A record of fossil shallow‐water whale falls from Italy

Twenty‐five Neogene–Quaternary whales hosted in Italian museum collections and their associated fauna were analysed for evidence of whale‐fall community development in shallow‐water settings. The degree of bone articulation, completeness of the skeleton and lithology of the embedding sediments were used to gather information on relative water depth, water energy, sedimentation rate and overall environmental predictability around the bones. Shark teeth and hard‐shelled invertebrates with a necrophagous diet in close association with the bones were used as evidence of scavenging. Fossil bone bioerosion, microbially mediated cementation and other mollusc shells in the proximity of the remains informed on past biological activity around the bones. The results are consistent with the hypothesis that shallow‐water whale falls differ from their deep‐water counterparts. Taphonomic pathways are more variable on the shelf and whale carcasses may not go through all steps of the ecological succession as recognised in the deep sea. Whilst the mobile scavenger and the enrichment opportunistic stages are well represented, chemosynthetic taxa typical of the sulphophilic stage were recovered only in one instance. The presence of a generalist fauna among the suspension feeding bivalves and carnivorous gastropods, and the extreme rarity of chemosynthetic taxa, suggest that predatory pressure rules out whale‐fall specialists from shallow shelf settings as in analogous cold seep and vent shallow‐water communities.     

Do ecologically close species shift their daily activities when in sympatry? A test on chamois in the presence of mouflon

Temporal partitioning of daily activities between species may promote coexistence within animal communities by reducing behavioural interference, particularly when species highly overlap in the use of space and resources. Such a strategy may be used by Alpine chamois (Rupicapra rupicapra rupicapra) when in the presence of mouflon (Ovis gmelini musimon × Ovis sp.), an introduced highly gregarious species with a broader ecological niche, overlapping with that of chamois. Using simultaneous monitoring of 29 Global Positioning System‐collared chamois and 12 mouflon, we assessed the temporal variation in activity patterns of chamois amongst two subpopulations: one without mouflon and one with mouflon, during January and August, which are the two most extreme periods of spatial overlap of mouflon with chamois distribution. Substantial differences in activity patterns between chamois and mouflon were observed (mean 13.8 ± 10.5% in January and 10.6 ± 11.6% in August). More subtle differences appeared between both subpopulations of chamois and persisted, regardless of the spatial overlap with mouflon (3.2 ± 1.8% in January and 2.6 ± 1.5% in August), thus highlighting that there is no behavioural interference from mouflon on chamois. Our findings suggest that the temporal partitioning of daily activities between chamois and mouflon, although probably a result of species‐specific adaptations to environmental conditions, may contribute to their coexistence. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 111 , 621–626.     

Applications of Population Genetics to Animal Breeding,from Wright,Fisher and Lush to Genomic Prediction

Although animal breeding was practiced long before the science of genetics and the relevant disciplines of population and quantitative genetics were known, breeding programs have mainly relied on simply selecting and mating the best individuals on their own or relatives’ performance. This is based on sound quantitative genetic principles, developed and expounded by Lush, who attributed much of his understanding to Wright, and formalized in Fisher’s infinitesimal model. Analysis at the level of individual loci and gene frequency distributions has had relatively little impact. Now with access to genomic data, a revolution in which molecular information is being used to enhance response with “genomic selection” is occurring. The predictions of breeding value still utilize multiple loci throughout the genome and, indeed, are largely compatible with additive and specifically infinitesimal model assumptions. I discuss some of the history and genetic issues as applied to the science of livestock improvement, which has had and continues to have major spin-offs into ideas and applications in other areas.THE success of breeders in effecting immense changes in domesticated animals and plants greatly influenced Darwin’s insight into the power of selection and implications to evolution by natural selection. Following the Mendelian rediscovery, attempts were soon made to accommodate within the particulate Mendelian framework the continuous nature of many traits and the observation by Galton (1889) of a linear regression of an individual’s height on that of a relative, with the slope dependent on degree of relationship. A polygenic Mendelian model was first proposed by Yule (1902) (see Provine 1971; Hill 1984). After input from Pearson, Yule again, and Weinberg (who developed the theory a long way but whose work was ignored), its first full exposition in modern terms was by Ronald A. Fisher (1918) (biography by Box 1978). His analysis of variance partitioned the genotypic variance into additive, dominance and epistatic components. Sewall Wright (biography by Provine 1986) had by then developed the path coefficient method and subsequently (Wright 1921) showed how to compute inbreeding and relationship coefficients and their consequent effects on genetic variation of additive traits. His approach to relationship in terms of the correlation of uniting gametes may be less intuitive at the individual locus level than Malécot’s (1948) subsequent treatment in terms of identity by descent, but it transfers directly to the correlation of relatives for quantitative traits with additive effects.From these basic findings, the science of animal breeding was largely developed and expounded by Jay L. Lush (1896–1982) (see also commentaries by Chapman 1987 and Ollivier 2008). He was from a farming family and became interested in genetics as an undergraduate at Kansas State. Although his master’s degree was in genetics, his subsequent Ph.D. at the University of Wisconsin was in animal reproductive physiology. Following 8 years working in animal breeding at the University of Texas he went to Iowa State College (now University) in Ames in 1930. Wright was Lush’s hero: ‘I wish to acknowledge especially my indebtedness to Sewall Wright for many published and unpublished ideas upon which I have drawn, and for his friendly counsel” (Lush 1945, in the preface to his book Animal Breeding Plans). Lush commuted in 1931 to the University of Chicago to audit Sewall Wright’s course in statistical genetics and consult him. Speaking at the Poultry Breeders Roundtable in 1969: he said, “Those were by far the most fruitful 10 weeks I ever had.” (Chapman 1987, quoting A. E. Freeman). Lush was also exposed to and assimilated the work and ideas of R. A. Fisher, who lectured at Iowa State through the summers of 1931 and 1936 at the behest of G. W. Snedecor.Here I review Lush’s contributions and then discuss how animal breeding theory and methods have subsequently evolved. They have been based mainly on statistical methodology, supported to some extent by experiment and population genetic theory. Recently, the development of genomic methods and their integration into classical breeding theory has opened up ways to greatly enhance rates of genetic improvement. Lush focused on livestock improvement and spin-off into other areas was coincidental; but he had contact with corn breeders in Ames and beyond and made contributions to evolutionary biology and human genetics mainly through his developments in theory (e.g., Falconer 1965; Robertson 1966; Lande 1976, 1979; see also Hill and Kirkpatrick 2010). I make no attempt to be comprehensive, not least in choice of citations.     

