Paleontology Collected Works

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    The postcranial anatomy of two Middle Devonian lungfishes (Osteichthyes, Dipnoi) from Mt. Howitt, Victoria, Australia
    (Museum Victoria, 2009) Long, John A ; Clement, Alice M
    The postcranial skeletons of two upper Givetian lungfi shes from Mt. Howitt, Victoria, Australia, show remarkable similarities, despite the fact that one is a tooth-plated form (Howidipterus Long 1992) whilst the other has a denticulate dentition (Barwickia Long 1992). Both genera show identical body shape with a short fi rst dorsal fi n and greatly elongated second dorsal fi n, and small anal fi n. The cleithra and clavicles are remarkably similar except for Barwickia lacking external ornament on the lateral lamina of the cleithrum and having a smaller branchial lamina on the clavicle. Both have paddle-shaped subdermal anocleithra that meet the posterior process of the I bone, approximately the same numbers of cranial ribs, pleural ribs, supraneural and subhaemal spines, the same expanded dorsal and anal fi n basals with similar number of proximal and middle radials supporting the fi ns, and approximately the same number of radials supporting the hypochordal lobe of the caudal fi n. These numerous similarities in the postcranial skeletons of the two genera strongly suggest that their differing feeding mechanisms probably evolved from a shared ancestral form having a similar postcranial skeleton. Implications for hypotheses of dipnoan phylogeny are discussed. Keywords Pisces, osteichthyes, Dipnomorpha, Devonian, postcranial skeleton, anatomy, evolution, Australia
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    The phylogenetic origin of jaws in vertebrates: developmental plasticity and heterochrony
    (The Cleveland Museum of Natural History, 2010-11) Long, John A ; Hall, BK ; Mcnamara, KJ ; Smith, MM
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    A new species of Oligo-Miocene darter (Aves: Anhingidae) from Australia
    (Central Ornithology Publication Office, 2012) Worthy, Trevor
    A single fossil tarsometatarsus from the Etadunna Formation, of Late Oligocene–Early Miocene age, at the Snake Dam Locality in South Australia reveals the ï¬ rst pre-Pliocene record of anhingids in Australia. Anhinga walterbolesi sp. nov. provides the oldest record globally for the Anhingidae and, with the contemporary presence of stem-group phalacrocoracids in the same formation, indicates a probable Early Oligocene to Eocene age for the common ancestor of anhingids and phalacrocoracids.
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    High-Resolution Coproecology: Using Coprolites to Reconstruct the Habits and Habitats of New Zealand’s Extinct Upland Moa (Megalapteryx didinus)
    (Public Library of Science, 2012) Wood, Jamie ; Wilmshurst, Janet M ; Wagstaff, Steven J ; Worthy, Trevor ; Rawlence, Nicolas J ; Cooper, Alan
    Knowledge about the diet and ecology of extinct herbivores has important implications for understanding the evolution of plant defence structures, establishing the influences of herbivory on past plant community structure and composition, and identifying pollination and seed dispersal syndromes. The flightless ratite moa (Aves: Dinornithiformes) were New Zealand’s largest herbivores prior to their extinction soon after initial human settlement. Here we contribute to the knowledge of moa diet and ecology by reporting the results of a multidisciplinary study of 35 coprolites from a subalpine cave (Euphrates Cave) on the South Island of New Zealand. Ancient DNA analysis and radiocarbon dating revealed the coprolites were deposited by the extinct upland moa (Megalapteryx didinus), and span from at least 6,368631 until 694630 14C years BP; the approximate time of their extinction. Using pollen, plant macrofossil, and ancient DNA analyses, we identified at least 67 plant taxa from the coprolites, including the first evidence that moa fed on the nectar-rich flowers of New Zealand flax (Phormium) and tree fuchsia (Fuchsia excorticata). The plant assemblage from the coprolites reflects a highly-generalist feeding ecology for upland moa, including browsing and grazing across the full range of locally available habitats (spanning southern beech (Nothofagus) forest to tussock (Chionochloa) grassland). Intact seeds in the coprolites indicate that upland moa may have been important dispersal agents for several plant taxa. Plant taxa with putative anti-browse adaptations were also identified in the coprolites. Clusters of coprolites (based on pollen assemblages, moa haplotypes, and radiocarbon dates), probably reflect specimens deposited at the same time by individual birds, and reveal the necessity of suitably large sample sizes in coprolite studies to overcome potential biases in diet interpretation.
