Lack of Mother—Offspring Relationships in White-Tailed Deer Capture Groups

ABSTRACT Behavioral studies of white-tailed deer (Odocoileus virginianus) often assign mother-offspring relationships based on common capture of juveniles with adult deer, assuming that fawns associate closely with mothers. We tested this assumption using genetic parentage to assess mother-offspring relationships within capture groups based on data from 10 polymorphic microsatellite loci. At the 80% confidence level, we assigned maternity to 43% and 51% of juveniles captured with an adult female in 2 respective study areas. Capture with their mother did not differ by sex of juveniles in either study area, and limiting our analysis to capture groups that most represent family groups (i.e., one ad F with 1–3 juv) did not increase maternity assignment (35%). Our results indicate that common capture may be a poor indicator of mother-offspring relationships in many field settings. We recommend genetic verification of family relationships.     

Complex trait differentiation between host-populations of the pea aphid Acyrthosiphon pisum (Harris): implications for the evolution of ecological specialisation

Variation in traits affecting preference for, and performance on, new habitats is a key factor in the initiation of ecological specialisation and adaptive speciation. However, habitat and resource use also involves other traits whose influence on ecological and genetic divergence remains poorly understood. In the present study, we investigated the extent of variation of life-history traits among sympatric populations of the pea aphid Acyrthosiphon pisum , which shows several host races that are specialised on various plants of the family Fabaceae plants and is an established model for ecological speciation. First, we assessed the community structure of microbial partners within host populations of the pea aphid. The effect of these microbes on host fitness is uncertain, although there is growing evidence that they may modulate various important adaptive traits of their host such as plant utilisation and resistance against natural enemies. Second, we performed a multivariate analysis on several ecologically relevant features of host populations recorded in the present and previous studies (including microbial composition, colour morph, reproductive mode, and male dispersal phenotype), enabling the identification of correlations between phenotypic traits. We discuss the ecological significance of these associations of traits in relation to the habitat characteristics of pea aphid populations, and their consequences for the evolution of ecological specialisation and sympatric speciation.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 97 , 718–727.     

VISUAL CHARACTERIZATION OF THE ESTHETIC QUALITY OF THE ROSEBUSH

Since its introduction into the analysis of foodstuffs, sensory analysis has been applied in several contexts. This work seeks to widen the field of sensory analysis to include ornamental plants and to characterize their esthetic quality. Using the rosebush as a plant model, an attribute generation protocol is proposed in order to develop a conventional profile of such products. Further to statistical treatments aiming to verify the unambiguity, discrimination and independence of these attributes, a reduced list of 18 attributes has been set up. These attributes make up the very core of the conventional profiling studies currently undertaken .

PRACTICAL APPLICATIONS

The generation of a list of attributes that is not too long, in order to describe plants as exhaustively as possible, is one of the first steps of extending sensory analysis methods to ornamental horticulture. This list will be used to train a panel of assessors to characterize the rosebush.
Two applications are in progress. The first application consists of evaluating the impact of nitrogen nutrition on the visual quality of the rosebush. The second has the objective of determining which characteristics influence consumer preferences.     

The origins and diversification of C4 grasses and savanna-adapted ungulates

C₄ grasses constitute the main component of savannas and are pervasive in other dry tropical ecosystems where they serve as the main diet for grazing animals. Among potential factors driving C₄ evolution of grasses, the interaction between grasses and grazers has not been investigated. To evaluate if increased grazing pressure may have selected for higher leaf silica production as the grasses diverged, we reconstructed the phylogeny of all 800 genera of the grass family with both molecular (combined multiplastid DNA regions) and morphological characters. Using molecular clocks, we also calculated the age and number of origins of C₄ clades and found that shifts from C₃ to C₄ photosynthesis occurred at least 12 times starting 30.9 million years ago and found evidence that the most severe drop in atmospheric carbon dioxide in the late Oligocene (between 33 and 30 million years ago) matches the first origin of C₄ photosynthesis in Chloridoideae. By combining fossil and phylogenetic data for ungulates and implementing a randomization procedure, our results showed that the appearance of C₄ grass clades and ungulate adaptations to C₄-dominated habitats match significantly in time. An increase of leaf epidermal density of silica bodies was found to correspond to postulated shifts in diversification rates in the late Miocene [24 significant shifts in diversification ( P <0.05) were detected between 23 and 3.7 million years ago]. For aristidoid and chloridoid grasses, increased grazing pressure may have selected for a higher leaf epidermal silica production in the late Miocene.     