Predicting the ecological impacts of a new freshwater invader: functional responses and prey selectivity of the ‘killer shrimp’, Dikerogammarus villosus,compared to the native Gammarus pulex

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Effects of an invasive crayfish on the littoral macroinvertebrates of large boreal lakes are habitat specific

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Wildlife control,access and utilisation: Lessons from legislation,policy evolution and implementation in Zimbabwe

This paper retraces: (1) the promulgation of protectionist wildlife policies by colonial administrators at the turn of the 19th Century in Zimbabwe, and their evolutionary trajectory over distinct time periods, (2) the paradigmatic shift and the extent of evolution of wildlife policies with respect to the devolution thrust and local community participation to date. The aim is to re-ignite and keep alive the debate for the improvement of local community livelihoods by meeting their aspirations and addressing poverty. Another section explores the robustness of local community institutional framework following decades of research on their efficacy in the face of internal weaknesses and external pressures. This is discussed in the context of contested devolution and decentralisation concepts which not in the distant past became fashionable rhetoric in the field of local community empowerment in natural resource management. Areas of contests have been explored using a case study approach. Extensive literature consultation and gleaning of 127 published and relevant sources cutting across national, regional and global realms reveal that Zimbabwe and most southern African countries have evolved progressive policies. However, consistent with most literature, the implementation of these otherwise progressive policies remains problematic. Hence, the question, ‘when will community-based wildlife conservation initiatives like communal areas management programme for indigenous resources (CAMPFIRE) achieve their initially intended goals of devolution?’ remains largely unaddressed.     

Microbial biodiversity of the liquid fraction of rumen content from lactating cows

Host and dietary interactions with the rumen microbiome can affect the efficacy of supplements, and their effect on the composition of the bacterial population is still unknown. A 16S rRNA metagenomic approach and Next-Generation Sequencing (NGS) technology were used to investigate the bacterial microbiome composition in the liquid fraction of the rumen content collected via stomach tubing. To investigate biodiversity, samples were taken from three groups of four lactating dairy cows given a supplement of either 50 g of potato protein (Ctrl group), or 50 g of lyophilized Saccharomyces cerevisiae (LY group) or 50 g of dried S. cerevisiae (DY group) in a potato protein support. Rumen samples were collected after 15 days of dietary treatments and milk production was similar between the three groups. Taxonomic distribution analysis revealed a prevalence of the Firmicutes phylum in all cows (79.76%) and a significantly (P<0.05) higher presence of the genus Bacillus in the DY group. Volatile fatty-acid concentration was not significantly different between groups, possibly because of relatively high inter-animal variability or limited effect of the treatments or both, and the correlation analysis with bacterial taxa showed significant associations, in particular between many Firmicutes genera and butyrate. Limited differences were observed between dietary treatments, but the lack of microbiome data before yeast administration does not allow to draw firm conclusions on the effect of dietary treatments.