Article
To read the full-text of this research, you can request a copy directly from the authors.

Abstract

The taxonomic status of some of New Zealand's endemic and threatened leiopelmatid frogs has been debated for decades. Clarifying this uncertainty is vital to their conservation, especially given the risk of extinction of cryptic taxa. We reexamined leiopelmatid diversity through multivariate analyses of the skeletal and external morphology of extinct and extant Leiopelma to determine morphological differentiation. Our results suggest that the morphological distinction between extinct taxa is greater than in modern extant taxa. While size ranges of postcranial elements overlapped within extant species, maxillae shape discriminated some extant taxa. We confirm the morphological distinctiveness of the extinct taxa recognized to date but identify latitudinal and altitudinal variation in postcra-nial element size and shape within the widespread Leiopelma markhami and L. waitomoensis, which suggest possible post-human extinction of cryptic taxa. Furthermore, the lack of morphological and osteological differentiation between L. archeyi and the insular extant L. hamiltoni and L. pakeka leads us to question the taxonomic distinctive-ness of these three taxa. Future genetic research using modern and ancient DNA is recommended to enable species limits within Leiopelma to be tested in more detail to provide an evidence-based assessment for their conservation management.

No full-text available

Request Full-text Paper PDF

To read the full-text of this research,
you can request a copy directly from the authors.

... femur (NMNZ S.46455, ∼1.7 mm) is within the range of L. hochstetteri (1.6-1.9 mm), L. hamiltoni (1.3-2.1 mm), and L. archeyi (1.1-1.8 mm) but is overall smaller than in L. markhami (1.7-3.5 mm), L. auroraensis (2.8 mm), L. waitomoensis (1.9-4.6 mm) and L. miocaenale (4.0 mm). All elements of L. bishopi n. sp. are smaller than the corresponding elements tentatively referred to the Miocene L. miocaenale and L. acricarina (see Worthy 1987a;Worthy et al. 2013;Easton et al. 2018). ...
... Relictual broadleaf forests and scrubland (see Wood 2007) would have become refugial habitats for many taxa, including the ancestors of the southernmost Leiopelma species L. auroraensis and L. markhami. Late Quaternary and modern distributions of Leiopelma species are restricted to regions associated with high rainfall (Bell et al. 1985;Easton et al. 2018). We hypothesise that aridification and opening up of the habitat during the Plio-Pleistocene led to a complete loss of habitat for Leiopelma in the eastern South Island. ...
Article
The fossil record of Leiopelma frogs in New Zealand is patchy, with remains previously reported only from the early Miocene (16–19 Mya) and late Quaternary (past 20 Ka). Here we describe Leiopelma bishopi n. sp. from the late Pliocene (3.7–2.4 Ma) of the eastern South Island. The subsequent extinction of frogs in this region is likely due to increased aridity following uplift of the Southern Alps and cooling associated with the Pleistocene Ice Ages. Discoveries from this unique Pliocene terrestrial fossil locality provide new and significant insights into how the dynamic climatic and geological history of Zealandia has shaped the evolution of its recent biota, especially for groups with a poor pre-Quaternary fossil record. LSID: urn:lsid:zoobank.org:pub:457F4C99-A561-4C3B-802C-3412EA3D7D42 Abbreviations: SVL: snout-vent length; NMNZ: Museum of New Zealand Te Papa Tongarewa, Wellington, New Zealand; WO: Waitomo Caves Museum, Waitomo, New Zealand
... Taken together, this study demonstrates insights into subsistence practices and extinction processes and demonstrates the value of genetic analyses of fossil assemblages. sexual dimorphism (20) or cryptic morphology (21). Furthermore, an important component of New Zealand's subfossil assemblages remains understudied, as nondiagnostic bones figure prominently in many deposits (22), especially in archaeological middens, where bones are typically fragmented by human processing. ...
... Similarly, the frogs within the genus Leiopelma were detected by two assays at four different paleontological sites. Although cryptic morphology renders species limits within leiopelmatids ambiguous (21), seven species are currently recognized, of which three are extinct. The introduction of the Pacific rat (Rattus exulans) to New Zealand, along with habitat loss, is thought to be the primary cause of population contractions and extinctions within Leiopelmatidae during the past 750 y (6), and today, leiopelmatids survive only on rat-free islands and in isolated areas of the North Island. ...
Article
Full-text available
Significance The mode and tempo of extinctions and extirpations after the first contact phase of human settlements is a widely debated topic. As the last major landmass to be settled by humans, New Zealand offers a unique lens through which to study interactions of people and biota. By analyzing ancient DNA from more than 5,000 nondiagnostic and fragmented bones from 38 subfossil assemblages, we describe species and patterns that have been missed by morphological approaches. We report the identification of five species of whale from an archaeological context in New Zealand and describe the prehistoric kākāpō population structure. Taken together, this study demonstrates insights into subsistence practices and extinction processes and demonstrates the value of genetic analyses of fossil assemblages.
... All native frogs in New Zealand belong to the endemic and evolutionarily basal genus, Leiopelma Fitzinger, 1861 (family: Leiopelmatidae) (Bell et al. 2004a(Bell et al. , 2004bRoelants et al. 2007;Bell and Pledger 2010;Bishop et al. 2013). After human settlement, several species of Leiopelma became extinct such as Leiopelma auroraensis Worthy, 1987, Leiopelma markhami Worthy, 1987, and Leiopelma waitomoensis Worthy, 1987, as well as other possible cryptic taxa (Easton 2018;Easton et al. 2018). Burns et al. (2018) recognised three extant species in the genus 1 : Leiopelma archeyi Turbott, 1942, Leiopelma hamiltoni McCulloch, 1919, and Leiopelma hochstetteri Fitzinger, 1861. ...
Article
Context Leiopelma archeyi is a threatened New Zealand amphibian species translocated for conservation purposes. A disease outbreak triggered the translocation of 70 frogs to Pureora Forest in 2006 to establish a new wild population of L. archeyi. Ten years after, 60 more frogs were translocated to this site to enhance the genetic and demographic profile of L. archeyi in Pureora Forest. Here, we analysed 14 years of capture–recapture monitoring data collected for this translocated population. Aims Our aim was to estimate population demographic parameters that allow us to assess the demographic performance of this translocated population. Methods We used spatially explicit capture–recapture (SECR; also called spatial capture–recapture) multi strata/session models to estimate population density and derive its rate of change over time. Key results Here we show that the density of translocated Leiopelma archeyi in Pureora (central North Island, New Zealand) remains stable for most of the study period. After the release of 70 frogs in 2006, density varied from 0.02 frogs/m2 in April 2007 to 0.06 frogs/m2 in December 2014. After the second release of 60 frogs in 2016, density in Pureora of L. archeyi varied from 0.21 frogs/m2 in November 2016 to 0.63 frogs/m2 in November 2018. Conclusions The study species is a long-lived k-selected species, therefore long-term monitoring (>20 years) is required to corroborate demographic indicators. Nevertheless, as the current density estimates are higher than the density estimated for this population after each release (April 2007 and November 2016), we suggest progress towards the establishment of a new wild population of L. archeyi in Pureora Forest. Implications Translocations are a useful conservation tool for many threatened species and post-release monitoring data are the main source of information needed to empirically prove their success.
... The top predators in the pre-human ecosystem were also birds including Haast's eagle (Aquila moorei) and Eyles' harrier (Circus eylesi; Tennyson and Martinson, 2007). Within reptiles, there were at least 110 species of Eugongylinae skinks and Diplodactylid geckos, seven Leiopelmatid frogs and one tuatara (Sphenodon punctatus) (Easton et al., 2017;Gemmell et al., 2020;Scarsbrook et al., 2021). ...