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    Fish remains, mostly otoliths, from the non-marine Early Miocene of Otago, New Zealand
    (Polskiej Akademii Nauk, Instytut Paleobiologii (Polish Academy of Sciences, Institue of Paleobiology), 2012) Schwarzhans, Werner ; Scofield, R Paul ; Tennyson, Alan J D ; Worthy, Jennifer P ; Worthy, Trevor
    Fish remains described from the early Miocene lacustrine Bannockburn Formation of Central Otago, New Zealand, con− sist of several thousand otoliths and one skeleton plus another disintegrated skull. One species, Mataichthys bictenatus Schwarzhans, Scofield, Tennyson, and T. Worthy gen. et sp. nov., an eleotrid, is established on a skeleton with otoliths in situ. The soft embedding rock and delicate, three−dimensionally preserved fish bones were studied by CT−scanning tech− nology rather than physical preparation, except where needed to extract the otolith. Fourteen species of fishes are de− scribed, 12 new to science and two in open nomenclature, representing the families Galaxiidae (Galaxias angustiventris, G. bobmcdowalli, G. brevicauda, G. papilionis, G. parvirostris, G. tabidus), Retropinnidae (Prototroctes modestus, P. vertex), and Eleotridae (Mataichthys bictenatus, M. procerus, M. rhinoceros, M. taurinus). These findings prove that most of the current endemic New Zealand/southern Australia freshwater fish fauna was firmly established in New Zea− land as early as 19–16 Ma ago. Most fish species indicate the presence of large fishes, in some cases larger than Recent species of related taxa, for instance in the eleotrid genus Mataichthys when compared to the extant Gobiomorphus. The finding of a few otoliths from marine fishes corroborates the age determination of the Bannockburn Formation as the Altonian stage of the New Zealand marine Tertiary stratigraphy.
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    Ancient DNA Analyses Reveal Contrasting Phylogeographic Patterns amongst Kiwi (Apteryx spp.) and a Recently Extinct Lineage of Spotted Kiwi
    (Public Library of Science, 2012) Shepherd, Lara D ; Worthy, Trevor ; Tennyson, Alan J D ; Scofield, R Paul ; Ramstad, Kristina M ; Lambert, David M
    The little spotted kiwi (Apteryx owenii) is a flightless ratite formerly found throughout New Zealand but now greatly reduced in distribution. Previous phylogeographic studies of the related brown kiwi (A. mantelli, A. rowi and A. australis), with which little spotted kiwi was once sympatric, revealed extremely high levels of genetic structuring, with mitochondrial DNA haplotypes often restricted to populations. We surveyed genetic variation throughout the present and pre-human range of little spotted kiwi by obtaining mitochondrial DNA sequences from contemporary and ancient samples. Little spotted kiwi and great spotted kiwi (A. haastii) formed a monophyletic clade sister to brown kiwi. Ancient samples of little spotted kiwi from the northern North Island, where it is now extinct, formed a lineage that was distinct from remaining little spotted kiwi and great spotted kiwi lineages, potentially indicating unrecognized taxonomic diversity. Overall, little spotted kiwi exhibited much lower levels of genetic diversity and structuring than brown kiwi, particularly through the South Island. Our results also indicate that little spotted kiwi (or at least hybrids involving this species) survived on the South Island mainland until more recently than previously thought.
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    A Megafauna’s Microfauna: Gastrointestinal Parasites of New Zealand’s Extinct Moa (Aves: Dinornithiformes)
    (Public Library of Science, 2013) Wood, Jamie ; Wilmshurst, Janet M ; Rawlence, Nicolas J ; Bonner, Karen I ; Worthy, Trevor ; Kinsella, John M ; Cooper, Alan
    We perform the first multidisciplinary study of parasites from an extinct megafaunal clade using coprolites from the New Zealand moa (Aves: Dinornithiformes). Ancient DNA and microscopic analyses of 84 coprolites deposited by four moa species (South Island giant moa, Dinornis robustus; little bush moa, Anomalopteryx didiformis; heavy-footed moa, Pachyornis elephantopus; and upland moa, Megalapteryx didinus) reveal an array of gastrointestinal parasites including coccidians (Cryptosporidium and members of the suborder Eimeriorina), nematodes (Heterakoidea, Trichostrongylidae, Trichinellidae) and a trematode (Echinostomida). Parasite eggs were most prevalent and diverse in coprolites from lowland sites, where multiple sympatric moa species occurred and host density was therefore probably higher. Morphological and phylogenetic evidence supports a possible vicariant Gondwanan origin for some of the moa parasites. The discovery of apparently hostspecific parasite taxa suggests paleoparasitological studies of megafauna coprolites may provide useful case-studies of coextinction.
