Birds in the diet of the Eurasian badger Meles meles: a review and meta-analysis

1. We reviewed 110 published studies of badger diet or badger predation of birds. The studies covered most of the Eurasian badger's range, from Ireland east to Japan and from Sweden south to southern Spain. 2. Bird remains were recorded in 2038 cases out of a total 36699 samples of badger faeces and stomachs. The overall percentage frequency of occurrence of bird remains in badger faeces and stomachs was 5.55% for all studies combined, and 7.97% for UK studies. The remains of 45 bird species from 11 orders were recorded. 3. The percentage frequency of occurrence of birds in badger diet increased significantly with latitude. There was no significant relationship between the occurrence of birds in badger diet and season. 4. While the prevalence of birds in the diet of badgers is generally low, the studies reviewed here provide insufficient evidence to assess whether badger predation has an impact on bird populations at a national scale, and experimental approaches to this problem are required.     

Cross‐species amplification at microsatellite loci in Australian quolls including the description of five new markers from the Chuditch (Dasyurus geoffroii)

The quolls are the largest native predators remaining on mainland Australia. We describe the cross‐species testing of all available microsatellite loci for representative across the entire distribution of quolls, with the additional characterization of five new microsatellite loci from the Chuditch. All primers produced clear and polymorphic amplification patterns containing between nine and 17 alleles and with high levels of diagnostic variability. These highly polymorphic primers make them useful additional tools in planning conservation strategies across related conspecifics, many of which are under threat.     

Rapid prey‐induced shift in body size in an isolated snake population (Notechis scutatus,Elapidae)

Abstract Geographic divergence in phenotypic traits between long‐isolated populations likely has a genetic basis, but can phenotypic plasticity generate such divergence rapidly in the initial stages of isolation? Australian tiger snakes (Notechis scutatus, Elapidae) provide a classic model system for the evolution of body size: mean adult sizes are relatively invariant in mainland populations, but many offshore islands have dwarf or giant populations. Previous work has shown a genetic basis to this divergence in long‐isolated islands (>10 000 years), but what of the initial stages of this process? Human translocation of mainland snakes to Carnac Island 90 years ago gives us a unique opportunity to assess the proximate reasons for the giant size of Carnac Island animals compared with mainland conspecifics. Our data suggest a major role for phenotypic plasticity. Feeding trials on captive snakes from both island and mainland populations showed a strong link between food intake and growth rates, similar in the two populations. Snakes given abundant food grew much larger than we have ever recorded in the wild, demonstrating that observed mean body sizes are driven by food availability rather than genetic limits to growth. In combination with earlier work showing genetic divergence in growth rates in snakes from long‐isolated islands, our data suggest that geographical divergence in mean adult body sizes in this system initially is driven by a rapid shift due to phenotypic plasticity, with the divergence later canalized by a gradual accumulation of genetic differentiation.     

Benefits of parental care: Do juvenile lizards obtain better‐quality habitat by remaining with their parents?

Abstract Evolutionary theory suggests that parental care is favoured by natural selection when the benefits to offspring fitness outweigh the costs of parental expenditure. The nature of such benefits may differ among species, however, especially in species reflecting independent evolutionary origins of parental care. Black rock skinks (Egernia saxatilis, Scincidae) of south‐eastern Australia are viviparous rock‐dwelling lizards with prolonged parent–offspring association; adult pairs vigorously defend their home range – and, when present, their offspring – against conspecifics. We addressed the hypothesis that, by remaining within their parents' (vigorously defended) home range, juveniles thereby obtain access to better‐quality habitats. Measurements of biologically significant variables (crevice size, sun exposure, vegetation cover) revealed little difference between shelter‐rocks used by solitary (‘orphan’) juveniles and those within family groups containing adults. Indeed, the only consistent differences involved larger (and therefore, less predator‐proof) crevices for juveniles within family groups than for solitary conspecifics. Our data thus falsify the hypothesis that parental care evolves because of benefits associated with habitat quality; instead, it appears that parental protection of juveniles against infanticidal conspecifics may be the most plausible benefit to parent–offspring association in this system.     

An unpublished letter by Richard Spruce on the theory of evolution

The unparalleled plant explorations of the British botanist Richard Spruce in the Amazon Valley and the northern Andes from 1849 to 1864 are now well known in scientific circles. What is not so widely recognized, however, is the depth of philosophy characteristic of this man, a depth of philosophy nurtured especially during his many years of living alone in closest association with nature in the forests of South America.     