Article
Full-text available
The pre-human Aotearoa New Zealand fauna was dominated by avian and reptilian species. Prior to first human settlement by East Polynesian colonists, the top predators were two giant raptorial birds. Aside from humans themselves, colonisation also resulted in the simultaneous introduction of two novel mammalian predators into this naive ecosystem, the kiore (Pacific rat) and kurī (Polynesian dog). While the ecological impacts of kiore are relatively well understood, those of kurī are difficult to assess, and as such kurī have frequently been disregarded as having any meaningful impact on New Zealand’s biodiversity. Here we use the archaeological and palaeoecological record to reassess the potential impacts of kurī on this ecosystem. We argue that far from being confined to villages, kurī could have had a significant widespread but relatively localised impact on New Zealand’s avian, reptilian and marine mammal (seals and sea lions) fauna as a novel predator of medium-sized species. In this way, kurī potentially amplified the already significant impacts of Polynesian colonists and their descendants on New Zealand’s ecosystem, prior to European arrival. As such, kurī should be included in models of human impact in addition to over-hunting, environmental modification and predation by kiore.
... Currently, there are two remnant L. hamiltoni populations on predator-free Stephens Island (Takapourewa) and Maud Island (Te Pākeka) in the Marlborough Sounds. These populations, along with translocated populations on Motuara Island, Nukuwaiata Island, (Tocher and Pledger 2005;Tocher et al. 2006) and within Zealandia Ecosanctuary in Wellington (Lukis 2009;Karst 2013), represent the known entirety of the species (Worthy 1987;Bell and Bell 1994;Easton et al. 2018). Establishing populations of L. hamiltoni on the mainland of New Zealand is one of the primary goals of the New Zealand Frog Recovery Group for this species (Bishop et al. 2013), and information on the behavioural and social requirements of L. hamiltoni could assist in the design of appropriate translocation methodologies. ...
Article
Full-text available
Hamilton's frog (Leiopelma hamiltoni) is often found co-habiting retreat sites in the wild and in captivity, but whether co-habitation is a facet of sociality remains to be explored. We investigated the association patterns of retreat site sharing in four captive colonies of L. hamiltoni using a social networking framework. We tested whether the strength and heterogeneity of associations between individuals of each network varied from expected, or if frogs shared retreat sites randomly. We also investigated the temporal stability of pair-wise associations. In all tanks, we found that frogs shared retreat sites significantly more than would be expected if they displayed no degree of association. Further, we observed more preferred and avoided pairings than would be expected at random. Temporal stability between pairs of individuals within a tank were stable over short time periods (10-50 days) but decreased over time. High variation within and between tanks, however, prevented us from establishing a clear trend in temporal stability. Our results suggest that captive L. hamiltoni frogs, at least over the short-term, preferentially select retreat sites with specific individuals, and from this we infer that sociality in the form of retreat site sharing may form a key component of L. hamiltoni biology.
... duvaucelii'; perhaps detectable through fine-scale osteological analysis. Geometric morphometrics [36], a method of statistical shape analysis that enables improved detection and visualisation of subtle morphological differences (compared with traditional linear-based morphometrics [37,38]), has been widely applied in herpetofaunal studies; including the successful discrimination of closely-related species [39][40][41] and classification [42][43][44] of isolated cranial elements. We therefore predict osteological differences, if examined appropriately (using geometric morphometrics), will be sufficient for discriminating between extant diplodactylid genera (and potentially species), enabling the identification of isolated subfossil material, or reveal unidentified taxa that require description and diagnosis. ...
Article
Full-text available
New Zealand’s diplodactylid geckos exhibit high species-level diversity, largely independent of discernible osteological changes. Consequently, systematic affinities of isolated skeletal elements (fossils) are primarily determined by comparisons of size, particularly in the identification of Hoplodactylus duvaucelii, New Zealand’s largest extant gecko species. Here, three-dimensional geometric morphometrics of maxillae (a common fossilized element) was used to determine whether consistent shape and size differences exist between genera, and if cryptic extinctions have occurred in subfossil ‘Hoplodactylus cf. duvaucelii’. Sampling included 13 diplodactylid species from five genera, and 11 Holocene subfossil ‘H. cf. duvaucelii’ individuals. We found phylogenetic history was the most important predictor of maxilla morphology among extant diplodactylid genera. Size comparisons could only differentiate Hoplodactylus from other genera, with the remaining genera exhibiting variable degrees of overlap. Six subfossils were positively identified as H. duvaucelii, confirming their proposed Holocene distribution throughout New Zealand. Conversely, five subfossils showed no clear affinities with any modern diplodactylid genera, implying either increased morphological diversity in mainland ‘H. cf. duvaucelii’ or the presence of at least one extinct, large, broad-toed diplodactylid species.
... Hawaii (9), New Zealand (10)); whereas similar effects on herpetofaunal lineages remain poorly constrained (e.g. New Zealand (11,12)). ...
Preprint
Full-text available
Prehistoric anthropogenically-mediated extinctions have impacted global biodiversity; however effects on herpetofauna are poorly-documented. New Zealand’s Diplodactylidae geckos exhibit high species-level diversity, largely independent of discernible osteological changes (cryptic). Consequently, taxonomic affinities of isolated skeletal elements (fossils) are primarily determined by relative size, particularly in the identification of Hoplodactylus duvaucelii ; New Zealand’s largest extant gecko species. Here, three-dimensional geometric morphometrics of maxillae (a common fossilized element) was used to determine whether consistent shape and size differences exist between genera, and if cryptic extinctions have occurred in ‘Hoplodactylus cf. duvaucelii’ . Sampling included 13 Diplodactylidae species from five genera, and 11 Holocene ‘ H. cf. duvaucelii ’ subfossil individuals. We found phylogenetic history was the most important predictor of maxilla morphology among extant Diplodactylidae genera. Relative size comparisons could only differentiate Hoplodactylus from other genera, with the remaining genera exhibiting variable degrees of overlap. Six subfossils were positively identified as H. duvaucelii , confirming their proposed Holocene distribution throughout New Zealand. Conversely, five subfossils showed no affinities towards any modern Diplodactylidae genera, implying either increased morphological diversity in mainland ‘ H. cf. duvaucelii ’ or the presence of at least one extinct, large, broad-toed Diplodactylidae species. These results highlight the impact of anthropogenic disturbances on insular reptile diversity.
... It is one of the most isolated continental fragments (Zealandia; Mortimer et al., 2017) of the supercontinent Gondwana that was completely severed by ocean around 55 million years ago (Mya) (Roelants and Bossuyt, 2005). It has an excellent fossil record (Worthy and Holdaway, 2002;Worthy et al., 2017), and is home to extant taxa that are known from the old supercontinent (e.g., Giribet and Boyer, 2010;Easton et al., 2017;Wallis and Jorge, 2018). ...
Article
Full-text available
New Zealand's unique biodiversity is the product of at least 55 million years of geographic isolation, supplemented by persistent transoceanic migration. Palaeontological and genetic evidence suggest most New Zealand avifauna has colonized from Australia. We synthesize evolutionary genetic studies to show a previously unrecognized clustering of divergence times in Australian and New Zealand bird species pairs, across the avian phylogeny at the beginning of the Pleistocene, around 2.5 million years ago. The timing coincides with major climatic and vegetation changes with the initiation of the Plio-Pleistocene glacial cycles. Recent anthropogenic impacts and environmental modifications are replicating in some important ways Pleistocene glacial landscapes, resulting in a new wave of avian “native invaders” into New Zealand.
... Although it seems, from sporadic reports, that ship rats may represent the greatest mammalian predation threat to New Zealand's frogs , the current impacts of introduced predators on New Zealand frog populations are largely unknown (Baber, Moulton, Smuts-Kennedy, Gemmell, & Crossland, 2006;Bishop et al., 2013;Haigh, Pledger, & Holzapfel, 2007;Tocher & Pledger, 2005). The evidence to date is largely circumstantial: The extinction of three native frog species occurred synchronously with the arrival of introduced fauna (in association with human settlers), as did the range contraction of the currently extant species (Bell, 1994b;Easton et al., 2018;Towns & Daugherty, 1994;Worthy, 1987b). ...
