Graham P Wallis

Graham P Wallis
University of Otago · Department of Zoology

PhD

About

243
Publications
34,500
Reads
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5,848
Citations
Introduction
We are currently investigating the evolution and expression of an adaptively-evolving zona pellucida-domain gene in galaxiid fishes (MBE 28:399-406).
Additional affiliations
May 2011 - June 2011
Naturalis Biodiversity Center
Position
  • Temminck Fellow
May 2008 - July 2008
National Museum of Natural History
Position
  • Temminck Fellow
May 1988 - present
The University of Otago
Position
  • Evolutionary genetics of NZ fishes and insects
Education
September 1977 - September 1981
University of Wales, Swansea
Field of study
  • Biochemical genetics of gobies
September 1974 - June 1977
University of Wales, Swansea
Field of study
  • Genetics

Publications

Publications (243)
Article
Full-text available
Hybridization between divergent lineages often results in reduced hybrid viability. Here we report findings from a series of independent molecular analyses over several seasons on four life stages of F1 hybrids between the newts Triturus cristatus and T. marmoratus. These two species form a bimodal hybrid zone of broad overlap in France, with F1 hy...
Article
New Zealand has long been a conundrum to biogeographers, possessing as it does geophysical and biotic features characteristic of both an island and a continent. This schism is reflected in provocative debate among dispersalist, vicariance biogeographic and panbiogeographic schools. A strong history in biogeography has spawned many hypotheses, which...
Article
Full-text available
We describe the intron–exon structure and DNA/protein sequences of a new larval glycoprotein (LGP) gene from nine species of galaxiid fish. The gene has a distant similarity to Danio THP (Tamm–Horsfall urinary glycoprotein; uromodulin) and cichlid SPP120 (seminal plasma glycoprotein) due to conserved features of its zona pellucida (ZP) domain, incl...
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 synthesis...
Article
Few areas of conservation biology have grown at quite the same pace as conservation genetics. New Zealand exemplifies this growth with a 50–100-fold increase in publications since a review in 1994. A wide array of techniques in the fields of population genetics, molecular systematics and molecular biology has now become available to conservation bi...
Article
Full-text available
Aim Freshwater fish radiations are often characterized by multiple closely related species in close proximity, which can lead to introgression and associated discordance of mitochondrial and nuclear characterizations of species diversity. As a case in point, single locus nuclear versus mitochondrial analyses of New Zealand's stream‐resident Galaxia...
Preprint
Freshwater fish radiations are often characterized by multiple closely-related species in close proximity, which can lead to introgression and associated discordance of mitochondrial and nuclear characterizations of species diversity. As a case in point, single locus nuclear versus mitochondrial analyses of New Zealand’s stream-resident Galaxias vu...
Preprint
Processes responsible for population structuring across spatial and temporal scales represent key components in understanding speciation and evolution. We use a hierarchical approach to investigate the degree and mechanisms of structuring in landlocked and diadromous populations of the facultatively amphidromous fish Galaxias brevipinnis across var...
Article
Classic Mendelian inheritance is the bedrock of population genetics and underpins pedigree-based management of animal populations. However, assumptions of Mendelian inheritance might not be upheld in conservation breeding programs if early viability selection occurs, even when efforts are made to equalise genetic contributions of breeders. To test...
Article
Full-text available
Since the dawn of the discipline, biogeographers have wondered at the widespread distribution of galaxiid fishes throughout temperate regions of the Southern Hemisphere [...]
Article
Full-text available
Aim Repeated cycles of Pleistocene glaciation have influenced phylogeographic structure of taxa on New Zealand's South Island. Many taxa became restricted to refugia at either end of the island during glaciation, resulting in an area of low endemicity in central South Island. This area of low endemism is typified by the so‐called beech (or biotic)...
Article
Fourteen morphotypes of the Aden nerite (Nerita adenensis) from Chabahar Bay, the northern Gulf of Oman, were sequenced for mitochondrial cytochrome c oxidase I and nuclear ATPSα genes. COI sequences across all morphotypes yielded uncorrected intraspecific genetic distances (p) of between 0.013 and 0.017, whereas interspecific p was 0.11–0.16 among...