CONDUCTING SENSORY RESEARCH WITH CHILDREN

Sensory testing with children can provide important insight into their likes and dislikes. Sensory professionals need to use methods that are appropriate for different age groups. This article reviews the current state of knowledge in this area and stresses the importance of considering the sensory, cognitive and social factors that may impact how best to conduct testing with children.     

Locomotion in Amphibian Larvae (or "Why Aren't Tadpoles Built Like Fishes?")

SYNOPSIS. A variety of morphological features that affect locomotiondistinguish larvae of the three living amphibian orders fromfishes and their larvae. The oddest amphibian larvae are anurantadpoles. With their globose bodies, concealed forelimbs, abruptlycompressed and terminally tapered tails, tadpoles not only differradically from fishes but they—unlike caecilians or salamanders—alsodiffer radically from their adults. Tadpoles typically haveless axial musculature and much simpler myotomes than fishes.Surprisingly, in terms of mechanical (propeller) efficiencyand maximum sprint speeds, tadpoles still perform as well asmany teleosts of comparable sizes. From a consideration of hydromechanics,no amphibian larvae appear to be designed for sustained swimmingat high speeds. High maneuverability, rather than sustainablespeed, are important for amphibian larval survival.Two key featuresof tadpoles are the absence of caudal vertebrae and unexposedpectoral appendages. With only a notochord to serve as a skeleton,the tadpole tail is extremely flexible. Because of this exceptionalflexibility, tadpoles can fold their tails up against the bodyand turn rapidly with virtually no displacement of their centerof mass. Caudal flexibility can be regulated by muscle activityin the tadpole to effect turning. Lateral appendages are notneeded for this movement and are free to develop directly intotheir adult morphology; the anterior ones develop under coverof an opercular fold where they do not contribute to drag. Acase is presented, based on the ecology of metamorphosis, thatanuran transformation should be as brief as possible. With nobone to resorb, metamorphosis of the anuran caudal appendagecan, indeed, be very rapid.The basic kinematics of constantvelocity straightforward swimming for tadpoles and salamanderlarvae is reviewed, as well as the kinematics and electromyographyof starting, stopping, and turning in tadpoles. An attempt ismade to relate swimming kinematics to the characteristic morphologiesof amphibian larvae. Swimming speed in Rana, Bufo and Aynbystomalarvae, which swim only intermittently, is modulated by changingtail beat frequency. However, Xenopus, which swims constantlyby sculling with its tail, regulates swimming speed (at lowto intermediate velocities) by varying the length of the propulsivewave in its tail. Xenopus and Rana differ in the morphologyof their notochord, spinal cord, spinal nerves, and spinal motorpool distribution within the spinal cord. These differencesmay underlie the different way these larvae regulate swimming.They may also reflect their phylogenetic history.     

Serologic Characteristics of Glucokinases from Entamoeba histolytica and Related Species1

SYNOPSIS. An enzyme inhibition technic was employed for quantitative comparison of the serologic properties of glucokinases from 4 groups of amebas which are structurally indistinguishable species: Entamoeba histolytica, E. moshkovskii, E. invadens and E. terrapinae. Antiglucokinase was prepared by immunizing rabbits with crude extracts of DKB and Laredo strains of E. histolytica. The combination of amebal glucokinase and homologous antibody was a pseudoirreversible reaction. The inhibition was proportional to the amount of antibody until at least 60% of the enzyme was inhibited, and the inhibition was 96–92% in the region of antibody excess. The nature of the inhibition was uncompetitive with respect to substrate. The presence of substrate had no effect upon the inhibition. Anti-DKB glucokinase inhibited equally glucokinases from DKB, JH, K9, 200, NRS, BH, JI, F22, and N strains. Anti-Laredo glucokinase equally inhibited glucokinases from Laredo, Huff, JA, AG, and 403 strains; 2.5–2.9 times as much antiserum was required to produce the same degree of inhibition between antisera and strains of heterologous group as with homologous antigen. Anti-DKB and anti-Laredo glucokinases cross-reacted with the enzyme from E. moshkovskii, but not with enzymes from reptilian amebas. A new glucokinase-anti-glucokinase dissociation test was developed which provides a method for qualitative differentiation of antiglucokinase against DKB strain from anti-glucokinase against Laredo strain.