Article
Full-text available
The decline of amphibians has been of international concern for more than two decades , and the global spread of introduced fauna is a major factor in this decline. Conservation management decisions to implement control of introduced fauna are often based on diet studies. One of the most common metrics to report in diet studies is Frequency of Occurrence (FO), but this can be difficult to interpret, as it does not include a temporal perspective. Here, we examine the potential for FO data derived from molecular diet analysis to inform invasive species management, using in-vasive ship rats (Rattus rattus) and endemic frogs (Leiopelma spp.) in New Zealand as a case study. Only two endemic frog species persist on the mainland. One of these, Leiopelma archeyi, is Critically Endangered (IUCN 2017) and ranked as the world's most evolutionarily distinct and globally endangered amphibian (EDGE, 2018). Ship rat stomach contents were collected by kill-trapping and subjected to three methods of diet analysis (one morphological and two DNA-based). A new primer pair was developed targeting all anuran species that exhibits good coverage, high taxonomic resolution, and reasonable specificity. Incorporating a temporal parameter allowed us to calculate the minimum number of ingestion events per rat per night, providing a more intuitive metric than the more commonly reported FO. We are not aware of other DNA-based diet studies that have incorporated a temporal parameter into FO data. The usefulness of such a metric will depend on the study system, in particular the feeding ecology of the predator. Ship rats are consuming both species of native frogs present on mainland New Zealand, and this study provides the first detections of remains of these species in mammalian stomach contents. K E Y W O R D S diet, Leiopelma, predation, primer, rat, trophic
Article
Full-text available
Since the 1980s, morphological and molecular research has resulted in significant advances in understanding the relationships and origins of the recent terrestrial vertebrate fauna in the New Zealand biogeographic region. This research has led to many taxonomic changes, with a significant increase in the number of bird and reptile species recognised. It has also resulted in the recognition of several more Holocene (<10 000 years ago) bird species extinctions. The conclusion that Holocene extinctions were primarily caused by human-hunting and predation by other introduced mammals (particularly rats and cats) has been supported by new data. Despite many local eradications of introduced pests, the number of introduced species has increased, with the establishment of five more foreign birds and (on Norfolk Island) the house gecko (Hemidactylus frenatus). Many new, significant New Zealand vertebrate fossils have been reported, including more dinosaurs from the Cretaceous, and the first Tertiary records of frogs, rhynchocephalids, lizards, crocodylians, bats and a terrestrial "Mesozoic ghost" mammal from the Early Miocene near St Bathans. For birds, the earliest known penguins in the world have been discovered, and there are intriguing Late Cretaceous - Early Paleocene remains still awaiting detailed description. Other significant Tertiary bird fossils reported include a rich avifauna from the Early Miocene St Bathans sites and a small terrestrial fauna from the Early Pleistocene near Marton. In line with the traditional theory, new research has supported the vicariant Gondwanan origin of some distinctive New Zealand terrestrial vertebrates, such as leiopelmatid frogs, tuatara and moa, and the immigration of many others, including New Zealand wattlebirds and piopio, during the Cenozoic. Extinctions caused by an asteroid impact and climate fluctuations probably explain the absence of many groups, such as crocodylians, dinosaurs, monotremes, palaelodids and swiftlets, from the modern fauna.
Article
Full-text available
AimWe used endemic frogs to test the hypothesis that New Zealand was fully submerged during the Oligocene marine transgression (c. 25-35 Ma, the Oligocene drowning) and that all the land biota subsequently arrived by dispersal - including the poorly dispersing frogs.LocationNew Zealand.Methods The complete mitochondrial genome of the New Zealand native frog Leiopelma hochstetteri was sequenced, assembled and analysed, and compared with that of L. archeyi.ResultsUsing many phylogenetic analyses we examined the evolutionary relationships of the two species of Leiopelma, both for the deepest divergence within New Zealand and relative to other frogs. Our results give estimates of well over 65 Ma for the first divergence of leiopelmatid frogs within New Zealand, and over 150 Ma for the divergence of Leiopelma from its closest relative, the North American tailed frog Ascaphus truei.Main conclusionsThe identification of such a deep divergence among the extant Leiopelma species provides some of the strongest support yet for a mixed-age model for the origin of New Zealand's terrestrial biota, where some elements are of vicariant origin and others have arisen by long-distance dispersal. This contradicts a full drowning model and supports the view that there must have been some continuous land through the Oligocene.
Article
Full-text available
Patterns of allozyme variation reveal that frogs from Maud Island, New Zealand, here designated Leiopelma pakeka, n. sp., are specifically distinct from L. hamiltoni from Stephens Island. Previously, the two populations had been thought to be conspecific. Leiopelma pakeka shows limited morphological differentiation from L. hamiltoni, but is highly distinct genetically. Among 12 allozyme loci resolved from toe tissue, the two taxa showed fixed differences at two loci and one significant frequency difference. L. hamiltoni was genetically more similar to L. archeyi (Nei's D = 0.18) than to L. pakeka (D = 0.24). The discovery that Maud Island and Stephens Island frogs are distinct species increases the conservation significance of both as the single known population of each species. L. hamiltoni is one of the world's rarest frogs and warrants the highest level of conservation protection.
Article
Full-text available
The jumping abilities of Bufo marinus, Bufo terrestris, Hyla crucifer and Rana clamitans were determined by averaging the distances jumped in two trials, each of five successive jumps. The smallest absolute and relative jumping abilities were possessed by Bufo, the greatest absolute jumping ability by Rana, and the greatest relative jumping ability by Hyla. Each frog jumped was skeletonized in order to test the correlation of jumping ability and osteological characteristics. Approximately 30 measurements taken of the postaxial and appendicular skeleton were converted into a series of proportions to reflect functional complexes. The proportions, in the main, possess low variability and, thus, high stability within each genus. By associating jumping abilities with proportions, several morphological and functional trends are disclosed. Notably, strong jumpers share a rectangular presacral platform, short forelimbs, large forefeet, short scapulae, long hindlimbs, and tibiofibula longer than femur.
Article
Full-text available
Over recent decades, investigators have studied many aspects of the natural history of the threatened and evolutionarily distinct Leiopelma frogs of New Zealand, effectively integrating natural history with conservation. To exemplify this, seven aspects of natural history (systematics, senses and defenses, threats, distribution and habitat, reproduction, demography, pathology) are related to 13 conservation needs, and the main linkages identified. This provides both a review of the frogs' natural history and an illustration of their conservation needs. Leiopelmatids have declined markedly and lost species, with three larger species (L. auroraensis, L. markhami, L. waitomoensis) now extinct, and four extant species (L. archeyi, L. hamiltoni, L. hochstetteri, L. pakeka) all threatened and on the amphibian EDGE list. Leiopelma archeyi tops that list. Potential threats include invasive mammalian predators and emerging diseases, particularly Amphibian Chytrid Fungus (Batrachochytrium dendrobatidis). Distribution surveys have clarified the frogs' current status, extending known ranges of some (i.e., L. archeyi, L. hochstetteri), and confirming restricted ranges of others (i.e., L. hamiltoni, L. pakeka). Observations on captive Leiopelma clarified patterns of reproduction and development, allowed assessment of evolutionary relationships, and are relevant to captive management of threatened populations. Long-term demographic studies represent some of the most lengthy population research on wild anurans, providing conservation-relevant data, e.g., revealing a decline in L. archeyi in the late 1990s, coinciding with finding chytridiomycosis in the species. While Leiopelma taxonomy needs more resolution, our knowledge of the natural history of these frogs has substantially informed conservation management, embracing programs dealing with habitat restoration, translocation, adaptive management, captive breeding, and disease prevention.
Data
Full-text available
Native frogs were formerly widespread and common throughout New Zealand. However, they are now much reduced in range, with remnant populations only occurring on the mainland of the North Island and on several islands in the Marlborough Sounds. The current agents of decline are thought primarily to be introduced mammalian predators, disease and habitat modification. The current recovery plan covers the period from 2013 to 2018 and sets in place the actions required to move into the next phase of recovery management for all four extant native frog species (Leiopelma spp.). In this respect, the plan spans a transitional phase to consolidate the security of the species and set the platform for their broader recovery.