Article
Fourteen morphotypes of the Aden nerite (Nerita adenensis) from Chabahar Bay, the northern Gulf of Oman, were sequenced for mitochondrial cytochrome c oxidase I and nuclear ATPSα genes. COI sequences across all morphotypes yielded uncorrected intraspecific genetic distances (p) of between 0.013 and 0.017, whereas interspecific p was 0.11–0.16 among...
Article
Fourteen morphotypes of Aden Nerite (Nerita adenensis) from Chabahar Bay, the northern Gulf of Oman, were sequenced for mitochondrial cytochrome c oxidase I and nuclear ATPSα genes. COI sequences across all morphotypes yielded uncorrected genetic distances p = 0.013-0.017, whereas interspecific p = 0.11-0.16 among congeneric species. For ATPSα, acr...
Article
Full-text available
The Galaxiidae is a Southern Hemisphere family of freshwater fish, considered to be of Gondwanan origin based on the current distribution of species in New Zealand, Australia (including Tasmania), New Caledonia, Africa, South America, and on some associated and subantarctic islands. The fossil record of galaxiids is extremely sparse and geographica...
Article
New Zealand is a world leader in saving species from the brink of extinction. We selected seven case studies to explore successful species conservation in New Zealand over the past 30 years to exemplify what makes a ‘conservation winner’. The taxa chosen were: Hebe armstrongii, Mercury Islands tusked wētā, Galaxias vulgaris, tuatara, saddleback, lo...
Article
25 years ago, it was suggested that current‐day New Zealand, part of the largely sunken continent of Zealandia, could have been completely inundated during the Oligocene Marine Transgression (OMT) some 25–23 million years ago. Such an event would, of necessity, imply that all terrestrial, freshwater, and maybe coastal marine species must have dispe...
Chapter
Despite parallel revolutions of uniformitarianism in geology and gradualism in biology c200 years ago, it is now clear that rare events of large effect prevail in the natural world. While astronomical and geological phenomena are more overt (e.g. asteroid impact, supervolcanoes, earthquakes, tsunami), the general and widespread prevalence of major...
Article
Full-text available
Living species retain memories of their evolutionary history in their DNA, and that evolutionary history commonly reflects distinct geological events, such as mountain building and glaciation. We synthesize previously documented genetic data for freshwater fishes and a wide range of upland insect and bird species to document the Pliocene and early...
Article
Full-text available
Classification, phylogeography and the testing of evolutionary hypotheses rely on correct estimation of species phylogeny. Early molecular phylogenies often relied on mtDNA alone, which acts as a single linkage group with one history. Over the last decade, the use of multiple nuclear sequences has often revealed conflict among gene trees. This obse...
Article
Full-text available
Aim: Dispersal ability has traditionally been seen as a key influence on species distributions, but recent biogeographical analyses have cast doubt on the strength of this association. Here we present biogeographical evidence from New Zealand's entire plecopteran fauna (100 species) to test for associations between flight ability and species range,...
Article
This paper synthesises geological and biological data to develop an evolutionary history for the Taieri River that currently follows a circuitous 200 km course as one of the main drainages in Otago. The ancestral Taieri River drained only coastal hills initiated in the Miocene, and much of what is now the upper Taieri catchment flowed into the ance...
Article
Full-text available
The last century has seen an unparalleled movement of species around the planet as a direct result of human activity, which has been a major contributor to the biodiversity crisis. Amphibians represent a particularly vulnerable group, exacerbated by the devastating effects of chytrid fungi. We report the malicious translocation and establishment of...
Article
Full-text available
Collisions between tectonic plates lead to the rise of new mountain ranges that can separate biological populations and ultimately result in new species. However, the identification of links between tectonic mountain-building and biological speciation is confounded by environmental and ecological factors. Thus, there are surprisingly few well-docum...
Article
Full-text available
The fiords of southwestern New Zealand may promote the existence of genetically divergent populations as a result of geological and ecological isolation. The ophiuroid Astrobrachion constrictum lives on black coral in these fiords, and is thought to have a relatively short pelagic larval duration that may limit dispersal among populations. Samples...
Article
AimTo test the hypothesis that geomorphological features, shaped by underlying geology, can influence within-river connectivity patterns in freshwater-limited fishes.LocationRivers draining the eastern flanks of the Southern Alps in South Island, New Zealand.Methods We analyse up to 1624 bp of mtDNA from 499 ‘flathead’ Galaxias specimens from 145 l...
