A multilocus phylogeny of the world Sycoecinae fig wasps (Chalcidoidea: Pteromalidae).

The Sycoecinae is one of five chalcid subfamilies of fig wasps that are mostly dependent on Ficus inflorescences for reproduction. Here, we analysed two mitochondrial (COI, Cytb) and four nuclear genes (ITS2, EF-1α, RpL27a, mago nashi) from a worldwide sample of 56 sycoecine species. Various alignment and partitioning strategies were used to test the stability of major clades. All topologies estimated using maximum likelihood and Bayesian methods were similar and well resolved but did not support the existing classification. A high degree of morphological convergence was highlighted and several species appeared best described as species complexes. We therefore proposed a new classification for the subfamily. Our analyses revealed several cases of probable speciation on the same host trees (up to 8 closely related species on one single tree of F. sumatrana), which raises the question of how resource partitioning occurs to avoid competitive exclusion. Comparisons of our results with fig phylogenies showed that, despite sycoecines being internally ovipositing wasps host-switches are common incidents in their evolutionary history. Finally, by studying the evolutionary properties of the markers we used and profiling their phylogenetic informativeness, we predicted their utility for resolving phylogenetic relationships of Chalcidoidea at various taxonomic levels.

Determinants of quality in a long-lived colonial species.

1. In many animal populations a small proportion of individuals produce the majority of surviving offspring, but the underlying mechanisms are unclear. Behaviour may be an important determinant of variation in fitness: 'high-quality' individuals may have enhanced abilities in foraging or predator and parasite avoidance. 2. The role of behaviour in determining variation in quality was examined using the common guillemot Uria aalge, a monogamous seabird with biparental care. Using a novel mixed model approach, we analysed binary data on breeding success of each pair attempting to breed in each year with variables critical to breeding success (timing of breeding; inferred age; breeding experience and success; number of nest sites and partners) as fixed effects. Random effects for year, male, female and each distinct pairing of a male and a female were included in the model, allowing a quality estimate to be derived for each individual and pair. A range of behaviours associated with breeding were examined in relation to these quality estimates. 3. Breeding success declined with timing of breeding, and increased initially with age before declining in old age. It increased with previous successful experience, not breeding experience per se, until senescence effects became apparent. For males, breeding success declined with increasing numbers of mates. 4. The most important behavioural determinants of quality operated at the level of the pair, with the time mates spent together at the site and chick feeding rates both positively related to quality. At the individual level, trip durations and feeding rates were associated with female but not male quality, suggesting that pair quality was operating principally through the female. However, removal of laying date, the most important component in the binomial model, confirmed that the pair effect was much larger than the female effect. 5. This study demonstrates the potential of mixed modelling to determine quality estimates based on long-term breeding histories. The probability of a successful reproductive attempt was explained by the timing of breeding, age, successful breeding experience and number of mates. Behaviour was an important proximate mechanism underlying quality, in particular the foraging abilities of the pair, and the female's contribution to offspring provisioning. In species with biparental care, behavioural correlates of quality operate most strongly at the scale of the breeding pair, because contributions from both individuals are required for a successful outcome.