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Large-scale evaluations of genetic diversity in domestic livestock populations are necessary so that region-specific conservation measures can be implemented. We performed the first such survey in European sheep by analysing 820 individuals from 29 geographically and phenotypically diverse breeds and a closely related wild species at 23 microsatellite loci. In contrast to most other domestic species, we found evidence of widespread heterozygote deficit within breeds, even after removing loci with potentially high frequency of null alleles. This is most likely due to subdivision among flocks (Wahlund effect) and use of a small number of rams for breeding. Levels of heterozygosity were slightly higher in southern than in northern breeds, consistent with declining diversity with distance from the Near Eastern centre of domestication. Our results highlight the importance of isolation in terms of both geography and management in augmenting genetic differentiation through genetic drift, with isolated northern European breeds showing the greatest divergence and hence being obvious targets for conservation. Finally, using a Bayesian cluster analysis, we uncovered evidence of admixture between breeds, which has important implications for breed management.Heredity (2007) 99, 620–631; doi:10.1038/sj.hdy.6801039; published online 15 August 2007 [ABSTRACT FROM AUTHOR]

The relative importance of the factors driving change in the population dynamics of nematodes in the soil is almost completely unknown. Top-down control by micro-arthropod predators may have a significant impact on nematode population dynamics. We report experiments showing that mites and Collembola were capable of reducing nematode numbers in the laboratory and were feeding on a targeted nematode species in the field. A PCR-based approach was developed for the detection of predation on three species of slug- and insect-pathogenic nematodes: Phasmarhabditis hermaphrodita, Heterorhabditis megidis and Steinernema feltiae. The collembolan Folsomia candida and the mesostigmatid mite Stratiolaelaps miles were employed as model predators to calibrate post-ingestion prey DNA detection times. Fragments of cytochrome oxidase I (COI) mtDNA were sequenced and species-specific primers were designed, amplifying 154-, 154- and 203-bp fragments for each of the nematode species. Detection times for nematode DNA within the guts of Collembola were longer than in mites, with half-lives (50% of samples testing positive) of 08.75 h and 05.03 h, respectively. F. candida significantly reduced numbers of the nematode H. megidis, with rates of predation of ∼0.4 nematode infective juveniles per collembolan per hour over 10 h. Four taxa of field-caught micro-arthropod that had been exposed to the nematode P. hermaphrodita for a period of 12 h were analysed and significant numbers of three taxa tested positive. This is the first application of PCR techniques for the study of nematophagy and the first time these techniques have been used to measure predation on nematodes in the field. [ABSTRACT FROM AUTHOR]

We investigated the genetic structure within and among Bornean orang-utans (Pongo pygmaeus) in forest fragments of the Lower Kinabatangan flood plain in Sabah, Malaysia. DNA was extracted from hair and faecal samples for 200 wild individuals collected during boat surveys on the Kinabatangan River. Fourteen microsatellite loci were used to characterize patterns of genetic diversity. We found that genetic diversity was high in the set of samples (meanHE = 0.74) and that genetic differentiation was significant between the samples (averageFST = 0.04,P<0.001) withFST values ranging from low (0.01) to moderately large (0.12) values. PairwiseFST values were significantly higher across the Kinabatangan River than between samples from the same river side, thereby confirming the role of the river as a natural barrier to gene flow. The correlation between genetic and geographical distance was tested by means of a series of Mantel tests based on different measures of geographical distance. We used a Bayesian method to estimate immigration rates. The results indicate that migration is unlikely across the river but cannot be completely ruled out because of the limitedFST values. Assignment tests confirm the overall picture that gene flow is limited across the river. We found that migration between samples from the same side of the river had a high probability indicating that orang-utans used to move relatively freely between neighbouring areas. This strongly suggests that there is a need to maintain migration between isolated forest fragments. This could be done by restoring forest corridors alongside the river banks and between patches. [ABSTRACT FROM AUTHOR]