Article
Full-text available
The first pre-Quaternary anurans from New Zealand are reported from the Early Miocene (19-16 Ma) St Bathans Fauna based on 10 fossil bones. Four bones representing two new species differing in size are described in Leiopelma: Leiopelmatidae, and are the first Tertiary records for the family. Six indeterminate frog fossils are morphologically similar to leiopelmatids and represent two species consistent in size with those known from diagnostic material. These records are highly significant, as minimally, they reduce the duration of the leiopelmatid ‘ghost lineage’ by c.20 million years and demonstrate that a diversity of leiopelmatids has long been present on New Zealand, supporting the ancient dichotomy of the extant species based on molecular data.
Article
Full-text available
Many ecological and evolutionary studies seek to explain patterns of shape variation and its covariation with other variables. Geometric morphometrics is often used for this purpose, where a set of shape variables are obtained from landmark coordinates following a Procrustes superimposition.We introduce geomorph: a software package for performing geometric morphometric shape analysis in the r statistical computing environment.Geomorph provides routines for all stages of landmark-based geometric morphometric analyses in two and three-dimensions. It is an open source package to read, manipulate, and digitize landmark data, generate shape variables via Procrustes analysis for points, curves and surfaces, perform statistical analyses of shape variation and covariation, and to provide graphical depictions of shapes and patterns of shape variation. An important contribution of geomorph is the ability to perform Procrustes superimposition on landmark points, as well as semilandmarks from curves and surfaces.A wide range of statistical methods germane to testing ecological and evolutionary hypotheses of shape variation are provided. These include standard multivariate methods such as principal components analysis, and approaches for multivariate regression and group comparison. Methods for more specialized analyses, such as for assessing shape allometry, comparing shape trajectories, examining morphological integration, and for assessing phylogenetic signal, are also included.Several functions are provided to graphically visualize results, including routines for examining variation in shape space, visualizing allometric trajectories, comparing specific shapes to one another and for plotting phylogenetic changes in morphospace.Finally, geomorph participates to make available advanced geometric morphometric analyses through the r statistical computing platform.
Article
Full-text available
Six species of Leiopelma frog endemic to New Zealand have been described, but three are extinct. Field surveys have extended the known contemporary ranges of L. archeyi and L. hochstetteri, though sub‐fossils reveal that both L. hochstetteri and L. archeyi/hamiltoni were formerly more widespread in New Zealand than they are now. A new North Island population of terrestrial Leiopelma resembling L. archeyi has recently been found. Introduced predators and food competitors, especially Rattus, have probably had a major detrimental impact on Leiopelma. No extant species is immediately at risk of extinction, but L. hamiltoni on Stephens and Maud Islands is very restricted in range and/or numbers.Leiopelma reaches high densities (up to 8 frogs/ m) in suitable rock‐strewn habitats and can be relatively long‐lived (L. archeyi 17+ years, L. hamiltoni 23+ years). Population levels of L. archeyi have fluctuated in a Coromandel study plot sampled approximately annually over 1982–93, but on Maud Island L. hamiltoni numbers were more stable or increased slightly over the years 1983–93. Experimental translocations of L. hamiltoni were made on Maud Island (1984–85) and on Stephens Island (1992). The new colony on Maud Island has bred successfully, and locally bred young have been recruited into the population.
Article
Full-text available
Hochstetter's frog, Leiopelma hoch‐stetteri, is now reduced to a series of isolated populations of variable size and extent. Although the species is not considered endangered, some of these isolates may be threatened or vulnerable. In a genetically and geographically discontinuous species like L. hochstetteri, every population may be an important component of total biogeographic diversity, since each isolate may represent an emergent historical entity. Variation in supernumerary chromosome number between populations and, particularly, the morphology of the sex chromosome, in conjunction with isozyme evidence, enable the identification of important subdivisions within L. hochstetteri. The population on Great Barrier Island is cytogenetically distinct since its members have no univalent, sex‐specific chromosome such as is present in all females from the North Island. Frogs from Mt Ranginui in the Rangitoto Range are the most chromosomally and biochemically distinctive of the North Island populations. Identification of geographic subdivisions in Hochstetter's frog indicates that conservation management practice should focus upon populations rather than the species as a whole.
Article
Full-text available
The extant New Zealand herpetofauna is now considered to consist of at least 65 endemic species of terrestrial reptiles and amphibians, an increase of about 64% in the size of the known fauna since 1980. The list includes four species of Leiopelma*, two species of Sphenodon, seven Naultinus, 22 Hoplodactyius, eight Cyclodina, and 22 Leiolopisma, all endemic to New Zealand. Discoveries in the past decade include many cryptic species identified using allozyme data, but also some morphologically well‐differentiated forms not previously known. At least 30 species (46%) are rare, threatened, or endangered, and 26 species (40%) are restricted largely or entirely to offshore islands. All but three species are protected. The New Zealand Department of Conservation has developed a comprehensive scheme for establishing management priority for indigenous species. At present, formal Recovery Plans exist in draft or approved form for at least 11 species, and more are in preparation.
Article
Full-text available
A terrestrial endemic frog resembling Leiopelma archeyi was discovered in the Whareorino Forest, northern King Country, New Zealand, in 1991, where it is broadly sympatric with L. hochstetteri. To clarify its taxonomic status, allozyme electrophoresis of toe tissue was used to compare it genetically with four other populations of terrestrial Leiopelma (L. archeyi from Tapu and Tokatea, Coromandel; L. hamiltoni from Stephens Island; L. pakeka from Maud Island). Thirteen presumed genetic (allozyme) loci could be consistently scored for the five populations. At 11 loci, no genetic differences were found between the Whareorino frog and the two Coromandel L. archeyi populations. Allelic frequencies differed slightly at two loci. We therefore conclude that the terrestrial Whareorino frog represents a western population of L. archeyi. L. hamiltoni from Stephens Island is genetically closer to L. archeyi than is L. pakeka from Maud Island. The Whareorino L. archeyi population is morphologically similar to Coromandel L. archeyi populations, although multivariate analysis suggests subtle morphological differences, including the relative position of the nostril. Size comparisons between Whareorino and three Coromandel sites (Moehau, Tapu, Tokatea) show there were more larger frogs (35–38 mm snout‐vent length) at Whareorino and Tokatea compared with Moehau and Tapu, where maximum snout‐vent lengths were 34 and 36 mm, respectively.
Article
Full-text available
Superimposition methods for comparing configurations of landmarks in two or more specimens are reviewed. These methods show differences in shape among specimens as residuals after rotation, translation, and scaling them so that they align as well as possible. A new method is presented that generalizes Siegel and Benson's (1982) resistant-fit theta-rho analysis so that more than two objects can be compared at the same time. Both least-squares and resistant-fit approaches are generalized to allow for affine transformations (uniform shape change). The methods are compared, using artificial data and data on 18 landmarks on the wings of 127 species of North American mosquitoes. Graphical techniques are also presented to help summarize the patterns of differences in shape among the objects being compared.
Article
Full-text available
New Zealand's endemic leiopelmatid frogs are all threatened with extinction. There is no obvious physical or behavioural difference between males and females of three of the four species and this lack of a sex identification technique is hindering conservation management. Twenty-one morphological features were measured for 67 live Leiopelma pakeka of known sex to determine whether a slight morphological difference existed that could be used for sex identification. Females were significantly longer in snout-to-vent length (SVL) than males, but as a great deal of overlap exists between sexes, this is not an ideal sex identification trait. No other physical characteristic was significantly different between sexes when adjusted for SVL. Discriminant analysis using a suite of traits was also unable to discriminate between sexes for frogs in the male–female overlap size range. The measurement of physical characteristics is inadequate for identifying sex in L.pakeka and other methods for sex identification must be developed. The reasons for the lack of sexual difference are unknown.
