Lost in translation – a history of systematic confusion and comments on the type species of Squalodon and Patriocetus (Cetacea,Odontoceti)

Abstract: The two odontocete taxa Squalodon grateloupii and Patriocetus ehrlichii, both the type species of their respective genera, have been at the centre of a great deal of taxonomic confusion. Originally regarded to be conspecific, these two taxa have been the subject of a bewildering taxonomic debate lasting for more than a century, which recently led to the suggestion to abandon these widely used names and replace S. grateloupii with the similar, yet independently and later proposed name S. gratelupi as the type species of Squalodon. Here, we attempt to summarise the events leading to the current confused situation in the hope of resolving this issue once and for all and argue that the name Squalodon grateloupii, as originally proposed, should be reinstated.     

Feeding innovations and parasitism in birds

The rate of behavioural innovation, such as opportunistic feeding innovation, may facilitate adaptation to novel environments. Because parasites may affect how their hosts adopt novel means of resource acquisition, or because opportunistic behaviours may involve the risk of being exposed to a large parasite fauna, we hypothesize an evolutionary link between the rate of feeding innovations and parasitism. We investigated the phylogenetic relationship between relative frequency of feeding innovations (adjusted for research effort and population size) and relative size of immune defense organs (as a relative measure of parasite-mediated selection) and the prevalence of blood parasites in birds. Using generalized least squares models, we found that species with relatively large bursa of Fabricius, thymus, and spleen had higher rates of feeding innovations than species with small immune defense organs. Similarly, there was a positive interspecific association between feeding innovation and haematozoa prevalence. These relationships were not confounded by migration, relative brain size, geographical distribution, and male plumage brightness. Analyses of causality relying on evolutionary modelling of discrete variables and path analysis suggest that increasing rate of feeding innovation may place species under intense selection due to parasitism. Therefore, behavioural adaptation by feeding innovation seems to have consequences for the coevolutionary arm race between parasites and hosts.  © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 90 , 441–455.     

Sexually dimorphic gall structures correspond to differential phytohormone contents in male and female wasp larvae

Sexually dimorphic galls are rare among gall‐inducing insects and the reason for their occurrence is unknown. The pteromalid wasp Trichilogaster acaciaelongifoliae, which induces galls on Acacia longifolia, is one such species. In the present study, the anatomical and physiological attributes of male and female galls of T. acaciaelongifoliae are examined and compared. Histological preparations are used to characterize anatomical differences between male and female gall chambers. Bioassays, high‐performance liquid chromatography‐mass spectrometry and an enzyme immunoassay are used to measure concentrations of auxin and cytokinin in normal buds, galled tissues, and larvae of both sexes. Female chambers are found to be 3.3‐fold larger, and are associated with 1.5‐fold more storage tissue and 3.5‐fold more vascular tissues than male chambers. Tissues from female chambers induce stronger cytokinin‐like bioactivity than tissues from male chambers. Female larvae have considerably higher concentrations of cytokinin free bases, ribosides, glucosides and monophosphates than male larvae; higher auxin‐like bioactivity than in normal or galled plant tissues; and almost twice the concentration of auxin than male larvae. Both male and female larvae contain much higher auxin concentrations than either galled or normal plant tissues. These findings suggest that differing levels of phytohormones are involved in the development of sexual dimorphism of gall structures in this species.     

Nitrogen aboveground turnover and soil stocks to 8 m depth in primary and selectively logged forest in southern Amazonia

Extensive areas of Amazonia undergo selective logging, modifying forest structure and nutrient cycles. Anthropogenic‐accelerated rates of nitrogen (N) turnover could increase N loss and affect regeneration, carbon sequestration and timber production. We quantified leaf area reduction, canopy opening and downed biomass and resultant N flux from reduced impact logging (RIL) activities. We compared canopy reduction, surface soil moisture and nitrate to 8 m depth between logged gaps and intact primary forest to determine if logging activities increase subsoil nitrate. To test long‐term logging effects, we evaluated surface N stocks along a 12‐year postlogging chronosequence. At the harvest rate of 2.6 trees ha^?1, total N additions in logging gaps, including leaves and wood from felled crowns (24.8 kg N ha^?1) and other killed trees (41.9 kg N ha^?1), accounted for over 80% of the total N addition to aboveground necromass from all logging activities (81.9 kg N ha^?1). Despite this N turnover by logging, belowground nitrate storage to 8 m depth did not differ between logging gaps and primary forest at the low harvest rate and disturbance intensity of this study. Soil water depletion also did not differ between gaps and primary forest over 1 year, indicating the impact on belowground inorganic N was low. Compared with primary forest, nitrate concentrations to 8 m depth in logging gaps were only significantly higher at 60–100 cm, suggesting some N redistribution beyond the bulk of the fine roots in logging gaps. Extrapolated to the Amazon Basin scale, we provide a conservative estimate that logging damage and bole export under RIL would turn over 0.14 ± 0.07 to 0.23 ± 0.12 Tg N yr^?1 based on 1999–2002 selective logging rates. Greater damage during conventional selective logging would cause higher N turnover throughout the Amazon Basin than our results based on RIL.     

