonly used over long distances, with visual signals playing a role in close-range orientation and courtship. Within groups that exhibit a scramble competition mating system, selection on mate searching ability will be particularly strong. Clearly, aspects of the species ecology, such as habitat complexity and population density, will be crucial in the evolution of mate searching systems and sexual signals. Praying mantids exhibit both chemical and visual sexual signalling behaviour, and also vary in their ecology. This study employs scanning electron microscopy of antennal sensory morphology and behavioural assays to investigate the relative importance of chemical and visual signalling in two Australian praying mantid species: Pseudomantis albofimbriata and Ciulfina biseriata . As predicted, the high level of habitat complexity, low population density and strong male dispersal capability of P. albofimbriata corresponded to the use of airborne sex pheromones. Conversely, the open habitat, high population density, and poor dispersal of C. biseriata corresponded to a greater reliance on short-range visual cues for mate location.  © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 91 , 307–313.     

The fossil history of palms (Arecaceae) in Africa and new records from the Late Oligocene (28–27 Mya) of north-western Ethiopia

The African palm fossil record is limited but the data provide an outline of palm evolution from the Late Cretaceous through the Neogene. Pollen attributed to palms is reported from the Aptian (125–112 Mya), but the earliest unequivocal record in Africa is Campanian (83.5–70.6 Mya). Palms diversified 83.5–65.5 Mya and became widespread, although most records are from the west and north African coasts. Many taxa were shared between Africa and northern South America at that time, but a few were pantropical. Extirpations occurred throughout the Palaeogene, including a notable species turnover and decline at the Eocene–Oligocene boundary (33.9 Mya), a change that resulted in the elimination of nypoid palms from Africa. The Neogene plant macrofossil record is better sampled than the Palaeogene, although few palms are documented. Thus, the low diversity of African palms today is more likely the result of Palaeogene, rather than Neogene extinctions. Newly discovered palm fossils of leaves, petioles and flowers from the Late Oligocene (27–28 Mya) of north-western Ethiopia document the abundance and dominance of palms in some communities at that time. The fossils represent the earliest records of the extant genera Hyphaene (Coryphoideae) and Eremospatha (Calamoideae).  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 69–81.     

Microsatellite DNA and behavioural studies provide evidence of host-mediated speciation in Myzus persicae (Hemiptera: Aphididae)

The fossil record of mammals records a major interchange of northern and southern faunas in the New World, upon closure of the Panamanian isthmus approximately 3 Mya, termed the Great American Biotic Interchange (GABI). Due to their poor preservation in the fossil record, the degree of participation of birds in this interchange remains largely unknown. A phylogeny for wrens of the genus Campylorhynchus (Aves: Passeriformes) was reconstructed using DNA sequences from the mitochondrial control region and cytochrome b gene. This phylogeny, in combination with biogeographical inference and molecular clock methods, allows estimates of the importance of Late Pliocene interchange to the history of the group. Biogeographical reconstructions and divergence date estimates suggest that the genus began diversification in North America prior to closure of the Panamanian isthmus, consistent with a hypothesized North American origin for the family Troglodytidae. These reconstructions are consistent with pre-GABI dispersal of at most a single Campylorhynchus lineage into South America, with subsequent dispersal of additional lineages, probably across the fully formed isthmus. Increased sampling of avian taxa with widespread New World distributions will continue to clarify the timing and direction of continental interchange.  © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 90 , 687–702.     

Phylogenetic analysis of non-stereotyped behavioural sequences with a successive event-pairing method

A new method is proposed which uses transitions among acts in non-stereotyped behavioural sequences as phylogenetic characters. This method is derived from the event-pairing method designed for the phylogenetic study of developmental sequences and from ethological analyses of transition matrices. It is applied to study the phylogenetic relationships within a well-known group, the presocial Zetoborinae cockroaches. The analysis is carried out with three data sets: a behavioural data set with transitions among acts in behavioural dyadic sequences, together with morphological and molecular data sets. Non-stereotyped behaviour proved to be phylogenetically informative and to display low homoplasy. This new method opens an avenue for studying the evolution of behaviour in the framework of phylogenetic analysis, which was restricted until now to the study of stereotyped sequences and/or isolated features involved in courting or building activities.  © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 94 , 853–867.     