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    Miocene fossils show that kiwi (Apteryx, Apterygidae) are probably not phyletic dwarves
    (Verlag Naturhistorisches Museum Wien, 2013) Worthy, Trevor ; Worthy, Jennifer P ; Tennyson, Alan J D ; Salisbury, Steven W ; Hand, Suzanne J ; Scofield, R Paul
    Until now, kiwi (Apteryx, Apterygidae) have had no pre-Quaternary fossil record to inform on the timing of their arrival in New Zealand or on their inter-ratite relationships. Here we describe two fossils in a new genus of apterygid from Early Miocene sediments at St Bathans, Central Otago, minimally dated to 19–16 Ma. The new fossils indicate a markedly smaller and possibly volant bird, supporting a possible overwater dispersal origin to New Zealand of kiwi independent of moa. If the common ancestor of this early Miocene apterygid species and extant kiwi was similarly small and volant, then the phyletic dwarfing hypothesis to explain relatively small body size of kiwi compared with other ratites is incorrect. Apteryx includes five extant species distributed on North, South, Stewart and the nearshore islands of New Zealand. They are nocturnal, flightless and comparatively large birds, 1–3 kg, with morphological attributes that reveal an affinity with ratites, but others, such as their long bill, that differ markedly from all extant members of that clade. Although kiwi were long considered most closely related to sympatric moa (Dinornithiformes), all recent analyses of molecular data support a closer affinity to Australian ratites (Casuariidae). Usually assumed to have a vicariant origin in New Zealand (ca 80–60 Ma), a casuariid sister group relationship for kiwi, wherein the common ancestor was volant, would more easily allow a more recent arrival via overwater dispersal.
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    First articulated phyllolepid placoderm from North America, with comments on phyllolepid systematics
    (The Academy of Natural Sciences of Philadelphia, 2013-03) Long, John A ; Daeschler, EB
    The first articulated phyllolepid placoderm from North America (outside of Greenland) is described from the Upper Devonian Catskill Formation in north-central Pennsylvania. Phyllolepis rossimontina Lane and Cuffey 2005, from the same formation, and the genus Phyllolepis are reviewed based on the new Catskill Formation material and data from a range of recently described Southern Hemisphere taxa. Phyllolepids can be a valuable tool for biostratigraphic correlation due to their narrow age range within the Famennian stage of the Late Devonian in the Euramerican Province (Northern Hemisphere). Faunal exchange between Euramerica and Gondwana during the Late Devonian and the association of Phyllolepis with early tetrapods are discussed in the context of early tetrapod biogeography.
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    Ancient DNA reveals elephant birds and kiwi are sister taxa and clarifies ratite bird evolution
    (American Association for the Advancement of Science, 2014-05-23) Mitchell, Kieren J ; Llamas, Bastien ; Soubrier, Julien ; Rawlence, Nicolas J ; Worthy, Trevor ; Wood, Jamie ; Lee, Michael S Y ; Cooper, Alan
    The evolution of the ratite birds has been widely attributed to vicariant speciation, driven by the Cretaceous breakup of the supercontinent Gondwana. The early isolation of Africa and Madagascar implies that the ostrich and extinct Madagascan elephant birds (Aepyornithidae) should be the oldest ratite lineages. We sequenced the mitochondrial genomes of two elephant birds and performed phylogenetic analyses, which revealed that these birds are the closest relatives of the New Zealand kiwi and are distant from the basal ratite lineage of ostriches. This unexpected result strongly contradicts continental vicariance and instead supports flighted dispersal in all major ratite lineages. We suggest that convergence toward gigantism and flightlessness was facilitated by early Tertiary expansion into the diurnal herbivory niche after the extinction of the dinosaurs.