Article
Full-text available
New Zealand's native frogs (genus Leiopelma) are considered to be archaic amphibians of exceptional scientific interest that appear to have remained virtually unchanged for 160-200 million years. They are among the rarest extant amphibians and are highly restricted in distribution, confined to isolated, highly disjunct, populations on the North Island and a few small offshore islands in Cook Strait. Previous investigations have suggested, based on patterns of allozyme variation, that the Stephens Island frog (Leiopelma hamiltoni) and Archey's frog (L. archeyi) are sister taxa to the exclusion of the Maud Island frog, a species in close geographical proximity to the Stephens Island frog and previously viewed as a population of this species. As a consequence of these data, a new species, L. pakeka, the Maud Island Frog, has been described. This new species definition has dramatically enhanced the conservation status of L. hamiltoni, of which there are probably fewer than 150 individuals. In this study we re-examine the systematics of the Leiopelmatidae using mtDNA sequence analyses. Partial 12 S ribosomal RNA and cytochrome b (Cyt b) gene sequences were obtained for 57 frogs from six populations representing all four extant Leiopelma species. Contrary to previous reports we find L. pakeka and L. hamiltoni to be monophyletic. The amount of variation evident between these present species (<1% for Cyt b) is comparable to that seen between populations of L. archeyi. Based on these data, classification of L. pakeka and L. hamiltoni as separate species appears to be unwarranted, but they may be sufficiently distinct to warrant classification as evolutionarily significant units.
Article
Full-text available
All known Late Quaternary fossil avifaunas derived, at various times during the last century, from cave, swamp and dune deposits in Southland, South Island, New Zealand, are described Fifty eight native bird species are recorded from the deposits, notably including the fourth record of Dendroscansor decurvirostris The few leiopelmatid and sphenodontid bones are also listed Taphonomic biases limit comparison of faunal compositions across site‐types to moas However, the moa faunas reveal that quite different avifaunas lived in each of the dunes, alluvial swamplands and the well‐drained low hills, which probably reflects different vegetation communities in each Southland supported a mosaic of grassland, shrubland and tall, closed‐canopy podocarp forest during the Holocene Radiocarbon dates on bone gelatin are presented that indicate the fauna of Castle Rocks is of Late‐Holocene age, the fauna from Hamiltons Swamp at Winton is of mid‐Holocene age, and that from Kauana is >37 080 years old It is the oldest swamp fauna so far identified in New Zealand
Article
Full-text available
The late Quaternary fossil vertebrate faunas from 43 caves in Oligocene limestones and Ordovician marbles in the Takaka Valley and on Takaka Hill, northwest Nelson, New Zealand, are described and discussed. Depositional environments are described and interpreted. Major sites, including Ngarua Cave, Hawkes Cave, Kairuru Cave, Hobsons Tomo, and Irvines Tomo are described in detail. Many sites on Takaka Hill have been damaged by casual collectors since their discovery around 1900. Most sites were pitfall traps, but some deposits had been redistributed by water. Two deposits were attributed to an accumulation of material from pellets ejected by laughing owls (Sceloglaux albifacies), and of these the spectacularly rich Predator Cave site provided a large sample of small vertebrates.The fossil faunas included 42 species of land snails, three species of leiopelmatid frog, a tuatara, three species of geckoes, one or more species of skink, at least 58 (including two introduced) species of bird, three species of bats, two rats and the house mouse. Eighteen radiocarbon dates show that the faunas of the Hill and the Valley sites were laid down during the past 30,000 years. The dates ranged from 400 ± 62 to 29,011 ± 312 yrs bp. The date of 29,011 ± 312 yrs bp, recorded from a specimen in Hawkes Cave, supplants the date of 25,070 yrs bp from Te Ana Titi as the oldest cave specimen known in New Zealand. The introduced birds plus one rat and the mouse were in laughing owl middens, indicating that deposition by this species continued into the late 1800s or early 1900s.Two distinct faunal assemblages were present in both areas. These demonstrate that there were regional extinctions due to climatic and associated environmental changes at the end of the Otira (last) Glaciation. In contrast to the continental regions, where humans were already present 10,000 years ago, and where the causes of post‐glacial megafaunal extinctions are subject to intense debate, no species became extinct in New Zealand until about 1000 years ago when humans arrived. The fauna from the last (Otira) Glaciation and Late Glacial periods (30,000 to 10,000 yrs bp), contained taxa typical of similar‐aged deposits at Oparara and farther south on the West Coast, and of Holocene deposits in the east and south of the South Island. The faunas in deposits of Holocene age (< 10,000 yrs bp) contained taxa typical of local forests at the time of European contact, plus extinct taxa. Some taxa were common to faunas of both ages. The Otiran and Late Glacial fauna were characterised by the moas Pachyornis elephantopus, P. australis, Euryapteryx geranoides and Megalapteryx didinus, but Anomalopteryx didiformis was present only in Holocene deposits. Dinornis struthoides and D. novaezealandiae were present in deposits of both ages. The duck Euryanas finschi, eagle Harpagornis moorei, and Aptornis and takahe Porphyrio mantelli were also found only in Otiran ‐ Late Glacial ‐ age deposits.Petrels were very rare in the Takaka area. Some samples of Anas chlorotis and Cyanoramphus spp. were large enough for statistical analysis, and the ranges in individual size, measured by lengths of various longbones, are presented and discussed for the fossil populations. Remains of some anatids, including Hymenolaimus, were common in Takaka Hill deposits at considerable distances from surface water, suggesting that these waterfowl were then more terrestrial than since mammalian predators arrived. Bones of three further individuals of Dendroscansor decurvirostris found in Hobsons Tomo constitute the third record for this taxon.The Hill and the Valley faunas are compared and discussed, and the regional fauna as a whole is compared with those from Oparara, the West Coast, Poukawa Swamp, Waitomo, and the Far North dunelands. The fossil faunas of Takaka Hill demonstrate that there has been no interchange of North and South Island terrestrial vertebrates over the last 30,000 years, and they therefore suggest that there was no Cook Strait land bridge at any time during the Otira Glaciation.
Article
Full-text available
The late Quaternary fossil vertebrate faunas from 42 caves in Oligocene limestones of the Barrytown Syncline, Westland, New Zealand, are described and discussed. The Hermit's Cave deposit is probably derived from pellets ejected by laughing owls Sceloglaux albifacies at one of their roost sites. Radiocarbon dating shows that the faunas were laid down at various times during the past 25 000yr. A date of 25 070yr is the oldest so far obtained from any cave fossil in New Zealand. The fossil fauna consisted of 50 species of bird, tree frogs, one skink, one gecko, one tuatara, and two or possibly three bats. A glacial fauna, dating from the last (Otira) Glaciation and Late Glacial period, between 10 000-25 000 radiocarbon years ago, contained taxa typical of Holocene deposits in the east and south of the South Island. A Holocene fauna, deposited during the past 10 000yr, contained taxa typical of the West Coast forests at the time of European contact, plus extinct taxa. -from Authors
Article
Full-text available
The endemic New Zealand frog framily Leiopelmatidae has three living species, all with very restricted distributions, and three extinct species, whose former natural history is unknown. The subfossil distributions of the extant Leiopelma hochstetteri Fitzinger 1861, and L. hamiltoni McCulloch 1919, show that until the late Holocene these species ranged from Punakaiki, on the west coast of the South Island, to Waitomo in the North Island.The morphological characters of the frogs, and the characteristics of the subfossil sites, suggest that the presumably extinct L. waitomoensis Worthy 1987 was a strongly hopping, stream or streamside frog, whereas L. markhami Worthy 1987, a slightly smaller extinct species, was primarily a walking, terrestrial frog.The formerly widespread species of Leiopelma, (L. markhami, L. waitomoensis, L. hochstetterz, and L. hamiltom all tended to become larger in southern populations. Size appears to be negatively correlated with temperature.The distribution of body sizes among adults of the extant Maud Island population of L. hamiltoni is similar to that of the extinct population of the same species previously living at Karamea, northwest Nelson.The disappearance of the extinct species, and the decline in range of the surviving species, date to the last millenium and is probably correlated with the arrival of the kiore, Rattus exulans, in New Zealand.