Global stingless bee phylogeny supports ancient divergence,vicariance, and long distance dispersal

Stingless bees (Meliponini) are one of only two highly eusocial bees, the other being the well studied honey bee (Apini). Unlike Apini, with only 11 species in the single genus Apis, stingless bees are a large and diverse taxon comprising some 60 genera, many of which are poorly known. This is the first attempt to infer a phylogeny of the group that includes the world fauna and extensive molecular data. Understanding the evolutionary relationships of these bees would provide a basis for behavioural studies within an evolutionary framework, illuminating the origins of complex social behaviour, such as the employment of dance and sound to communicate the location of food or shelter. In addition to a global phylogeny, we also provide estimates of divergence times and ancestral biogeograhic distributions of the major groups. Bayesian and maximum likelihood analyses strongly support a principal division of Meliponini into Old and New World groups, with the Afrotropical+Indo‐Malay/Australian clades comprising the sister group to the large Neotropical clade. The meliponine crown clade is inferred to be of late Gondwanan origin (approximately 80 Mya), undergoing radiations in the Afrotropical and Indo‐Malayan/Australasian regions, approximately 50–60 Mya. In the New World, major diversifications occurred approximately 30–40 Mya. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99 , 206–232.     

Correlations between auditory structures and hearing sensitivity in non‐human primates

Primates show distinctions in hearing sensitivity and auditory morphology that generally follow phylogenetic patterns. However, few previous studies have attempted to investigate how differences in primate hearing are directly related to differences in ear morphology. This research helps fill this void by exploring the form‐to‐function relationships of the auditory system in a phylogenetically broad sample of non‐human primates. Numerous structures from the outer, middle, and inner ears were measured in taxa with known hearing capabilities. The structures investigated include the overall size and shape of the pinna, the areas of the tympanic membrane and stapedial footplate, the masses and lever arm lengths of the ossicles, the volumes of the middle ear cavities, and the length of the cochlea. The results demonstrate that a variety of auditory structures show significant correlations with certain aspects of hearing (particularly low‐frequency sensitivity). Although the majority of these relationships agree with expectations from auditory theory, some traditional (and possibly outdated) ideas were not supported. For example, the common misconception that higher middle ear transformer ratios (e.g., impedance transformer ratio) result in increased hearing sensitivity was not supported. Although simple correlations between form and function do not necessarily imply causality, the relationships defined in this study not only increase our understanding of auditory patterns in extant taxa but also lay the foundation to begin investigating the hearing in fossil primates. J. Morphol., 2010. © 2009 Wiley‐Liss, Inc.     

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.     

Lung-based hearing in an “earless” anuran amphibian

The mechanisms of hearing in the fire-bellied toad Bombina orientalis, an “earless” species of amphibian that lacks a standard tympanic middle ear, were studied using laser Doppler vibrometric and neurophysiological techniques. Laser vibrometry demonstrated that the anterolateral body wall overlying the lung is much more responsive to sound than the lateral head surface overlying the inner ear. Covering the lateral body wall with silicone grease dramatically decreased auditory midbrain sensitivity at all frequencies examined, elevating thresholds by 20–25 dB. Filling the lungs with oxygenated saline produced similar decrements in hearing sensitivity, and both manipulations strongly suggest that the lung is the primary route of sound reception in this species. The precise route of transfer of sound energy from the body wall and lungs to the inner ear remains unclear. The lung-based hearing system of “earless” fire-bellied toads may represent the retention of the first auditory mechanism used by early tetrapod vertebrates for detection of airborne sound. Accepted: 10 December 1998     

Bats and moths: what is there left to learn?

