Walter E. Boles

An arid-adapted middle Pleistocene vertebrate fauna from south-central Australia

How well the ecology, zoogeography and evolution of modern biotas is understood depends substantially on knowledge of the Pleistocene. Australia has one of the most distinctive, but least understood, Pleistocene faunas. Records from the western half of the continent are especially rare. Here we report on a diverse and exceptionally well preserved middle Pleistocene vertebrate assemblage from caves beneath the arid, treeless Nullarbor plain of south-central Australia. Many taxa are represented by whole skeletons, which together serve as a template for identifying fragmentary, hitherto indeterminate, remains collected previously from Pleistocene sites across southern Australia. A remarkable eight of the 23 Nullarbor kangaroos are new, including two tree-kangaroos. The diverse herbivore assemblage implies substantially greater floristic diversity than that of the modern shrub steppe, but all other faunal and stable-isotope data indicate that the climate was very similar to today. Because the 21 Nullarbor species that did not survive the Pleistocene were well adapted to dry conditions, climate change (specifically, increased aridity) is unlikely to have been significant in their extinction.

Current status of species-level representation in faunas from selected fossil localities in the Riversleigh World Heritage Area, northwestern Queensland

Current lists of species-level representation in faunas from 80 Cenozoic fossil localities at the Riversleigh World Heritage Area have been compiled by review of recorded occurrences of taxa obtained from both published and unpublished sources. More than 290 species-level taxa are represented, comprising mammals, amphibians, reptiles, birds, fishes, molluscs and crustaceans. The data are presented for the purpose of ongoing palaeoecological and biochronological studies.

A new endemic family of New Zealand passerine birds: adding heat to a biodiversity hotspot

The results of phylogenetic analysis of two molecular datasets sampling all three endemic New Zealand ‘honeyeaters’ (Prosthemadera novaeseelandiae, Anthornis melanura and Notiomystis cincta) are reported. The undisputed relatedness of the first two species to other honeyeaters (Meliphagidae), and a close relationship between them, are demonstrated. However, our results confirm that Notiomystis is not a honeyeater, but is instead most closely related to the Callaeidae (New Zealand wattlebirds) represented by Philesturnus carunculatus in our study. An estimated divergence time for Notiomystis and Philesturnus of 33.8 mya (Oligocene) suggests a very long evolutionary history of this clade in New Zealand. As a taxonomic interpretation of these data we place Notiomystis in a new family of its own which takes the name Notiomystidae. We expect this new phylogenetic and taxonomic information to assist policy decisions for the conservation of this rare bird.

Out of Gondwana: the origin of passerine birds

Abstract Two recent papers analysing nuclear DNA sequence data shed new light on the origin of perching birds (Passeriformes) and the structure of their radiation. Both papers find that the New Zealand wrens Acanthisitta fall at the base of the passerine radiation, implying an origin of this clade in Gondwana. Additionally, among oscine passerines (songbirds), both papers fail to support a sister group relationship between the largely Australo–Papuan Corvida and the Afro–Eurasian Passerida, as outlined in Sibley and Ahlquists tapestry. Rather, they converge on a phylogeny in which the Passerida is nested within the Corvida, suggesting an origin of songbirds in eastern Gondwana (Australia plus New Guinea). Finally, a Cretaceous origin of passerine birds is supported by the new data, albeit more on grounds of biogeography than of molecular clocks. The new papers solidify a synthesis of paleontological, phylogenetic and molecular data that has been growing over the past decade, and pave the way for a new generation of comparative studies of passerines.

Unusual gut contents in a Cretaceous ichthyosaur.

Despite ichthyosaurs being one of the most extensively studied Mesozoic marine reptile groups, there is little documented direct evidence of dietary habits in most taxa. Here, we report the discovery of hatchling-sized marine protostegid turtle remains and an enantiornithine bird (in association with actinopterygian fish and phosphatic nodules) within the body cavity of a gravid female ichthyosaur (Platypterygius longmani) from the Lower Cretaceous of Australia; this is the first evidence, to our knowledge, of feeding by ichthyosaurs upon both turtles and birds. The exceptionally preserved gut contents show little evidence of digestion, suggesting consumption shortly before the ichthyosaurs death. Poor swimming ability may have made hatchling turtles easy prey that could have been either swallowed whole or processed by shake feeding. Ingestion of bird remains probably occurred through scavenging. Opportunistic feeding on vertebrates is at odds with existing interpretations of dietary habits in Cretaceous ichthyosaurs, which favour predation primarily upon cephalopods. Such specialization is considered a contributing factor in the groups ultimate extinction. However, the evidence here that at least some forms were able to use a wide range of available food types suggests that the decline of ichthyosaurs in the mid-Cretaceous may be linked to other factors such as competition with ecologically analogous pursuit predators.

