A new synthesis of the molecular systematics and biogeography of honeyeaters (Passeriformes: Meliphagidae) highlights biogeographical and ecological complexity of a spectacular avian radiation

Abstract

The passerine family Meliphagidae (the honeyeaters) comprises 175–180 species in 40–50 genera. It is an iconic element of the Australo‐Papuan avifauna and also occurs in Indonesia and on remote Pacific Ocean islands. Building on previous molecular studies that have pioneered a renewed understanding of the family's circumscription and systematics, we present an updated phylogenetic and systematics synthesis of honeyeaters derived from 112 mostly Australian, New Guinean and Wallacean species‐ and subspecies‐rank taxa aligned across 9246 positions spanning four mitochondrial and four nuclear genes. We affirm many of the recent changes advocated to the group's genus‐level systematics and offer some further refinements. The group's radiation appears to coincide broadly with the aridification of Australia in the Miocene, consistent with the time of origin of diversification of extant lineages in several other groups of Australian organisms. Most importantly, the complexity of the biogeography underlying the group's spectacular radiation, especially within Australia, is now apparent. Foremost among such examples is the robust evidence indicating that multiple, independent lineages of honeyeaters, including several monotypic genera, are endemic to the Australian arid zone, presumably having diverged and evolved within it. Also apparent and warranting further study are the phenotypic diversity among close relatives and the remarkably disjunct distributions within some clades, perhaps implying extinction of geographically intermediate lineages. Given such complexity, understanding the evolution of this radiation, which has thus far been intractable, relies on integration of molecular data with morphology, ecology and behaviour.

Spatial variation in avian bill size is associated with humidity in summer among Australian passerines

“…The species in our study ranged from 6 to 101 g (mean female body mass), included both insectivores and nectarivores and sedentary and mobile species, and occupied a diversity of climatic regions (Table 1) [22,23]. We measured the bills of 2,864 adult individuals using museum specimens collected across the geographic ranges of each species between 1970 and 2012 ( Table 1, Fig.…”

“…We then used these 2000 trees to calculate a majority-rule consensus phylogeny which was used as the basis for analysis. We resolved polytomies in the consensus phylogeny using a recently published phylogeny for the Meliphagidae [23]. We scaled the branch lengths observed in Meliphagidae [23] to that of the consensus phylogeny.…”

“…We resolved polytomies in the consensus phylogeny using a recently published phylogeny for the Meliphagidae [23]. We scaled the branch lengths observed in Meliphagidae [23] to that of the consensus phylogeny. The scaling was based on the distance from the base of the Meliphagidae to the species with the longest evolutionary branch length leading to it (Myzomela obscura).…”

“…Our study focused on 36 species of Australian passerine from the Meliphagoidea (honeyeaters and allies), a large and diverse group of Australasian passerines that is widely distributed across habitats and climatic regions and for which robust, species-level molecular phylogenies are available [22,23]. The species in our study ranged from 6 to 101 g (mean female body mass), included both insectivores and nectarivores and sedentary and mobile species, and occupied a diversity of climatic regions (Table 1) [22,23].…”

Placing the Fijian Honeyeaters within the meliphagid radiation: implications for origins and conservation

“…Cracraft and Feinstein 2000;Barker et al 2004;Driskell and Christidis 2004;Norman et al 2007;Nyári and Joseph 2011;Andersen et al 2014;Joseph et al 2014). The study of Andersen et al (2014) is of particular interest because it focuses on the origins of Pacific Island honeyeaters.…”