Phylogenetic Relationships in Pterodroma Petrels Are Obscured by Recent Secondary Contact and Hybridization

The classification of petrels (Pterodroma spp.) from Round Island, near Mauritius in the Indian Ocean, has confounded researchers since their discovery in 1948. In this study we investigate the relationships between Round Island petrels and their closest relatives using evidence from mitochondrial DNA sequence data and ectoparasites. Far from providing clear delimitation of species boundaries, our results reveal that hybridization among species on Round Island has led to genetic leakage between populations from different ocean basins. The most common species on the island, Pterodroma arminjoniana, appears to be hybridizing with two rarer species (P. heraldica and P. neglecta), subverting the reproductive isolation of all three and allowing gene flow. P. heraldica and P. neglecta breed sympatrically in the Pacific Ocean, where P. arminjoniana is absent, but no record of hybridization between these two exists and they remain phenotypically distinct. The breakdown of species boundaries in Round Island petrels followed environmental change (deforestation and changes in species composition due to hunting) within their overlapping ranges. Such multi-species interactions have implications not only for conservation, but also for our understanding of the processes of evolutionary diversification and speciation

A simple dynamic model explains the diversity of island birds worldwide

International audienc

The global and Western Indian Ocean dispersal of house geckos from Asia using historical and mitochondrial DNA perspectives

Seven species of house geckos occur across the scattered islands of the Indian Ocean. Two of these, Hemidactylus frenatus and H. parvimaculatus are both widespread and possess distribution profiles that suggest pre-European, or perhaps natural dispersal to some islands. Of these, only H. frenatus currently has sufficient molecular data to begin exploring dispersal patterns. This species is one of the most successful reptile colonists, as demonstrated by its global, pantropical distribution. While in some areas, such as Australia and continental South America, its dispersal patterns are both recent and well-known, early historical records of Hemidactylus in the Indian Ocean islands suggest earlier and/or potentially non-human-mediated dispersals. Here, we reviewed the historical literature and combined those reports with an assessment of mitochondrial DNA diversity of a global sampling of H. frenatus samples that included modern and museum specimens. Our results corroborate previous studies and demonstrate the relatively high diversity within this species’ native range in Southeast Asia. In addition, the phylogenetic analysis suggests both a potential cryptic species complex, as well as global geographic structuring of different H. frenatus mitochondrial lineages. This has important implications for many comparative studies of this complex. Frequent and ongoing dispersals and colonizations complicate the identification of potentially older migration patterns. Further assessments including additional samples and analyses of additional genetic markers are necessary to disentangle older from more recent dispersals within this intriguing species

The intercultural dodo: a drawing from the School of Bundi, Rājasthān

The iconic dodo Raphus cucullatus once occurred on the isolated Mascarene Island of Mauritius, situated in the southwestern Indian Ocean. Mauritius was once a paradise for a unique flora and fauna that evolved in isolation for 8 million years. The dodo was sought after by seafarers who visited the island from the early sixteenth century onwards because we know from remains surviving in collections and a series of artworks that captive dodos were transported to Europe, India and Japan. This article presents a hitherto unpublished image of a dodo, preserved in the collection of the Trustees, Chhatrapati Shivaji Maharaj Vastu Sangrahalaya, Mumbai, the formerly Prince of Wales Museum of Western India. The bird is situated in a non-Mauritian environment together with other animals and it is named in Hindi. We further explore the background of this creation and its implication on the iconography of the dodo