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    Copulation in antiarch placoderms and the origin of gnathostome internal fertilisation
    (Nature Publishing Group, 2014-10-19) Long, John A ; Mark-Kurik, Elga ; Johanson, Zerina ; Lee, Michael S Y ; Young, Gavin C ; Min, Zhu ; Ahlberg, Per E ; Newman, Michael ; Jones, Roger ; den Blaauwen, Jan ; Choo, Brian ; Trinajstic, Kate
    Reproduction in jawed vertebrates (gnathostomes) involves either external or internal fertilization. It is commonly argued that internal fertilization can evolve from external, but not the reverse. Male copulatory claspers are present in certain placoderms, fossil jawed vertebrates retrieved as a paraphyletic segment of the gnathostome stem group in recent studies. This suggests that internal fertilization could be primitive for gnathostomes, but such a conclusion depends on demonstrating that copulation was not just a specialized feature of certain placoderm subgroups. The reproductive biology of antiarchs, consistently identified as the least crownward placoderms and thus of great interest in this context, has until now remained unknown. Here we show that certain antiarchs possessed dermal claspers in the males, while females bore paired dermal plates inferred to have facilitated copulation. These structures are not associated with pelvic fins. The clasper morphology resembles that of ptyctodonts, a more crownward placoderm group, suggesting that all placoderm claspers are homologous and that internal fertilization characterized all placoderms. This implies that external fertilization and spawning, which characterize most extant aquatic gnathostomes, must be derived from internal fertilization, even though this transformation has been thought implausible. Alternatively, the substantial morphological evidence for placoderm paraphyly must be rejected.
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    A Plains-wanderer (Pedionomidae) that did not wander plains: a new species from the Oligocene of South Australia
    (John Wiley & Sons, inc., 2014-11-03) De Pietri, Vanessa L ; Camens, Aaron ; Worthy, Trevor
    The remarkable fauna of Australia evolved in isolation from other landmasses for millions of years, yet understanding the evolutionary history of endemic avian lineages on the continent is confounded by the ability of birds to disperse over geographical barriers even after vicariance events. The Plains-wanderer Pedionomus torquatus (Charadriiformes) is an enigmatic, predominantly sedentary, quail-like bird that occurs exclusively in sparse native grasslands of south-eastern Australia. It is the only known species of its family (Pedionomidae), and its closest relatives are the South American seedsnipes (Thinocoridae). Here we describe a further representative of this lineage, Oligonomus milleri gen. et sp. nov. from the Late Oligocene of South Australia (26–24 Ma), which predates the earliest record of P. torquatus by ca. 22 Ma and attests to the presence of this lineage during Australia's period of isolation (50-15 Ma). Based on the morphology of the coracoid and the palynological record, we propose that O. milleri and P. torquatus were ecologically disparate taxa, and that similar to coeval marsupials, O. milleri inhabited well-wooded habitats, suggesting that the preference for grassland in the extant P. torquatus and thinocorids is likely convergent and not ancestral. The speciation event leading to the evolution of the extant Plains-wanderer was probably triggered by the spread of grasslands across Australia in the Late Miocene-Pliocene, which this record predates. The presence of a pedionomid in the Late Oligocene of Australia strengthens the hypothesis of a Gondwanan divergence of the lineages giving rise to Thinocoridae and Pedionomidae.
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    Miocene Fossils Reveal Ancient Roots for New Zealand’s Endemic Mystacina (Chiroptera) and Its Rainforest Habitat
    (Public Library of Science, 2015) Hand, Suzanne J ; Lee, Daphne E ; Worthy, Trevor ; Archer, Michael ; Worthy, Jennifer P ; Tennyson, Alan J D ; Salisbury, Steven W ; Scofield, R Paul ; Mildenhall, Dallas C ; Kennedy, Elizabeth M ; Lindqvist, Jon K
    The New Zealand endemic bat family Mystacinidae comprises just two Recent species referred to a single genus, Mystacina. The family was once more diverse and widespread, with an additional six extinct taxa recorded from Australia and New Zealand. Here, a new mystacinid is described from the early Miocene (19–16 Ma) St Bathans Fauna of Central Otago, South Island, New Zealand. It is the first pre-Pleistocene record of the modern genus and it extends the evolutionary history of Mystacina back at least 16 million years. Extant Mystacina species occupy old-growth rainforest and are semi-terrestrial with an exceptionally broad omnivorous diet. The majority of the plants inhabited, pollinated, dispersed or eaten by modern Mystacina were well-established in southern New Zealand in the early Miocene, based on the fossil record from sites at or near where the bat fossils are found. Similarly, many of the arthropod prey of living Mystacina are recorded as fossils in the same area. Although none of the Miocene plant and arthropod species is extant, most are closely related to modern taxa, demonstrating potentially long-standing ecological associations with Mystacina.
