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A study designed to determine the independent effects of female mate choice and male-male competition on mating and reproduction in a group of captive Japanese macaques is described. The results, using endocrine, genetic and behavioural data, show that when potentially conflicting strategies are involved, female mate strategies can prevail over male-male competition when determining sexual and reproductive outcomes.

Abstract Backgound The RPS4 gene codifies for ribosomal protein S4, a very well-conserved protein present in all kingdoms. In primates, RPS4 is codified by two functional genes located on both sex chromosomes: the RPS4X and RPS4Y genes. In humans, RPS4Y is duplicated and the Y chromosome therefore carries a third functional paralog: RPS4Y2, which presents a testis-specific expression pattern. Results DNA sequence analysis of the intronic and cDNA regions of RPS4Y genes from species covering the entire primate phylogeny showed that the duplication event leading to the second Y-linked copy occurred after the divergence of New World monkeys, about 35 million years ago. Maximum likelihood analyses of the synonymous and non-synonymous substitutions revealed that positive selection was acting on RPS4Y2 gene in the human lineage, which represents the first evidence of positive selection on a ribosomal protein gene. Putative positive amino acid replacements affected the three domains of the protein: one of these changes is located in the KOW protein domain and affects the unique invariable position of this motif, and might thus have a dramatic effect on the protein function. Conclusion Here, we shed new light on the evolutionary history of RPS4Y gene family, especially on that of RPS4Y2. The results point that the RPS4Y1 gene might be maintained to compensate gene dosage between sexes, while RPS4Y2 might have acquired a new function, at least in the lineage leading to humans.

Abstract Background The popularity of microsatellites has greatly increased in the last decade on account of their many applications. However, little is currently understood about the factors that influence their genesis and distribution among and within species genomes. In this work, we analyzed carnivore microsatellite clones from GenBank to study their association with interspersed repeats and elucidate the role of the latter in microsatellite genesis and distribution. Results We constructed a comprehensive carnivore microsatellite database comprising 1236 clones from GenBank. Thirty-three species of 11 out of 12 carnivore families were represented, although two distantly related species, the domestic dog and cat, were clearly overrepresented. Of these clones, 330 contained tRNALys-derived SINEs and 357 contained other interspersed repeats. Our rough estimates of tRNA SINE copies per haploid genome were much higher than published ones. Our results also revealed a distinct juxtaposition of AG and A-rich repeats and tRNALys-derived SINEs suggesting their coevolution. Both microsatellites arose repeatedly in two regions of the insterspersed repeat. Moreover, microsatellites associated with tRNALys-derived SINEs showed the highest complexity and less potential instability. Conclusion Our results suggest that tRNALys-derived SINEs are a significant source for microsatellite generation in carnivores, especially for AG and A-rich repeat motifs. These observations indicate two modes of microsatellite generation: the expansion and variation of pre-existing tandem repeats and the conversion of sequences with high cryptic simplicity into a repeat array; mechanisms which are not specific to tRNALys-derived SINEs. Microsatellite and interspersed repeat coevolution could also explain different distribution of repeat types among and within species genomes. Finally, due to their higher complexity and lower potential informative content of microsatellites associated with tRNALys-derived SINEs, we recommend avoiding their use as genetic markers.

The copulation and masturbation events in wild habituated and nonhabituated troops of Japanese macaques on the protected island of Yakushima are described. The mating of a single male, indicating the presence of contaminant DNA that has previously mated with the same female and various other combinations for the DNA isolation are detected.

Backgound: The RPS4 gene codifies for ribosomal protein S4, a very well-conserved protein present in all kingdoms. In primates, RPS4 is codified by two functional genes located on both sex chromosomes: the RPS4X and RPS4Y genes. In humans, RPS4Y is duplicated and the Y chromosome therefore carries a third functional paralog: RPS4Y2, which presents a testis-specific expression pattern. Results: DNA sequence analysis of the intronic and cDNA regions of RPS4Y genes from species covering the entire primate phylogeny showed that the duplication event leading to the second Y-linked copy occurred after the divergence of New World monkeys, about 35 million years ago. Maximum likelihood analyses of the synonymous and non-synonymous substitutions revealed that positive selection was acting on RPS4Y2 gene in the human lineage, which represents the first evidence of positive selection on a ribosomal protein gene. Putative positive amino acid replacements affected the three domains of the protein: one of these changes is located in the KOW protein domain and affects the unique invariable position of this motif, and might thus have a dramatic effect on the protein function. Conclusion: Here, we shed new light on the evolutionary history of RPS4Y gene family, especially on that of RPS4Y2. The results point that the RPS4Y1 gene might be maintained to compensate gene dosage between sexes, while RPS4Y2 might have acquired a new function, at least in the lineage leading to humans. [ABSTRACT FROM AUTHOR]

Marmi, J., López-Giráldez, J. F.&Domingo-Roura, X. (2004). Phylogeny, evolutionary history and taxonomy of the Mustelidae based on sequences of the cytochromebgene and a complex repetitive flanking region.— Zoologica Scripta,33, 481–499.The Mustelidae is a diverse family of carnivores which includes weasels, polecats, mink, tayra, martens, otters, badgers and, according to some authors, skunks. Evolutionary relationships within the family are under debate at a number of different taxonomic levels, and incongruencies between molecular and morphological results are important. We analysed a total of 241 cytochromeb(cyt b) gene sequences and 33 sequences of a complex repetitive flanking region from 33 different species to compile an extensive molecular phylogeny for the Mustelidae. We analysed these sequences and constructed phylogenetic trees using Bayesian and neighbor-joining methods that are evaluated to propose changes to the taxonomy of the family. The peripheral position of skunks in phylogenetic trees based on both loci suggests that they should be considered a separate family, Mephitidae. The subfamily Melinae is the basal group within the Mustelidae and trees based on thecyt bgene suggest that the American badger,Taxidea taxus, should be considered a separate monotypic subfamily, Taxidiinae. Otters classified within the generaLutra,AmblonyxandAonyxare grouped within the same clade incyt band combined partialcyt band flanking region trees and show reduced levels of inter specific divergence, suggesting that they could be classified together under a single genus,Lutra. The Bayesian tree based on combined data from both loci supports the idea that subfamily Mustelinae is paraphyletic, as otters (subfamily Lutrinae) are included in this subfamily. Low levels of genetic divergence among European polecat,Mustela putorius, steppe polecat,Mustela eversmannii, and European mink,Mustela lutreola, suggest that these species could be considered subspecies within a single species,Mustela putorius. Our results are consistent with a rapid diversification of mustelid lineages in six different radiation episodes identified since the Early Eocene, the oldest events being the separation of subfamilies and the split of marten (Martes,Gulo) and weasel (Mustela) lineages in the Early Middle Miocene. The separation of New World from Old World lineages and the split of the remaining genera are estimated to have occurred in Late Miocene. The most recent events have been the differentiation of species within genera and this probably occurred in four radiation episodes at the end of Late Miocene, Early Pliocene, Late Pliocene and Pleistocene epochs. [ABSTRACT FROM AUTHOR]