Similar breakdown rates and benthic macroinvertebrate assemblages on native and Eucalyptus globulus leaf litter in Californian streams

1. Eucalyptus globulus, a tree species planted worldwide in many riparian zones, has been reported to affect benthic macroinvertebrates negatively. Although there is no consensus about the effects of Eucalyptus on aquatic macrobenthos, its removal is sometimes proposed as a means of ecological restoration. 2. We combined the sampling of macroinvertebrates with measurement of the colonisation of leaf packs in mesh bags, to examine the effects of riparian Eucalyptus and its litter on benthic macroinvertebrates in three small streams in California, U.S.A. Each stream included one reach bordered by Eucalyptus (E‐site) and a second bordered by native vegetation (N‐site). 3. The macrobenthos was sampled and two sets of litter bags were deployed at each site: one set with Eucalyptus litter (Euc‐bags) and one with mixed native tree litter (Nat‐bags) containing Quercus, Umbellularia, Acer and Alnus. Bags were exposed for 28, 56 and 90 days and this experiment was repeated in the autumn, winter and spring to account for effects of changing stream flow and insect phenology. 4. Litter input (average dry mass: 950 g m^?2 year^?1 in E‐sites versus 669 g m^?2 year^?1 in N‐sites) was similar, although in‐stream litter composition differed between E‐ and N‐sites. Litter broke down at similar rates in Euc‐bags and Nat‐bags (0.0193 day^?1 versus 0.0134 day^?1), perhaps reflecting the refractory nature of some of the leaves of the native trees (Quercus agrifolia). 5. Summary metrics for macroinvertebrates (taxon richness, Shannon diversity, pollution tolerance index) did not differ significantly between the E and N sites, or between Euc‐bags and Nat‐bags. No effect of exposure time or site was detected by ordination of the taxa sampled. However, distinct seasonal ordination clusters were observed in winter, spring and autumn, and one of the three streams formed a separate cluster. 6. The presence of Eucalyptus was less important in explaining the taxonomic composition of the macrobenthos than either ‘season’ or ‘stream’. Similarly, these same two factors (but not litter species) also helped explain the variation in leaf breakdown. We conclude that patches of riparian Eucalyptus and its litter have little effect on stream macrobenthos in this region.     

Geographical variation, sex and age in Great Bittern Botaurus stellaris using coloration and morphometrics

Biometrics, plumage and bare-part colour of 87 Great Bitterns Botaurus stellaris from the UK, France, Italy, Poland and Belarus, of known sex (sexed by behaviour, DNA or dissection), were analysed to provide reliable sexing and ageing criteria for this little-known species, and to investigate geographical variation in biometrics. Four parameters were analysed: bill length, tarsus, wing length and body weight. We found little (though significant) geographical variation across Europe, but this was not clinal and we cannot exclude variation in measurement technique among observers. Males were significantly larger than females for all biometric parameters: a discriminant function based on these parameters was able to sex correctly all individuals. Body weight varied with season, especially for males. During the breeding period, lore colour was also a reliable sex-criterion. Ageing proved more difficult and required a combination of iris colour (which darkens with age) and flight-feather moult. From this, the largest sample size of known-age Great Bitterns, we conclude that most previously published criteria for age determination of this species were wrong.     

A NEW PCR METHOD OF CHARACTERIZING SEAFISH FRESHNESS

Objective criteria used to assess the fish freshness in the laboratory are currently inadequate. During contamination of muscle tissue, bacteria reduce trimethylamine oxide (TMAO) to trimethylamine (TMA) in the absence of oxygen. Based on this reaction, we envisaged a new approach and have developed and optimized a PCR method which targets the tor A gene sequence that encodes TMAO reductase. We applied this method to two fish species (Whiting (Merlangus merlangus) and Pouting (Gadus luscus)) during monitoring of spoilage, in parallel with assay of TVBN and enumeration of total aerobic flora. The PCR results tally with the chemical and microbiological findings. Used in quantitative PCR, this method could characterize fish freshness.     