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    Avifauna from the Teouma Lapita Site, Efate Island, Vanuatu, Including a New Genus and Species of Megapode
    (University of Hawaii Press, 2015) Worthy, Trevor ; Hawkins, Stuart ; Bedford, Stuart ; Spriggs, Matthew
    The avifauna of the Teouma archaeological site on Efate in Vanuatu is described. It derives from the Lapita levels (3,000 – 2,800 ybp) and immedi-ately overlying middens extending to ∼2,500 ybp. A total of 30 bird species is represented in the 1,714 identiï¬ ed specimens. Twelve species are new records for the island, which, added to previous records, indicates that minimally 39 land birds exclusive of passerines were in the original avifauna. Three-fourths of the 12 newly recorded species appear to have become extinct by the end of Lapita times, 2,800 ybp. The avifauna is dominated by eight species of columbids (47.5% Minimum Number Individuals [MNI ]) including a large extinct tooth-billed pigeon, Didunculus placopedetes from Tonga, and a giant Ducula sp. cf. D. goliath from New Caledonia. Seabirds are rare despite the coastal location of the site. Fowl are important contributors to the Teouma avifauna, with the human-introduced Red Junglefowl Gallus gallus accounting for 15% MNI and present in all sampled layers. There are two species of megapodes (∼10% of MNI ), with the extant Vanuatu Megapode Megapodius layardi most abundant and represented at all levels in the deposits. A substantially larger extinct megapode, Mwalau walter-linii, n. gen., n. sp., is present only in the Lapita midden area, where it is rela-tively rare. This extinct species was larger than all extant megapodes but smaller than the extinct Progura gallinacea from Australia, with proportions most similar to those of Alectura, and was a volant bird. The remaining signiï¬ cant faunal component is rails, with four species present, of which Porphyrio melanotus was the most abundant. Rare but notable records include an undescribed large rail; a parrot, Eclectus sp. cf. E. infectus; a hornbill, Rhyticeros sp. cf. R. plicatus; and a coucal, Centropus sp. indet., all conservatively considered likely to be conspeciï¬ c with known taxa elsewhere in Melanesia.
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    First shark from the late Devonian (Frasnian) Gogo Formation, Western Australia sheds new light on the development of tessellated calcified cartilage
    (PLOS One, 2015-05-28) Long, John A ; Burrow, Carole J ; Ginter, Michal ; Maisey, John G ; Trinajstic, Kate ; Coates, Michael I ; Young, Gavin C ; Senden, Tim J
    Here we present new data from the first well-preserved chondrichthyan fossil from the early Late Devonian (ca. 380–384 Mya) Gogo Formation Lägerstatte of Western Australia. The specimen is the first Devonian shark body fossil to be acid-prepared, revealing the endoskeletal elements as three-dimensional undistorted units: Meckel’s cartilages, nasal, ceratohyal, basibranchial and possible epibranchial cartilages, plus left and right scapulocoracoids, as well as teeth and scales. This unique specimen is assigned to Gogoselachus lynnbeazleyae n. gen. n. sp.