Article
Full-text available
Three new species of leiopelmatid frog are described from New Zealand cave deposits. The osteology of the extant species L. hochstetteri, L. hamiltoni and L. archeyi is described in greater detail than previously. The data do not support the contention of Stephenson (1960), that L. archeyi is neotenic in relation to L. hamiltoni. Detailed osteological studies of the Leiopelmatidae support the distinction of that family from the Ascaphidae.-from Author
Article
Full-text available
Chromosomes exhibiting elevated levels of differentiation are termed hypervariable but no proposed mechanisms are sufficient to account for such enhanced evolutionary divergence. Both hypervariable sex and supernumerary (B) chromosomes were investigated in the endemic New Zealand frog, Leiopelma hochstetteri, which is chromosomally polymorphic both within and between populations and has sufficiently elevated variation that different populations can be identified solely by their C-banded karyotypes. This frog is further distinguished by the univalent, female-specific W-chromosome (0W/00 sex determination) uniquely possessed by North Island populations. This sex chromosome exhibited variation in morphology, size, and heterochromatin distribution, sufficient to resolve 11 different types, including isochromosomes. Five of the 12 populations examined also had supernumerary chromosomes that varied in number (up to 15 per individual) and morphology. Specific variations seen among the hypervariable chromosomes could have resulted from heterochromatinisation, chromosome fusions, loss-of-function mutations, deletions, and/or duplications. Frogs of the same species from Great Barrier Island, however, had neither supernumeraries nor the female-specific chromosome. The 0W/00 sex chromosome system must have been derived after the isolation of Great Barrier Island from North Island populations by raised sea levels between 14 000 and 8000 years ago. Furthermore, biochemical divergence between populations is minor and therefore the chromosomal variation seen is comparatively recent in origin. The one characteristic common to all known hypervariable chromosomes is curtailment or lack of recombination. Their accelerated evolution therefore is possible via the mechanism of Muller's ratchet, either alone or in concert with other factors.
Article
Full-text available
Leiopelma hochstetteri belongs to a singular anuran lineage endemic to New Zealand that diverged from other frogs about 200 million years ago. The species now is reduced to a series of isolated populations in the northern half of the North Island and Great Barrier Island. We have used mitochondrial and nuclear sequence data to examine the genetic affinities of extant populations of L. hochstetteri. Phylogenetic reconstructions reveal that populations are highly structured. Each of the geographically isolated populations harbours independent mtDNA lineages as well as different degrees of nuDNA differentiation. Moreover, molecular dating reveals that this structure originated in the early Pleistocene. This pattern of genetic structure likely results from unfavourable climatic conditions during the Pleistocene combined with the low dispersal ability of the species. Isolated populations in forested refugia existed even in the southern part of the distribution of the species during glacial cycles. Previously published variation in chromosome numbers and isozyme data are consistent with the new evidence. We identified 13 evolutionary significant units (ESUs) that should serve as the focus for future management and conservation of this species. KeywordsPhylogeography- Leiopelma -New Zealand-Conservation-Pleistocene
Article
Full-text available
The pristine island ecosystems of East Polynesia were among the last places on Earth settled by prehistoric people, and their colonization triggered a devastating transformation. Overhunting contributed to widespread faunal extinctions and the decline of marine megafauna, fires destroyed lowland forests, and the introduction of the omnivorous Pacific rat (Rattus exulans) led to a new wave of predation on the biota. East Polynesian islands preserve exceptionally detailed records of the initial prehistoric impacts on highly vulnerable ecosystems, but nearly all such studies are clouded by persistent controversies over the timing of initial human colonization, which has resulted in proposed settlement chronologies varying from approximately 200 B.C. to 1000 A.D. or younger. Such differences underpin radically divergent interpretations of human dispersal from West Polynesia and of ecological and social transformation in East Polynesia and ultimately obfuscate the timing and patterns of this process. Using New Zealand as an example, we provide a reliable approach for accurately dating initial human colonization on Pacific islands by radiocarbon dating the arrival of the Pacific rat. Radiocarbon dates on distinctive rat-gnawed seeds and rat bones show that the Pacific rat was introduced to both main islands of New Zealand approximately 1280 A.D., a millennium later than previously assumed. This matches with the earliest-dated archaeological sites, human-induced faunal extinctions, and deforestation, implying there was no long period of invisibility in either the archaeological or palaeoecological records.
Article
Full-text available
Multivariate Imputation by Chained Equations (MICE) is the name of software for imputing incomplete multivariate data by Fully Conditional Speci cation (FCS). MICE V1.0 appeared in the year 2000 as an S-PLUS library, and in 2001 as an R package. MICE V1.0 introduced predictor selection, passive imputation and automatic pooling. This article presents MICE V2.0, which extends the functionality of MICE V1.0 in several ways. In MICE V2.0, the analysis of imputed data is made completely general, whereas the range of models under which pooling works is substantially extended. MICE V2.0 adds new functionality for imputing multilevel data, automatic predictor selection, data handling, post-processing imputed values, specialized pooling and model selection. Imputation of categorical data is improved in order to bypass problems caused by perfect prediction. Special attention to transformations, sum scores, indices and interactions using passive imputation, and to the proper setup of the predictor matrix. MICE V2.0 is freely available from CRAN as an R package mice. This article provides a hands-on, stepwise approach to using mice for solving incomplete data problems in real data.
Article
Full-text available
The ratite moa (Aves: Dinornithiformes) were a speciose group of massive graviportal avian herbivores that dominated the New Zealand (NZ) ecosystem until their extinction approximately 600 years ago. The phylogeny and evolutionary history of this morphologically diverse order has remained controversial since their initial description in 1839. We synthesize mitochondrial phylogenetic information from 263 subfossil moa specimens from across NZ with morphological, ecological, and new geological data to create the first comprehensive phylogeny, taxonomy, and evolutionary timeframe for all of the species of an extinct order. We also present an important new geological/paleogeographical model of late Cenozoic NZ, which suggests that terrestrial biota on the North and South Island landmasses were isolated for most of the past 20-30 Ma. The data reveal that the patterns of genetic diversity within and between different moa clades reflect a complex history following a major marine transgression in the Oligocene, affected by marine barriers, tectonic activity, and glacial cycles. Surprisingly, the remarkable morphological radiation of moa appears to have occurred much more recently than previous early Miocene (ca. 15 Ma) estimates, and was coincident with the accelerated uplift of the Southern Alps just ca. 5-8.5 Ma. Together with recent fossil evidence, these data suggest that the recent evolutionary history of nearly all of the iconic NZ terrestrial biota occurred principally on just the South Island.
Article
Various nomenclatural errors in a recent revision of the frog family PELODRYADIDAE are corrected, including the necessary change of nomina for a subfamily and a genus.
Article
The allopatric model of biological speciation involves fracturing of a pre-existing species distribution and subsequent genetic divergence in isolation. Accumulating global evidence from the Pyrénées, Andes, Himalaya, and the Southern Alps in New Zealand shows the Pleistocene to be associated with the generation of new alpine lineages. By synthesising a large number of genetic analyses and incorporating tectonic, climatic, and population-genetic models, we show here how glaciation is the likely driver of speciation transverse to the Southern Alps. New calibrations for rates of molecular evolution and tectonic uplift both suggest a ∼2 million-year (Ma) time frame. Although glaciation is often seen as destructive for biodiversity, here we demonstrate its creativity, and suggest a general model for speciation on temperate mountain systems worldwide.
Article
Various nomenclatural errors in a recent revision of the frog family PELODRYADIDAE are corrected, including the necessary change of nomina for a subfamily and a genus.