Abstract.  Over 14 families of moths have ears that are adapted to detect the ultrasonic echolocation calls of bats. On hearing a bat, these moths respond with an escape response that reduces their chances of being caught. As an evolutionary response, bats may then have evolved behavioural strategies or changes in call design to overcome the moth's hearing. The nature of this interaction is reviewed. In particular, the role of the echolocation calls of bats in the shaping of the structure, neurophysiology and behavioural responses of moths is discussed. Unresolved issues, such as the structural complexity of the moth's auditory system, the nature of temporal integration and the role of the non-auditory B cell, are described. Issues in which the interactions between bats and moths may be of more general interest to biologists, such as noise filtering within the central nervous system, protean behaviours and coevolution between predator and prey, are also discussed. The interaction between bats and moths has much to interest general biologists, and may provide a useful model in understanding the neurophysiological basis of behaviour, including protean escape behaviours. The validity of the term coevolution as applied to this system is discussed, as there is no doubt that the auditory system of moths is a response to the echolocation calls of bats, although the evolutionary response of bats to moths is more ambiguous.     

Neuroethology of ultrasonic hearing in nocturnal butterflies (Hedyloidea)

Nocturnal Hedyloidea butterflies possess ultrasound-sensitive ears that mediate evasive flight maneuvers. Tympanal ear morphology, auditory physiology and behavioural responses to ultrasound are described for Macrosoma heliconiaria, and evidence for hearing is described for eight other hedylid species. The ear is formed by modifications of the cubital and subcostal veins at the forewing base, where the thin (1–3 μm), ovoid (520 × 220 μm) tympanal membrane occurs in a cavity. The ear is innervated by nerve IIN1c, with three chordotonal organs attaching to separate regions of the tympanal membrane. Extracellular recordings from IIN1c reveal sensory responses to ultrasonic (>20 kHz), but not low frequency (<10 kHz) sounds. Hearing is broadly tuned to frequencies between 40 and 80 kHz, with best thresholds around 60 dB SPL. Free flying butterflies exposed to ultrasound exhibit a variety of evasive maneuvers, characterized by sudden and unpredictable changes in direction, increased velocity, and durations of ∼500 ms. Hedylid hearing is compared to that of several other insects that have independently evolved ears for the same purpose-bat detection. Hedylid hearing may also represent an interesting example of evolutionary divergence, since we demonstrate that the ears are homologous to low frequency ears in some diurnal Nymphalidae butterflies.     

Markedly discordant mitochondrial DNA and allozyme phylogenies of tube-nosed fruit bats, Nyctimene, at the Australian–Oriental biogeographical interface

Australo-Papuan tube-nosed fruit bats of the genus Nyctimene reach their most westerly distribution on the island archipelagos of eastern Indonesia. A recent morphological examination indicates three species occur on Moluccan islands. Both allozyme electrophoresis and mitochondrial DNA (mtDNA) sequencing reveal there are only two species present, Nyctimene cephalotes and Nyctimene albiventer , but there is considerable disparity between the results obtained from the two genetic data sets. Allozyme data indicate N. albiventer occurs on Wokam, which sits on the Australian continental shelf and was joined to Australo-Papua during the last glacial maximum, and N. cephalotes on the other Moluccan islands, all of which are off the continental shelf. Divergence of these two species is dated at approximately 1.5 Mya. By contrast, the mtDNA gene tree shows two deep clades, one containing all specimens from Wokam and Yamdena, and the second all the specimens from the other islands. This especially marked incongruence between the two genetic data sets is ascribed to either a single introgression event of N. albiventer mtDNA into N. cephalotes on Yamdena at around 100 000 ya or lineage sorting of very old mtDNA lineages that coalesce a rather long time before the speciation event. These results highlight that caution should be exercised when relying on mtDNA as barcodes in species taxonomy. The continental-associated N. albiventer on Wokam has higher levels of allozyme heterozygosity and mtDNA nucleotide diversity than the N. cephalotes populations occurring on the more remote islands, indicating that this colonizing species has experienced bottlenecks and/or a low effective population size since speciation.  © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 93 , 589–602.