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    Wading a lost southern connection: Miocene fossils from New Zealand reveal a new lineage of shorebirds (Charadriiformes) linking Gondwanan avifaunas
    (Taylor & Francis, 2015-10-13) De Pietri, Vanessa L ; Scofield, R Paul ; Tennyson, Alan J D ; Hand, Suzanne J ; Worthy, Trevor
    An endemic and previously unknown lineage of shorebirds (Charadriiformes: Scolopaci) is described from early Miocene (19 16 Ma) deposits of New Zealand. Hakawai melvillei gen. et sp. nov. represents the first pre-Quaternary record of the clade in New Zealand and offers the earliest evidence of Australasian breeding for any member of the Scolopaci. Hakawai melvillei was a representative of the clade that comprises the South American seedsnipes (Thinocoridae) and the Australian Plains-wanderer (Pedionomidae), and presumed derived features of its postcranial skeleton indicate a sister taxon relationship to Australian pedionomids. Our findings reinforce that terrestrial adaptations in seedsnipes and the Plains-wanderer are convergent as previously proposed, and support an ancestral wading ecology for the clade. Although vicariance events may have contributed to the split between pedionomids and H. melvillei, the proposed sister taxon relationship between these taxa indicates that the split of this lineage from
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    Early Gnathostome Phylogeny Revisited: Multiple Method Consensus
    (Public Library of Science, 2016) Qiao, Tuo ; King, Benedict ; Long, John A ; Ahlberg, Per E ; Zhu, Min
    A series of recent studies recovered consistent phylogenetic scenarios of jawed vertebrates, such as the paraphyly of placoderms with respect to crown gnathostomes, and antiarchs as the sister group of all other jawed vertebrates. However, some of the hylogenetic relationships within the group have remained controversial, such as the positions of Entelognathus, ptyctodontids, and the Guiyu-lineage that comprises Guiyu, Psarolepis and Achoania. The revision of the dataset in a recent study reveals a modified phylogenetic hypothesis, which shows that some of these phylogenetic conflicts were sourced from a few inadvertent miscodings. The interrelationships of early gnathostomes are addressed based on a combined new dataset with 103 taxa and 335 characters, which is the most comprehensive morphological dataset constructed to date. This dataset is investigated in a phylogenetic context using maximum parsimony (MP), Bayesian inference (BI) and maximum likelihood (ML) approaches in an attempt to explore the consensus and incongruence between the hypotheses of early gnathostome interrelationships recovered from different methods. Our findings consistently corroborate the paraphyly of placoderms, all `acanthodians' as a paraphyletic stem group of chondrichthyans, Entelognathus as a stem gnathostome, and the Guiyu-lineage as stem sarcopterygians. The incongruence using different methods is less significant than the consensus, and mainly relates to the positions of the placoderm Wuttagoonaspis, the stem chondrichthyan Ramirosuarezia, and the stem osteichthyan LophosteusÐthe taxa that are either poorly known or highly specialized in character complement. Given that the different performances of each phylogenetic approach, our study provides an empirical case that the multiple phylogenetic analyses of morphological data are mutually complementary rather than redundant.
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    Getting to the heart of a good fossil
    (eLife Sciences Publications, 2016) Long, John A
    The discovery of perfectly preserved 113-119 million year old fossilised hearts in a Brazilian fish Rhacolepis has significant implications for palaeontology and comparative anatomy.
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    Climate change not to blame for late Quaternary megafauna extinctions in Australia
    (Nature Publishing Group, 2016) Saltre, Frederik ; Rodriguez-Rey, M ; Brook, Barry W ; Johnson, Christopher N ; Turney, Chris S M ; Alroy, John ; Cooper, Alan ; Beeton, Nicholas ; Bird, Michael I ; Fordham, Damien A ; Gillespie, Richard ; Herrando-Perez, Salvador ; Jacobs, Zenobia ; Miller, Gifford H ; Nogues-Bravo, David ; Prideaux, Gavin John ; Roberts, Richard Graham ; Bradshaw, Corey J A
    Late Quaternary megafauna extinctions impoverished mammalian diversity worldwide. The causes of these extinctions in Australia are most controversial but essential to resolve, because this continent-wide event presaged similar losses that occurred thousands of years later on other continents. Here we apply a rigorous metadata analysis and new ensemble-hindcasting approach to 659 Australian megafauna fossil ages. When coupled with analysis of several high-resolution climate records, we show that megafaunal extinctions were broadly synchronous among genera and independent of climate aridity and variability in Australia over the last 120,000 years. Our results reject climate change as the primary driver of megafauna extinctions in the world’s most controversial context, and instead estimate that the megafauna disappeared Australia-wide ~13,500 years after human arrival, with shorter periods of coexistence in some regions. This is the first comprehensive approach to incorporate uncertainty in fossil ages, extinction timing and climatology, to quantify mechanisms of prehistorical extinctions.