Article
Leiopelma hamiltoni is a rare species known to occur on only Maud Island, where it is restricted to a 15 ha forest remnant, and Stephens Island, where it is confined to a 600 m2 rock-tumble. The frogs are terrestrial and nocturnal, and their activity is best accounted for by environmental factors relating to moisture: rainfall during or preceding searches and high relative humidity. However, within the generally cool and humid Maud Island forest, the activity of adult frogs was also positively correlated with atmospheric temperature. On both islands, but especially on Stephens, frogs spend the day mainly under rocks. On Stephens Island, dispersion of frog capture sites was highly clumped, concentrations of captures being made on Muehlenbeckia vines covering rocky areas with southerly aspect. There the population density of adult frogs was 58/100 m2. Frogs limit their activity on the surface to small areas which may overlap with those of other individuals. At Maud Island, juvenile frogs showed stronger site tenacity than adults. It is suggested that 0.5-1.0 ha of rocky habitat, preferably under forest, should suffice to sustain a population of L. hamiltoni and that, consequently, the Stephens Island habitat is too small to support long-term a viable population. As a conservation measure, proposal to create further rock habitat (or habitat providing retreat sites) in the vicinity of the Stephens Island habitat is supported. -from Author
Article
The known endemic frog fauna of New Zealand comprises 3 extant species of Leiopelma and undescribed extinct species from sub-fossil deposits. All extant species now have restricted distributions, especially L. hamiltoni, confined to two islands and L. archeyi, confined to the Coromandel area. They are protected by N.Z. legislation and no species is immediately endangered. Potential threats include fragmentation of habitat, the impact of introduced fauna and possibly reduced genetic variation in remnant populations. Conservation-oriented research and management programmes are outlined and the anti-predator mechanisms of Leiopelma reviewed. -Author
Article
Montane populations of green frogs are larger at all stages of development, and tadpoles take a year or two longer to complete metamorphosis than do lowland populations. Complementary field and laboratory studies demonstrated that the clinal variation in morphology and development is primarily induced by the environment. However, significant genetic differences in temperature optima, and temperature sensitivity of differentiation rates, growth rates, and stage-specific growth were demonstrated. The genetic differences were counter to the observed clinal variation, e.g., in cold temperature experiments designed to simulate mountain-top conditions, montane tadpoles actually developed faster and completed metamorphosis earlier and at a smaller size than did lowland tadpoles. A greater range of developmental variation than that observed is potentially inducible by the altitudinal gradient of temperatures. Natural selection has acted to minimize the inducible variation and has favored the shortest possible larval periods given the ambient temperature constraints. Only in this sense do montane and lowland green frogs show local adaptations to their respective environments. A new model of the interactions between the genotypic and induced phenotypic components of clinal variation is presented.
Article
It is widely recognised that the acquisition of high-resolution palaeoclimate records from southern mid-latitude sites is essential for establishing a coherent picture of inter-hemispheric climate change and for better understanding of the role of Antarctic climate dynamics in the global climate system. New Zealand is considered to be a sensitive monitor of climate change because it is one of a few sizeable landmasses in the Southern Hemisphere westerly circulation zone, a critical transition zone between subtropical and Antarctic influences. New Zealand has mountainous axial ranges that amplify the climate signals and, consequently, the environmental gradients are highly sensitive to subtle changes in atmospheric and oceanic conditions. Since 1995, INTIMATE has, through a series of international workshops, sought ways to improve procedures for establishing the precise ages of climate events, and to correlate them with high precision, for the last 30 000 calendar years. The NZ-INTIMATE project commenced in late 2003, and has involved virtually the entire New Zealand palaeoclimate community. Its aim is to develop an event stratigraphy for the New Zealand region over the past 30 000 years, and to reconcile these events against the established climatostratigraphy of the last glacial cycle which has largely been developed from Northern Hemisphere records (e.g. Last Glacial Maximum (LGM), Termination I, Younger Dryas). An initial outcome of NZ-INTIMATE has been the identification of a series of well-dated, high-resolution onshore and offshore proxy records from a variety of latitudes and elevations on a common calendar timescale from 30 000 cal. yr BP to the present day. High-resolution records for the last glacial coldest period (LGCP) (including the LGM sensu stricto) and last glacial-interglacial transition (LGIT) from Auckland maars, Kaipo and Otamangakau wetlands on eastern and central North Island, marine core MD97-2121 east of southern North Island, speleothems on northwest South Island, Okarito wetland on southwestern South Island, are presented. Discontinuous (fragmentary) records comprising compilations of glacial sequences, fluvial sequences, loess accumulation, and aeolian quartz accumulation in an andesitic terrain are described. Comparisons with ice-core records from Antarctica (EPICA Dome C) and Greenland (GISP2) are discussed. A major advantage immediately evident from these records apart from the speleothem record, is that they are linked precisely by one or more tephra layers. Based on these New Zealand terrestrial and marine records, a reasonably coherent, regionally applicable, sequence of climatically linked stratigraphic events over the past 30 000 cal. yr is emerging. Three major climate events are recognised: (1) LGCP beginning at ca. 28 000 cal. yr BP, ending at Termination I, ca. 18 000 cal. yr BP, and including a warmer and more variable phase between ca. 27 000 and 21 000 cal. yr BP, (2) LGIT between ca. 18 000 and 11 600 cal. yr BP, including a Lateglacial warm period from ca. 14 800 to 13 500 cal. yr BP and a Lateglacial climate reversal between ca. 13 500 and 11 600 cal. yr BP, and (3) Holocene interglacial conditions, with two phases of greatest warmth between ca. 11 600 and 10 800 cal. yr BP and from ca. 6 800 to 6 500 cal. yr BP. Some key boundaries coincide with tephras.
Article
Evidence from subfossils and from present distributions confirming range contractions and extinctions of New Zealand amphibians and reptiles is consistent with that from New Zealand landbirds, in which 40% of the fauna, including the largest species, has become extinct in the 1000 years since human arrival. The largest extant species of all higher taxa of herpetofauna—leiopelmatid frogs, tuatara, skinks, and geckos—are extinct on the mainland; 41 % of the extant fauna (27 of 65 species) survive largely or entirely on rat‐free offshore islands; and many species are now restricted to a few isolated locations, remnants of once wider distributions, a pattern called “secondary endem‐ism”. Habitat alterations and occasional human predation may have contributed to range contractions, but the primary factor in extinctions is almost certainly introduced mammals, especially rats. At least three lines of evidence support this view: (1) species diversities and population densities are both far higher on rat‐free islands than on mainland sites and rat‐inhabited islands; (2) nocturnal species have suffered far more than diurnal ones—all populations of tuatara, two of four* species of frogs, the largest Cyclodina skinks, and the largest species of Hoplodactylus geckos are now restricted to islands, most rat‐free; (3) lizard populations on islands from which rats have been exterminated have shown rapid increases in range of habitats occupied, densities attained, and in reproductive success.
Article
TAXONOMIC classification is a primary determinant of manage-ment priorities for endangered species. Neglect of distinct taxa may lead to their extinction, a problem exemplified by management of the New Zealand tuatara, Sphenodon, the only surviving genus of one order of reptiles. The pattern of genetic and morphological differentiation reported here supports a taxonomy dating from 1877 that identified two extant species, one subsequently separated into two subspecies. Tuatara were fully protected in 1895, but legislation and assessments of conservation status never acknow-ledged taxonomic differentiation, referring only to Sphenodon punctatus. Perceived monotypy of tuatara apparently forestalled management intervention on behalf of threatened populations, thus contributing to extinction of 10 of the 40 populations (25%) in the past century and the imminent extinction of four more. Iden-tification of diversity within tuatara warrants increased conserva-tion attention for the single populations of S. guntheri (here reinstated as a second living species) and the possibly extinct subspecies 5. p. reischeki.
Article
The possible significance of the developmental features of Leiopelma and Ascaphus is best considered in relationship to their systematic position amongst frogs. Nobls'e (1931) recognition of the primitiveness of these two genera has been upheld and confirmed by subsequent investigators. For example:— The above are some of the more important primitive characters of Leiopelma and Ascaphus and in many of them the two frogs show a close relationship to urodeles. Furthermore, many morphological characters previously considered to separate the Urodela from the Anura are now found not to apply to these primitive genera. Their anatomical relationships lend no support to the opinions advanced by Wintrebert (1922), Holmgren (1933, 1939), Säve-Söderbergh (1934, 1936) and Herre (1935) and recently upheld by Jarvik (1942) that Urodeles and Anurans have arisen independently of each other. For example, differences in the connections between the quadrate and the neurocranium in Urodela and in Anura seemed to demonstrate a gap which is now bridged by Ascaphus (Pusey, 1938, 1943) and by Leiopelma. The separation of the nasal capsules and the presence of an ethmoidal region of the cranial cavity in Leiopelma provides a condition intermediate between the two orders. The course of the hyoman-dibular nerve in Leiopelma displays relationships more comparable to those pertaining to Urodela than to Anura. But it is not only in many details of its adult anatomy that Leiopelma resembles urodeles; there are also striking resemblances in its development. The similarity is well shown by summarizing the developmental features and comparing them with those of urodeles laying large yolky eggs that undergo lengthy intracapsular development either in water or on land.