The earliest myodocopes: ostracodes from the late Ordovician Soom Shale Lagerstätte of South Africa

The late Ordovician Soom Shale Lagerstätte of South Africa has yielded Myodoprimigenia fistuca n. gen. and n. sp., the earliest and only known Ordovician occurrence of myodocopes, one of the major groups of ostracodes. M. fistuca is a likely sister group of the Upper Silurian 'cypridinid' myodocopes and allied forms. It had a thin, lightly mineralized and flexible shell with microstructures resulting from in vivo calcification processes. It probably fed on cephalopod carrion, thus extending evidence for a carnivorous scavenging lifestyle in ostracodes back by 200  Ma. The species was probably nektobenthic and thus consistent with the notion that the origin of the late Silurian pelagic myodocopes - and therefore of pelagic ostracodes - is to be charted in a benthic to pelagic ecological shift in the group.     

CLARIFYING APPEALS TO DIGNITY IN MEDICAL ETHICS FROM AN HISTORICAL PERSPECTIVE

Over the past few decades the concept of (human) dignity has deeply pervaded medical ethics. Appeals to dignity, however, are often unclear. As a result some prefer to eliminate the concept from medical ethics, whereas others try to render it useful in this context. We think that appeals to dignity in medical ethics can be clarified by considering the concept from an historical perspective. Firstly, on the basis of historical texts we propose a framework for defining the concept in medical debates. The framework shows that dignity can occur in a relational, an unconditional, a subjective and a Kantian form. Interestingly, all forms relate to one concept since they have four features in common: dignity refers, in a restricted sense, to the 'special status of human beings'; it is based on essential human characteristics; the subject of dignity should live up to it; and it is a vulnerable concept, it can be lost or violated. We argue that being explicit about the meaning of dignity will prevent dignity from becoming a conversation-stopper in moral debate. Secondly, an historical perspective on dignity shows that it is not yet time to dispose of dignity in medical ethics. At least Kantian and relational dignity can be made useful in medical ethics.     

Extensive diversification of pebblesnails (Lithoglyphidae: Fluminicola) in the upper Sacramento River basin, northwestern USA

Mitochondrial DNA sequences from the cytochrome c oxidase subunit I (COI) and cytochrome b (cytb) genes were obtained from the nine extant, previously described species of the northwestern North American freshwater gastropod genus Fluminicola (commonly known as pebblesnails) and from a large number of taxonomically undescribed populations of these animals from the upper Sacramento River basin, California and Oregon, which is composed of the Sacramento River headwaters, and the McCloud and Pit Rivers. Phylogenetic analyses of separate and combined molecular datasets yielded well‐supported and largely congruent trees delineating 13 genetically divergent and morphologically distinctive upper Sacramento basin lineages, which we describe as new species. These include two groups of closely related and geographically proximal species that are further united by unique radular or shell features. Most of these novelties have narrow geographical distributions and are restricted to headspring areas, whereas several are more wide ranging and typically occupy larger, well‐integrated habitats. The highly endemic fauna of upper Sacramento River pebblesnails is not a single species flock, but instead a polyphyletic assemblage spread among four separate clades. Our phylogeny, together with the application of a COI molecular clock for Fluminicola, suggests that upper Sacramento River clades originated as a result of late Neogene separation of this basin from neighbouring regions (northwestern Great Basin, Klamath River basin), which is consistent with previous biogeographical hypotheses based on the distributions of fishes. The upper Sacramento River pebblesnails evolved in association with the complex late Cenozoic history of regional landscape and drainage and diversification was also facilitated by the invasion of and adaptation to insular spring habitats. Our findings are consistent with the generally limited dispersal ability and geologically ancient (mid‐Tertiary) age of this genus and imply that other portions of northwestern North America may also harbour a large number of undescribed pebblesnail species. Journal compilation © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society, 2007, 149 , 371–422. No claim to original US government works.     

Climate change causes rapid changes in the distribution and site abundance of birds in winter

Detecting coherent signals of climate change is best achieved by conducting expansive, long‐term studies. Here, using counts of waders (Charadrii) collected from ca. 3500 sites over 30 years and covering a major portion of western Europe, we present the largest‐scale study to show that faunal abundance is influenced by climate in winter. We demonstrate that the ‘weighted centroids’ of populations of seven species of wader occurring in internationally important numbers have undergone substantial shifts of up to 115 km, generally in a northeasterly direction. To our knowledge, this shift is greater than that recorded in any other study, but closer to what would be expected as a result of the spatial distribution of ecological zones. We establish that year‐to‐year changes in site abundance have been positively correlated with concurrent changes in temperature, but that this relationship is most marked towards the colder extremities of the birds' range, suggesting that shifts have occurred as a result of range expansion and that responses to climate change are temperature dependent. Many attempts to model the future impacts of climate change on the distribution of organisms, assume uniform responses or shifts throughout a species' range or with temperature, but our results suggest that this may not be a valid approach. We propose that, with warming temperatures, hitherto unsuitable sites in northeastern Europe will host increasingly important wader numbers, but that this may not be matched by declines elsewhere within the study area. The need to establish that such changes are occurring is accentuated by the statutory importance of this taxon in the designation of protected areas.