Isolation and characterization of highly polymorphic microsatellite loci for the garden tiger moth Arctia caja (Lepidoptera: Arctiidae)

A set of microsatellite markers was isolated from Arctia caja, a species that has been declining in UK for several decades. As has been found with other Lepidoptera species, this proved to be a difficult task. Eight enriched libraries identified 103 positive clones, and these yielded only seven polymorphic microsatellites. Allelic diversity ranged from 10 to 23 alleles per locus in a population of 30 individuals. Significant heterozygosity deficits were shown by three of these loci, presumably due to null alleles. The remaining four loci were in Hardy–Weinberg equilibrium and will be used to investigate the population genetic structure of A. caja.     

Isolation and characterization of eight microsatellite loci for the study of gene flow between Testudo marginata and Testudo weissingeri (Testudines: Testudinidae)

The taxonomic status of the Greek Testudo species, marginated tortoise (Testudo marginata Schoepff, 1793) and dwarf marginated tortoise (Testudo weissingeri Bour, 1995), is controversed. In order to study the gene flow among these Greek Testudo species, eight polymorphic microsatellite markers were characterized and screened for 32 individuals. The number of alleles observed per locus ranged from two to 19. Observed heterozygosities varied from 0.235 to 0.830. These microsatellite loci were also successfully tested on seven closely related species of Testudinidae. This set of microsatellites offers an efficient tool to investigate genetic differentiation among testudinid species.     

The effect of body condition on the timing and success of breeding in Little Penguins Eudyptula minor

We studied the effect of parental body condition on the breeding biology of Little Penguins Eudyptula minor . Daily attendance patterns and body mass were recorded using an Automated Penguin Monitoring System, which collected arrival and departure masses for approximately 200 breeding birds over the 2000 and 2001 breeding seasons. Breeding success varied between the two years; 2000 was a year of average breeding success (fledging 1.07 chicks per pair), and 2001 a year of poor breeding success (fledging 0.53 chicks per pair). In both years, adult body condition (body mass divided by flipper length) increased significantly prior to laying. The laying period began over a month later in 2000 than in 2001, and birds in 2000 exhibited significantly better body condition at laying. However, the mean laying dates in 2000 were less variable than in the 2001 breeding season. Body condition appeared to influence both the time of breeding and breeding synchrony in Little Penguins. Breeding success was correlated with adult body condition at incubation in 2000 but not in 2001, indicating that success was not solely influenced by adult body condition at incubation.     

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.     

Oviposition decreased in response to enriched water: a field study of the pitcher-plant mosquito, Wyeomyia smithii

Abstract.  1. Environmental cues are known to influence oviposition behaviour in mosquitoes, with important consequences for larval survival and insect population dynamics. Enriched microhabitats have been shown to be preferred oviposition sites.
2. In a field experiment designed to determine whether ovipositing mosquitoes are sensitive to different levels of nutrient enrichment, new pitcher-plant ( Sarracenia purpurea ) leaves were opened and enriched with 0, 2, or 20 dead ants, and the number of pitcher-plant mosquito ( Wyeomyia smithii ) larvae resulting from subsequent oviposition were measured.
3. Oviposition rates were higher in leaves with low levels of enrichment (0 and 2 ants per leaf), although larval development was enhanced at the highest enrichment level.
4. Results suggest that, although these mosquito larvae are nutrient limited, ovipositing females preferentially avoid highly enriched leaves. This counterintuitive result may be due to low oxygen concentrations or a masked cue in enriched leaves, and contrasts with other oviposition studies.     

The radiation of red colobus monkeys (Primates,Colobinae): morphological evolution in a clade of endangered African primates

Red colobus monkeys are a group of African monkeys that include some of the most endangered primate populations. Despite urgently needing to understand the importance of particular populations for preserving the biodiversity of this lineage, their evolutionary relationships remain poorly understood, and their taxonomy is unstable, and often enigmatic. Data on behaviour, ecology, genetics, and morphology are thus strongly needed to address taxonomic issues that are not only relevant for primatologists, but also for conservation biologists. In this study, we investigated the morphological diversity and evolution of red colobus by examining the cranial variation of 369 individuals from most living populations. Crania were measured using a set of 64 anatomical landmarks, and were analysed using geometric morphometric methods for the study of three‐dimensional landmark coordinates. We found significant differences among most of the populations traditionally described on the basis of pelage colour and geographic distribution. However, differences tended to be smaller within biogeographic assemblages, which might be related to mountain refugia during periods of forest contraction in the Pleistocene.We also found a tendency towards large taxonomic distances, which suggested that populations might have originated earlier than has been traditionally thought, a result congruent with a recent molecular phylogenetic analysis. However, the distinctive forms of East African relict populations might be related to an acceleration of morphological evolution in small peripheral isolates, under strong selective pressures. This indicates that small and isolated populations, which are also the most endangered ones, might indeed be unique representatives of the red colobus radiation, and hence contribute to its biodiversity significantly. However, in‐ depth morphological studies of red colobus, particularly those in peripheral populations that tend to be rare in the wild, as well as in museum collections, is hampered by a paucity of data. In these cases, populations might be extinct before primatologists and conservationsts can even appreciate what was lost.     