Article
Cook Strait, the central seaway through the axial ranges of New Zealand, has many inferred origins. A compilation of marine geological and geophysical datasets suggests that Cook Strait developed when five sedimentary basins at a rapidly changing, obliquely convergent, plate boundary were moved into line and were linked by strong tidal scour in middle Pleistocene times. The basins relate partly to oblique subduction north of Cook Strait and partly to intercontinental transform to the south. Prior to opening, muddy, subduction pull-down and foreland basins in the northwest were separated from equally quiet water, rotating, forearc to transform basins in the southeast. The land barrier between them narrowed and was finally breached as subduction-related basins migrated southwards and transform-related basins extended northwards in response to rotation and divergent branching of a major transcurrent fault.Following breaching, a history of alternating scour and quiet water deposition is recorded by a series of deep, irregular unconformities in muddy basin fill. Scour is correlated with interglacial periods of high sea level when land barriers were submerged and strong tides, caused by a 140° phase difference at either end of the strait, eroded muddy sediments deposited in glacial periods when an emergent landbridge limited tidal exchange.
Article
The Silences of the Archives, the Reknown of the Story. The Martin Guerre affair has been told many times since Jean de Coras and Guillaume Lesueur published their stories in 1561. It is in many ways a perfect intrigue with uncanny resemblance, persuasive deception and a surprizing end when the two Martin stood face to face, memory to memory, before captivated judges and a guilty feeling Bertrande de Rols. The historian wanted to go beyond the known story in order to discover the world of the heroes. This research led to disappointments and surprizes as documents were discovered concerning the environment of Artigat’s inhabitants and bearing directly on the main characters thanks to notarial contracts. Along the way, study of the works of Coras and Lesueur took a new direction. Coming back to the affair a quarter century later did not result in finding new documents (some are perhaps still buried in Spanish archives), but by going back over her tracks, the historian could only be struck by the silences of the archives that refuse to reveal their secrets and, at the same time, by the possible openings they suggest, by the intuition that almost invisible threads link here and there characters and events.
Article
The identification of species boundaries for allopatric populations is important for setting conservation priorities and can affect conservation management decisions. Tuatara (Sphenodon) are the only living members of the reptile order Sphenodontia and are restricted to islands around New Zealand that are free of introduced mammals. We present new data of microsatellite DNA diversity and substantially increased mtDNA sequence for all 26 sampled tuatara populations. We also re-evaluate existing allozyme data for those populations, and together use them to examine the taxonomic status of those populations. Although one could interpret the data to indicate different taxonomic designations, we conclude that, contrary to current taxonomy, Sphenodon is best described as a single species that contains distinctive and important geographic variants. We also examine amounts of genetic variation within populations and discuss the implications of these findings for the conservation management of this iconic taxon. Yes Yes
Article
It is widely recognised that the acquisition of high-resolution palaeoclimate records from southern mid-latitude sites is essential for establishing a coherent picture of inter-hemispheric climate change and for better understanding of the role of Antarctic climate dynamics in the global climate system. New Zealand is considered to be a sensitive monitor of climate change because it is one of a few sizeable landmasses in the Southern Hemisphere westerly circulation zone, a critical transition zone between subtropical and Antarctic influences. New Zealand has mountainous axial ranges that amplify the climate signals and, consequently, the environmental gradients are highly sensitive to subtle changes in atmospheric and oceanic conditions. Since 1995, INTIMATE has, through a series of international workshops, sought ways to improve procedures for establishing the precise ages of climate events, and to correlate them with high precision, for the last 30 000 calendar years. The NZ-INTIMATE project commenced in late 2003, and has involved virtually the entire New Zealand palaeoclimate community. Its aim is to develop an event stratigraphy for the New Zealand region over the past 30 000 years, and to reconcile these events against the established climatostratigraphy of the last glacial cycle which has largely been developed from Northern Hemisphere records (e.g. Last Glacial Maximum (LGM), Termination I, Younger Dryas). An initial outcome of NZ-INTIMATE has been the identification of a series of well-dated, high-resolution onshore and offshore proxy records from a variety of latitudes and elevations on a common calendar timescale from 30 000 cal. yr BP to the present day. High-resolution records for the last glacial coldest period (LGCP) (including the LGM sensu stricto) and last glacial-interglacial transition (LGIT) from Auckland maars, Kaipo and Otamangakau wetlands on eastern and central North Island, marine core MD97-2121 east of southern North Island, speleothems on northwest South Island, Okarito wetland on southwestern South Island, are presented. Discontinuous (fragmentary) records comprising compilations of glacial sequences, fluvial sequences, loess accumulation, and aeolian quartz accumulation in an andesitic terrain are described. Comparisons with ice-core records from Antarctica (EPICA Dome C) and Greenland (GISP2) are discussed. A major advantage immediately evident from these records apart from the speleothem record, is that they are linked precisely by one or more tephra layers. Based on these New Zealand terrestrial and marine records, a reasonably coherent, regionally applicable, sequence of climatically linked stratigraphic events over the past 30 000 cal. yr is emerging. Three major climate events are recognised: (1) LGCP beginning at ca. 28 000 cal. yr BP, ending at Termination I, ca. 18 000 cal. yr BP, and including a warmer and more variable phase between ca. 27 000 and 21 000 cal. yr BP, (2) LGIT between ca. 18 000 and 11 600 cal. yr BP, including a Lateglacial warm period from ca. 14 800 to 13 500 cal. yr BP and a Lateglacial climate reversal between ca. 13 500 and 11 600 cal. yr BP, and (3) Holocene interglacial conditions, with two phases of greatest warmth between ca. 11 600 and 10 800 cal. yr BP and from ca. 6 800 to 6 500 cal. yr BP. Some key boundaries coincide with tephras.
Article
Translocations are important tools in the field of conservation. Despite increased use over the last few decades, the appropriateness of translocations for amphibians and reptiles has been debated widely over the past 20 years. To provide a comprehensive evaluation of the suitability of amphibians and reptiles for translocation, we reviewed the results of amphibian and reptile translocation projects published between 1991 and 2006. The success rate of amphibian and reptile translocations reported over this period was twice that reported in an earlier review in 1991. Success and failure rates were independent of the taxonomic class (Amphibia or Reptilia) released. Reptile translocations driven by human-wildlife conflict mitigation had a higher failure rate than those motivated by conservation, and more recent projects of reptile translocations had unknown outcomes. The outcomes of amphibian translocations were significantly related to the number of animals released, with projects releasing over 1000 individuals being most successful. The most common reported causes of translocation failure were homing and migration of introduced individuals out of release sites and poor habitat. The increased success of amphibian and reptile translocations reviewed in this study compared with the 1991 review is encouraging for future conservation projects. Nevertheless, more preparation, monitoring, reporting of results, and experimental testing of techniques and reintroduction questions need to occur to improve translocations of amphibians and reptiles as a whole.
Article
Tuatara (two species of Sphenodon) are the last representatives of a branch of an ancient reptilian lineage, Sphenodontia, that have been isolated on the New Zealand landmass for 82 million years. We present analyses of geographic variation in allozymes, mitochondrial DNA, nuclear DNA sequences, and one-way albumin immunological comparisons. These all confirm a surprisingly low level of genetic diversity within Sphenodon for such an ancient lineage. We hypothesise a recent extended population bottleneck, probably during the Pliocene/Pleistocene glaciation cycles, to explain the current paucity of variation. All data sets reveal clear genetic differentiation between the northern populations and those in Cook Strait, but offer conflicting views of the history and taxonomic relationships of the Cook Strait population on North Brother Island, currently recognised as Sphenodon guntheri. Allozymes show this population to be the most divergent of all tuatara populations, but preliminary mitochondrial DNA data indicate few differences between S. guntheri and Cook Strait Sphenodon punctatus. Interpretation of the trees is confounded by the lack of a suitable outgroup. As in other cases of conflicting nuclear and mitochondrial data sets, the different data sets likely reveal different aspects of the animals' evolutionary history, and introgression is not uncommon between species pairs.