Studies of the selective advantages of divorce in socially monogamous bird species have unravelled extensive variation among different lineages with diverse ecologies. We quantified the reproductive correlates of mate retention, mate loss and divorce in a highly philopatric, colonially breeding biparental seabird, the Australasian gannet Morus serrator. Estimates of annual divorce rates varied between 40-43% for M. serrator and were high in comparison with both the closely related Morus bassanus and the range of divorce rates reported across monogamous avian breeding systems. Mate retention across seasons was related to consistently higher reproductive success compared with mate replacement, while divorce per se contributed significantly to lower reproductive output only in one of two breeding seasons. Prior reproductive success was not predictive of mate replacement overall or divorce in particular. These patterns are in accordance with the musical chairs hypothesis of adaptive divorce theory, which operates in systems characterised by asynchronous territorial establishment.

The forecast for the viability of populations depends upon metapopulation dynamics: the combination of reproduction and mortality within populations, as well as dispersal between populations. This study focuses on an Indo-Pacific bottlenose dolphin (Tursiops aduncus) population in coastal waters near Bunbury, Western Australia. Demographic modeling of this population suggested that recent reproductive output was not sufficient to offset mortality. Migrants from adjacent populations might make up this deficit, so that Bunbury would act as a "sink," or net recipient population. We investigated historical dispersal in and out of Bunbury, using microsatellites and mitochondrial DNA of 193 dolphins across five study locations along the southwestern Australian coastline. Our results indicated limited gene

The availability of molecular methods for avian sex identification has revolutionised the study of sexual differences in behaviour, morphology, life-history traits and conservation management. We implemented the recommendations of a recent review of DNA-based sex-identification by (1) verifying the sex-specificity and (2) estimating the accuracy of different sex-assignment methods in an apparently monomorphic seabird, the Australasian gannet (Morus serrator). The polymerase chain reaction (PCR) method based on the amplification of the sex-linked chromodomain-helicase-DNA binding gene (CHD) repeatedly assigned the same sex in 96% (n = 27 replicates) and correctly sexed all individuals with known gonadal anatomy (n = 6). PCR and sex-specific restriction fragment length polymorphism (RFLPs) showed agreement for 99.5% of individuals (n = 201). DNA-sexed pairs known to be social mates consisted of a male and a female in 96% of pairs sexed by PCR (n = 77) and 98% of pairs sexed by RFLP (n = 65). DNA-sexed females were in the bottom and males in the top copulatory position in 86% of observed copulations (n = 43 individuals). These results validate assumptions that both membership in social pairs and different copulatory positions can serve as reliable behavioural proxies for field-based sex identification in this colonial and obligately biparental seabird.

Thanatophilus micans and T. mutilatus have significance for forensic entomology. Their larvae are therefore described and a key is provided for identifying the larvae of Afrotropical Silphidae based on morphological characters. It is shown that seven common species of Thanatophilus can be distinguished by a 360 bp mtDNA sequence from the cytochrome oxidase I gene.

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