Biogeographical and phylogenetic implications of an early Miocene wren (Aves: Passeriformes: Acanthisittidae) from New Zealand

ABSTRACT A new species and genus of acanthisittid wren (Aves: Passeriformes: Acanthisittidae) is described from the Early Miocene (19–16 Ma) St Bathans Fauna from Otago, New Zealand, based on four fossil bones. The first Tertiary fossil passerine to be described from New Zealand, it is similar in size to New Zealands smallest extant bird, the Rifleman Acanthisitta chloris. A phylogenetic analysis of 53 osteological characters and 24 terminal taxa, including four suboscines, basal corvoids (Menuridae, Atrichornithidae, Climacteridae, Ptilonorhynchidae, Maluridae, Dasyornithidae, Acanthizidae, Pardalotidae, Meliphagidae), and all seven Recent acanthisittid species, identifies it as the sister group to Acanthisitta. This, the first phylogenetic analysis of the basal passerine groups to use morphological characters, recovers a similar pattern of relationships of basal corvoid taxa to that obtained by recent molecular studies. The analysis also suggests that Acanthisitta chloris and the new species are the most deeply nested taxa within the family, suggesting that the radiation of Recent acanthisittids originated no later than the Early Miocene.

Molecular Phylogenetic Affinities of the Night Parrot (Geopsittacus occidentalis) and the Ground Parrot (Pezoporus wallicus)

ABssRAcr.-Although designating the Night Parrot (Geopsittacus occidentalis) and the Ground Parrot (Pezoporus wallicus) as each others closest taxonomic relatives is generally accepted, placing this group with respect to other Australo-Pacific parrots has proven problematical. To examine the phylogenetic relationships of these two species, a 924-bp fragment of the cytochrome-b gene was sequenced from single representatives of the following genera: Geopsittacus, Pezoporus, Neophema, Melopsittacus, Platycercus, Polytelis, Strigops, and Calyptorhynchus. Maximum-parsimony, maximum-likelihood, and distance trees all supported a close association between Geopsittacus and Pezoporus. These two genera were also found to be closely linked with Neophema and Melopsittacus. Despite superficial morphological similarities, Geopsittacus and Strigops (Kakapo) were found not to be closely related. Received 21 December 1992, accepted 6 October 1993.

Plumage patterns are good indicators of taxonomic diversity, but not of phylogenetic affinities, in Australian grasswrens Amytornis (Aves: Maluridae)

The grasswrens (Maluridae: Amytornis) are elusive songbirds from the arid zones of Australia. Although some other Australian bird genera are also largely restricted to arid regions, none show the level of localized taxonomic diversity seen in Amytornis. Furthermore, their cryptic plumage patterns provide excellent camouflage but make it difficult to determine whether shared patterns reflect phylogenetic relationships or adaptations to similar terrain. To resolve the systematics and patterns of ecological diversification within Amytornis, we here present the results of a phylogenetic analysis of mitochondrial and nuclear multi-locus data for all recognized species and most subspecies, using traditional concatenation-based methods as well as a coalescent-based species-tree approach. Phylogenetic patterns retrieved by the species-tree approach were highly congruent with traditional methods, although branch support was generally higher in concatenation-based analysis, suggesting that species-tree methods may furnish more conservative results. In terms of identifying taxonomic diversity there was good concordance between plumage-based assessments and DNA distances. The same concordance was not found when comparing plumage-based and DNA-based predictions of phylogenetic relationships. Four primary lineages were identified: (a) barbatus; (b) merrotsyi; (c) the textilis complex, purnelli, ballarae, goyderi and housei; and (d) woodwardi, dorotheae, and the striatus complex. There was no robust resolution of relationships between lineages. It appears that in Amytornis, plumage differentiation between discrete populations is taxonomically significant, and not greatly influenced by ecophenotypic variation. However, at the deeper phylogenetic level, similar suites of plumage characters may be phylogenetically uninformative because of homoplasy. The study reveals higher levels of taxonomic diversity in Amytornis than previously recognized, with many taxa being highly localized. Such extensive short range endemism is mainly encountered in poorly-dispersing invertebrates and is unique in Australian birds. The identification here of the additional restricted range taxa has important conservation implications.

Genyornis newtoni and Dromaius novaehollandiae at 30,000 b.p. in central northern New South Wales

Fossil remains of Genyornis newtoni and Dromaius novaehollandiae recovered from horizons at Cuddie Springs, in central northern New South Wales, are securely dated to greater than 30,000 b.p. Genyornis newtoni and D. novaehollandiae were found in sequential layers in association with artefacts of human occupation and other species of megafauna. Palaeoenvironmental information indicates the specimens of G. newtoni were deposited when the region supported an arid vegetation community, principally chenopod shrubland with scattered Eucalyptus and Acacia species. The appearance of Dromaius and disappearance of Genyornis coincided with a local shift to grasslands and the drying of the Cuddie Springs lake. New evidence is presented for the persistence of Genyornis in the arid zone during the lead up to the Last Glacial Maximum.

A new songbird (Aves: Passeriformes: Oriolidae) from the Miocene of Riversleigh, northwestern Queensland, Australia

A complete large mandible from the early Miocene Nevilles Garden Site, Riversleigh, northwestern Queensland, Australia, represents a new genus and species of songbird, Longimornis robustirostrata. L. robustirostrata is referred to the Oriolidae, closest to the figbirds Sphecotheres. It is the third named passerine from the Tertiary of Australia.