Twenty-nine human microsatellite primer pairs were screened for their utility in the cross-species amplification of baboon DNA derived from both blood and feces as part of a larger study to identify paternal half sisters in a population of wild baboons (Papio cynocephalus ). Forty-one percent (12/29) of the human primers successfully amplified baboon DNA. Of these 12 primers, six amplified fragments that were both polymorphic and heterozygous (mean number of alleles = 6, mean heterozygosity = 87%) and yielded repeatable results. However, only five of these six simple tandem repeat polymorphisms (STRPs) showed patterns of Mendelian inheritance (i.e., mothers and offspring shared at least one allele at each locus), and were therefore useful for determining relatedness between individuals. Analysis of the sixth primer revealed non-Mendelian inheritance, i.e., three of the six known mother-daughter pairs had no shared alleles. This failure was probably due to non-specific fragment amplification, and may have resulted from a different STRP locus being amplified in mother and daughter. This finding highlights the importance of sampling DNA from known parent-offspring pairs when screening microsatellite primers for genetic studies. Multiple, independent replications of genotypes and Mendelian checks are both particularly important when using cross-species amplification or when using a low-quality source of DNA. Am. J. Primatol. 51:219–227, 2000. © 2000 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

The article presents the abstract of the paper "Geographic Variation in the Taxonomy and Population Genetics of the Orang-utan Species in Borneo and Sumatra Islands," by B. Goossens and colleagues, that will be presented at the 21st Congress of the International Primatological Society in Entebbe, Uganda, from June 25-30, 2006.

The article presents the abstract of the paper "Cannabalism in Baboons: Sexual Selection Versus Hungry Hunters," by J. Altmann and colleagues, to be presented at the 21st Congress of the International Primatological Society in Entebbe, Uganda from June 25-30, 2006.

Abstract Background Previous phylogenetic analyses of African elephants have included limited numbers of forest elephant samples. A large-scale assessment of mitochondrial DNA diversity in forest elephant populations here reveals a more complex evolutionary history in African elephants as a whole than two-taxon models assume. Results We analysed hypervariable region 1 of the mitochondrial control region for 71 new central African forest elephants and the mitochondrial cytochrome b gene from 28 new samples and compare these sequences to other African elephant data. We find that central African forest elephant populations fall into at least two lineages and that west African elephants (both forest and savannah) share their mitochondrial history almost exclusively with central African forest elephants. We also find that central African forest populations show lower genetic diversity than those in savannahs, and infer a recent population expansion. Conclusion Our data do not support the separation of African elephants into two evolutionary lineages. The demographic history of African elephants seems more complex, with a combination of multiple refugial mitochondrial lineages and recurrent hybridization among them rendering a simple forest/savannah elephant split inapplicable to modern African elephant populations.

Patterns of genetic structure in eusocial naked mole-rat populationswere quantified within and among geographically distant populations using multilocus DNA fingerprinting and mitochondrial DNA (mtDNA) sequence analysis. Individuals within colonies were genetically almost monomorphic, sharing the same mtDNA control region haplotype and having coefficients of band sharing estimated from DNA fingerprints ranging from 0.93 to 0.99. Family analysis of a hybrid captive colony of naked mole-rats with increased levels of genetic variability using multilocus DNA fingerprinting gave results consistent with Mendelian inheritance, and has revealed for the first time that multiple paternity can occur. In a survey of wild colonies from Ethiopia, Somalia and locations in northern and southern Kenya, we have examined mtDNA control region sequence variation in 42 individuals from 15 colonies, and together with multilocus DNA fingerprinting and mtDNA cytochrome-b sequence analysis in selected individuals have shown that these populations show considerable genetic divergence. Most of the variance in sequence divergence was found to be between geographical locations (Phict = 0.68) and there was a significant correlation between sequence divergence and geographical separation of haplotypes. Six colonies from Mtito Andei in southern Kenya shared the same control region haplotype, suggesting a recent common maternal ancestor. In contrast, out of four colonies at Lerata in north Kenya, three haplotypes were identified, and phylogenetic analysis suggests that this area may be a zone where two distinct lineages are in close proximity. Genetic distances were maximal between Ethiopian and southern Kenyan populations at 5.8% for cytochrome-b, and are approaching interspecific values seen between other Bathyergids. [ABSTRACT FROM AUTHOR]