SYNCARID CRUSTACEANS FROM THE MONTCEAU LAGERSTÄTTE (UPPER CARBONIFEROUS; FRANCE)

Abstract: Key aspects of the morphology, autecology, systematics and taphonomy of the crustacean syncarids from the Montceau Lagerstätte (Upper Carboniferous, Stephanian B; France) are presented. Palaeocaris secretanae is the most abundant faunal element of the Montceau biota and shows striking morphological similarities with Palaeocaris typus from the Mazon Creek Lagerstätte (Westphalian D; Illinois, USA). Palaeocaris secretanae was a shrimp‐like animal with a short head (no head shield), large mandibles, 14 trunk segments (the first one being reduced) and a fan‐like caudal termination. Both the body and the appendage design indicate abilities for crawling on the substratum (slender endopods) and for escape reaction (uropodal fan, pleonal flexibility), although swimming activities may have been reduced (trunk appendages with small flap‐like exopods). Details of the appendages involved in feeding, e.g. mandibles and maxillipeds, indicate poor ability for predation but point to an omnivorous detritus feeding mode. Poorly developed respiratory organs (small cylindrical epipods) suggest a relatively low level of locomotory activity. The field of vision may have been large and panoramic (stalked eyes). Rows of pores on 12 trunk segments are interpreted as possible sensory organs used for current detection. Females were brooding eggs (clusters of eggs preserved along anteroventral trunk). Microprobe analysis indicates that siderite is the major component of the nodules. Four events played a key‐role in the three‐dimensional preservation of syncarids: (1) rapid burial, (2) minimal decomposition, (3) phosphatic mineralization shortly after the animal's death and (4) nodule formation around the carcass. Palaeocaris secretanae is morphologically close to Recent syncarids such Anaspides tasmaniae (freshwater streams, Australia) in its general body plan and detailed anatomy, e.g. mouth parts, indicating morphological stasis in syncarids over more than 200 million years.     

Yanomami: The Fierce Controversy and What We Can Learn from It

Yanomami: The Fierce Controversy and What We Can Learn from It . Robert Borofsky. Berkeley: University of California Press, 2005. 372 pp.     

Do hermaphrodites of gynodioecious Phacelia linearis (Hydrophyllaceae) trade off seed production to attract pollinators?

Sexual selection theory predicts that hermaphroditic plants might trade off seed production to attract pollinators. This paper reports a test of this prediction in gynodioecious Phacelia linearis (Hydrophyllaceae), a species in which attractiveness to pollinators increases with corolla diameter. The relationship between corolla diameter and seed production was determined in three natural and three experimental populations. Phenotypic selection analysis was used, with lifetime seed production as a surrogate for fitness. Negative directional selection was expected on hermaphrodite corolla diameter. No directional selection (but possibly stabilizing selection) was expected on corolla diameter in females, which have smaller corollas than hermaphrodites. Shoot biomass and flowering time were included in selection analyses so that the effects of corolla size could be assessed independendy of these correlated characters. A parent-offspring study of the quantitative genetics of these characters also was performed. High seed production was associated with large shoot biomass (especially in natural populations) and early flowering (especially in experimental populations). The effect of hermaphrodite corolla size on seed production was not as predicted. Directional selection on hermaphrodite corolla diameter was generally positive. Directional selection on female corolla diameter was relatively weak and variable; stabilizing selection was found in one population. Most of the phenotypic selection on corolla diameter was caused by its (environmental) correlation with shoot biomass. Although these findings do not support the hypothesis that hermaphrodites trade off seed production to attract pollinators, a cautious interpretation is warranted. In one natural population, insect herbivory generated positive covariance between hermaphrodite corolla diameter and seed number, leading to a spurious estimate of positive directional selection for corolla diameter. Other, undetected sources of positive covariance between corolla size and seed production also might have obscured the expected tradeoff. Corolla diameter was found to be heritable, but shoot biomass and flowering time were not. The genetic correlation between hermaphrodite corolla diameter and female corolla diameter was positive and significant, but it was significantly less than 1, so corolla size could evolve independently in the two genders.