Article
The shape of hybrid zones provides insight into genetic isolation between the evolutionary lineages involved: the greater the limitation to gene flow, the farther along the unimodal to bimodal continuum. We study hybrid zone modality in a group of closely related species at a variety of levels of genetic divergence. We explore the degree and the ge...
Chapter
Full-text available
We describe protein sequences for a uromodulin-like larval glycoprotein (LGP) from 21 species of galaxiid fishes, with a MRCA about 30 Ma. These have been derived from both genomic DNA and cDNA, by conventional and Roche 454 sequencing. LGP shows a fast rate of evolution and an exceptionally strong signal of positive selection over the entire codin...
Article
Over the past two decades, behavioural biologists and ecologists have made effective use of the comparative method, but have often stopped short of adopting an explicitly phylogenetic approach. We examined 68 behaviour and life history (BLH) traits of 15 penguin species to: (i) infer penguin phylogeny, (ii) assess homology of behavioural characters...
Article
Full-text available
Variation among complete cytb sequences (1140 bp) of Aphanius mesopotamicus Coad, 2009 was compared with closely related species, to investigate the validity of this taxon as a newly-described tooth-carp based on morphological characteristics. Maximum likelihood and Bayesian likelihood trees supported the monophyly of A. mesopotamicus and its siste...
Article
Full-text available
Toll-like receptors (TLRs) are a family of conserved pattern-recognition molecules responsible for initiating innate and acquired immune responses. Because they play a key role in host defence, these genes have received increasing interest in the evolutionary and population genetics literature, as their variation represents a potential target of ad...
Article
During population establishment, genetic drift can be the key driver of changes in genetic diversity, particularly while the population is small. However, natural selection can also play a role in shaping diversity at functionally important loci. We used a well-studied, re-introduced population of the threatened Stewart Island robin (N = 722 pedigr...
Article
Full-text available
We write to convey our concerns that some mainstream evolutionary journals continue to publish articles that, in our view, present misleading accounts of biological evolution. Specifically, we argue that "panbiogeographic" studies of spatiotemporal biological history (e.g., Craw 1988; Heads 2010a, 2010b, 2011, 2012a, 2012b) are detrimental to the p...
Article
Full-text available
Toll-like receptors (TLRs) are an ancient family of genes encoding transmembrane proteins that bind pathogen-specific molecules and initiate both innate and adaptive aspects of the immune response. Our goal was to determine whether these genes show sufficient genetic diversity in a bottlenecked population to be a useful addition or alternative to t...
Data
Alignment of clone haplotypes obtained for two individuals amplified at TLR7 showing character states at variable sites; all other base positions were monomorphic. (DOCX)
Data
McDonald-Kreitman tests contrasting substitution and mutation rates for a comparison of P. a. rakiura TLR sequences with those of C. mexicanus [23] . (DOCX)
Data
Neighbour-joining tree of TLR7 sequences available for nine avian genera. (DOCX)
Article
Full-text available
Phylogeography contributes to our knowledge of regional biotas by integrating spatial and genetic information. In New Zealand, comprising two main islands and hundreds of smaller ones, phylogeography has transformed the way we view our biology and allowed comparison with other parts of the world. Here we review studies on New Zealand terrestrial an...
Article
Full-text available
Reintroduction guidelines recommend that ‘adequate’ numbers of individuals be released to minimize loss of genetic diversity, but these numbers are rarely quantified. We present a framework for assessing the number of individuals required for an island reintroduction that takes account of allele loss both during the founding event and in the follow...
Article
Full-text available
Length-weight relationships were estimated for 16 populations of six Iranian toothcarp species. Differences between sexes were statistically significant for two of the species.
Article
Full-text available
Mechanisms of speciation are best understood in the context of phylogenetic relationships and as such have often been inferred from single gene trees, typically those derived from mitochondrial DNA (mtDNA) markers. Recent studies, however, have noted the potential for phylogenetic discordance between gene trees and underlying species trees (e.g., d...
Article
1. Numerous interacting abiotic and biotic factors influence niche use and assemblage structure of freshwater fishes, but the strength of each factor changes with spatial scale. Few studies have examined the role of interspecific competition in structuring stream fish assemblages across spatial scales. We used field and laboratory approaches to exa...
Article
The origin of the New Zealand "beech gap," a low-diversity zone in the central South Island corresponding with a disjunction in the distribution of many taxa, has been the focus of biogeographical debate for many decades. Here, we use comparative phylogeographic analysis (COI; H3) of six alpine stonefly genera (116 individuals, 102 localities) to t...