A 17‐element conodont apparatus from the Soom Shale Lagerstätte (Upper Ordovician), South Africa

Abstract:  Natural assemblages of a new conodont taxon, Notiodella keblon, from the Upper Ordovician Soom Shale Lagerstätte of South Africa contain 17 elements. This is the first time that a 17‐element apparatus plan has been unequivocally demonstrated in conodonts. The apparatus comprises paired P₁, P₂, P₃, M, S₁, S₂, S₃ and S₄ elements and an unpaired, axial S₀ element and provides a new template for use in the reconstruction of apparatuses from the collections of dispersed elements, particularly for those with icrion‐bearing P₁ elements and perhaps for other balognathids.     

Among‐colony synchrony in the survival of Common Guillemots Uria aalge reflects shared wintering areas

Spatiotemporal variation in survival may be an important driver of multi‐population dynamics in many wild animal species, yet few scientific studies have addressed this issue, primarily due to a lack of sufficiently comprehensive and detailed datasets. Synchrony in survival rates among different, often distant, subpopulations appears to be common, caused by spatially correlated environmental conditions or by movement of animals from different sites such that their ranges overlap. Many seabird populations are effectively isolated during the breeding season because colonies are widely separated, but over the winter, birds disperse widely and there may be much mixing between different populations. The non‐breeding season is also the period of main mortality for seabirds. Using mark–recapture and ring‐recovery data, we tested for spatial, temporal and age‐related correlations in survival of Common Guillemots Uria aalge among three widely separated Scottish colonies that have varying overlap in their overwintering distributions. Survival was highly correlated over time for colonies/age‐classes sharing wintering areas and, except in 2004, was essentially uncorrelated for those with separate wintering areas. These results strongly suggest that one or more aspects of the winter environment are responsible for spatiotemporal variation in survival of British Guillemots, and provide insight into the factors driving large‐scale population dynamics of the species.     

Weak large‐scale population genetic structure in a philopatric seabird,the European Shag Phalacrocorax aristotelis

Quantifying population genetic structure is fundamental to testing hypotheses regarding gene flow, population divergence and dynamics across large spatial scales. In species with highly mobile life‐history stages, where it is unclear whether such movements translate into effective dispersal among discrete philopatric breeding populations, this approach can be particularly effective. We used seven nuclear microsatellite loci and mitochondrial DNA (ND2) markers to quantify population genetic structure and variation across 20 populations (447 individuals) of one such species, the European Shag, spanning a large geographical range. Despite high breeding philopatry, rare cross‐sea movements and recognized subspecies, population genetic structure was weak across both microsatellites and mitochondrial markers. Furthermore, although isolation‐by‐distance was detected, microsatellite variation provided no evidence that open sea formed a complete barrier to effective dispersal. These data suggest that occasional long‐distance, cross‐sea movements translate into gene flow across a large spatial scale. Historical factors may also have shaped contemporary genetic structure: cluster analyses of microsatellite data identified three groups, comprising colonies at southern, mid‐ and northern latitudes, and similar structure was observed at mitochondrial loci. Only one private mitochondrial haplotype was found among subspecies, suggesting that this current taxonomic subdivision may not be mirrored by genetic isolation.     

Long-lasting effects on nitrogen cycling 12 years after treatments cease despite minimal long-term nitrogen retention

Atmospheric deposition of biologically active nitrogen (N) has increased dramatically over the past 60 years, with far-reaching impacts on the structure and function of many ecosystems. Much research has examined the initial impacts of N enrichment; however, few studies have been multidecadal, and even fewer long-term studies have examined the longevity of N-induced impacts on N cycling after inputs cease. Here, we address this gap by reporting the state of key N pools and fluxes in a Minnesota grassland for plots that received N addition for 10 years and then none for 12 years, in comparison with plots that received annual N treatment for the entire 22 years. We found weak evidence for long-term N retention in plots that ceased receiving treatment; and in plots that continued to receive N over the 22-year period, retention that was high after 12 years (50–100% of inputs) was greatly reduced after 22 years (to 15%). In spite of this, net N mineralization rates remained elevated in plots that ceased receiving treatment 12 years prior, likely because N-rich litter maintained higher N-cycling rates. These results suggest (1) some systems do not retain much deposited N, with potentially large impacts on downstream habitats; (2) the previously reported high retention efficiencies for this and many other terrestrial ecosystems may be relatively short-lived as N sinks become saturated over time; and (3) the effects of even small amounts of retained N in N-limited environments may be particularly long-lasting. In total, these findings highlight the importance of long-term studies in evaluating the impacts of chronic N deposition to ecosystems, and urge additional research examining dynamics following N cessation to evaluate the reversibility of these impacts.