Article
Wing reduction and flightlessness are common features of alpine and subalpine insects, and are typically interpreted as evolutionary adaptations to increase fecundity and promote local recruitment. Here, we assess the impact of wing reduction on dispersal in stoneflies (Plecoptera: Gripopterygidae: Zelandoperla) in southern New Zealand. Specificall...
Article
Full-text available
Morphometrics and amplified fragment length polymorphisms (AFLPs) were used to examine interspecific differentiation and intraspecific variation in two closely related freshwater fishes (Galaxias ’southern’ and G. gollumoides) using sympatric and allopatric populations. The two species were strongly differentiated across all populations, showing 19...
Article
Full-text available
Hybridisation between related taxa has a range of possible biological consequences, ranging from the production of sterile offspring, through introgression of alleles into populations, to the formation of new species. Examples of plant and animal species hybridising with related taxa abound in the New Zealand region. We review New Zealand examples...
Article
The majority of reported multilocus heterozygosity-fitness correlations (HFCs) are from large, outbred populations, and their relevance to studies on inbreeding depression in threatened populations is often stressed. The results of such HFC studies conducted on outbred populations may be of limited application to threatened population management, h...
Article
Full-text available
Hybridization between divergent lineages often results in reduced hybrid viability. Here we report findings from a series of independent molecular analyses over several seasons on four life stages of F1 hybrids between the newts Triturus cristatus and T. marmoratus. These two species form a bimodal hybrid zone of broad overlap in France, with F1 hy...
Article
We compared historic and contemporary genetic variation in two threatened New Zealand birds (saddlebacks and robins) with disparate bottleneck histories. Saddlebacks showed massive loss of genetic variation when extirpated from the mainland, but no significant loss of variation following a severe bottleneck in the 1960s when the last population was...
Article
Tectonic movement at the boundary of the Indo-Australian and Pacific Plates during the Miocene and Pliocene is recognized as a driving force for invertebrate speciation in New Zealand. Two endemic freshwater crayfish (koura) species, Paranephrops planifrons White 1842 and Paranephrops zealandicus White 1842, represent good model taxa to test geolog...
Article
Full-text available
We highlight a novel molecular clock calibration system based on geologically dated river reversal and river capture events. Changes in drainage pattern may effect vicariant isolation of freshwater taxa, and thus provide a predictive framework for associated phylogeographic study. As a case in point, New Zealand's Pelorus and Kaituna rivers became...
Article
We used mtDNA and isozyme analysis of a freshwater fish, Galaxias divergens (Osmeriformes: Galaxiidae), to test a hypothesis of drainage evolution in South Island, New Zealand. Geological evidence indicates that the presently north-flowing Kaituna River branch of the Pelorus River system once flowed south into the Wairau River system. The subsequen...
Article
There is growing evidence that inbreeding can negatively affect small, isolated populations. This contrasts with the perception in New Zealand, where it has been claimed that native birds are less affected by inbreeding depression than threatened species from continental regions. It has been argued that New Zealand's terrestrial birds have had a lo...
Article
Full-text available
Lake systems are often notable for the diversification of freshwater fish species. This has yet to be documented in New Zealand, although a possible case has been described in Galaxias brevipinnis from Lake Okareka, where lake‐ and stream‐resident fish show morphological and ecological differences. Samples of G. brevipinnis collected from three New...
Article
Full-text available
Body colour is an important distinguishing feature in a New Zealand alpine weta hybrid zone and is strongly correlated with mitochondrial DNA haplotype variation. To assess the broader geographic pattern of this association, an intraspecific phylogeny was generated using mtDNA sequence. Both parsimony and likelihood analyses separated the colour mo...
Article
Tension zones are maintained by the interaction between selection against hybrids and dispersal of individuals. Investigating multiple hybrid zones within a single species provides the opportunity to examine differences in zone structure on a background of differences in extrinsic factors (e.g., age of the zone, ecology) or intrinsic factors (e.g.,...
Article
Full-text available
We used mitochondrial DNA sequences to determine the phylogenetic placement of southern smelts (Retropinnidae), a group of diadromous fishes endemic to New Zealand and Australia. Our genetic data strongly support a sister group relationship between retropinnids and northern hemisphere smelts (Osmeridae), a relationship that seems consistent with th...