Prof Steven Trewick staff profile picture

Contact details +6469517842

Prof Steven Trewick

Professor in Evolutionary Ecology

School of Agriculture and Environment

For more information about the research I do please have a look at our team website evolves.massey.ac.nz, just click the URL

I am fascinated by the same 'grandeur' in the way that life has developed on our planet that beguiled Charles Darwin. As a result my interests are diverse and dynamic extending to the composition of biotas and ways that biotas develop; the way species evolve and interact and the way interactions evolve; the definition and description and significance of biodiversity, the classification, taxonomy and systematics of life on earth and its conservation, and much more.

I am in interested in how, why and when species form.  Why do assemblages have the species they do?  To what extent is this a product of rare events such as dispersal and continental vicariance  vs ecological adaptation? How do species evolve as they interact with other plants and animals and the physical environment?  Modern research tools are allowing inferences about past processes to be melded with observations of current changes in communities, species and populations, that result from environmental change that is the direct result of excessive exploitation of the Earth by humans.

The NZ archipelago has ancient geological links with other (Gondwanan) landmasses, and harbours some organisms of ancient pedigree, but many taxa appear to be the products of recent colonisation or radiation.  I am interested in the use of ecological and molecular approaches to help understand the process that lead to the distributions and interactions of species.  I am particularly interested in endemic invertebrates including peripatus, weta, carabid beetles and stick insects.  Studies of these taxa involve comparison with relatives in neighbouring regions (Australia, New Caledonia etc).  I also work on birds, exploring evolution of flightlessness and species radiations associated with Pacific Islands.

More about me...View less...

Professional

Contact details

  • Ph: +64 6 356 9099 ext 84842
    Location: 1.18, AgHort A
    Campus: Manawatu

Research Expertise

Research Interests

For more information please refer to the website of our research team 'Phoenix Lab' at http://evolves.massey.ac.nz/

I am in interested in how, why and when species form.  Why do assemblages have the species they do?  To what extent is this a product of historical events such as dispersal, vicariance and extinction, vs ecological adaptation? How do species evolve as they interact with other plants and animals?

The NZ archipelago has ancient geological links with other (Gondwanan) landmasses, and harbours some organisms of ancient pedigree, but many taxa appear to be the products of recent colonisation or radiation.  I am interested in the use of ecological and molecular approaches to help understand the process that lead to the distributions and interactions of species.  I am particularly interested in endemic invertebrates including peripatus, weta, carabid beetles and stick insects.  Studies of these taxa involve comparison with relatives in neighbouring regions (Australia, New Caledonia etc).  I also work on birds, exploring evolution of flightlessness and endemism more generally.

Molecular tools have contributed much to our understanding of ecology and testing questions about adaptation, but an interest and understanding of whole organism biology is essential.  Good research requires good questions and these come from observing the natural world.  Molecular tools provide a means to look at nature in both a space (geography) and time.  Often it is possible to test ideas about the behaviour and ecology of organisms using genetic markers that cannot (or not easily) be viewed directly, and as such can be a useful addition to field studies.  Similarly population genetic methods can help research on conservation, and explore the interactions between related species where they meet and interact ecologically and reproductively.

Some recent/current projects include:

  • · Evolutionary ecology of alpine grasshoppers.
  • · Global phylogeography of swamphens (Porphyrio)
  • · Microendemism of micorsnails.
  • · Seed predation by tawa moth.
  • · Evolutionary genetics of brush-tailed possum.
  • · Mate location and choice in stick insects.
  • · Diet and ecophysiology of tree weta
  • · Sexual selection and diversity in the ground weta.
  • · Systematics and population genetics of cave weta.
  • · Deep time diversification of rails.
  • · Ecology and population genetics of weka (Gallirallus australis).
  • · Evolutionary rates in New Zealand marine molluscs (fossils and DNA).
  • · Conservation genetics of Powelliphanta land snails.
  • · Behaviour and phylogeny of Fijian honeyeaters.
  • · Southern hemisphere biogeography of weta.
  • · Feeding ecology and biodiversity of the Fijian longhorn beetles
  • · Speciation and evolution of flightless rails (Rallidae).
  • · Conservation of Philippine crocodile.
  • · Reproductive and ecological interactions at tree weta contact zones
  • · Seed predation and plant/insect mutualisms.
  • · Host-parasite interactions in cabbage aphid.

Area of Expertise

Field of research codes
Biological Sciences (060000): Ecology (060200):
Environmental Sciences (050000):
Evolutionary Biology (060300): Genetics (060400): Genomics (060408): Invertebrate Biology (060808): Molecular Evolution (060409): Population, Ecological and Evolutionary Genetics (060411):
Studies In Human Society (160000):
Zoology (060800)

Keywords

Species, evolution, biogeography, biodiversity, evolutionary ecology, environmental sustainability, science communication

Research Projects

Summary of Research Projects

Position Current Completed
Project Leader 3 20
Team Member 1 1

Current Projects

Project Title: Why fly when you can walk? Genetic pathways to flightlessness

Date Range: 2017 - 2021

Funding Body: Royal Society of New Zealand

Project Team:

Completed Projects

Project Title: Punctuated evolution: is rapid morphological change linked to speciation?

The study of fossils provides an impression of morphological evolution made up of long periods of constrained evolution when nothing changes interspersed with geologically sudden leaps in form. Many interpret these abrupt changes in morphology as being the result of speciation (punctuated equilibrium). Other explanations for this pattern are possible and include rapid adaptation without speciation, the invasion of species from elsewhere, or hybridisation. New Zealand has one of the world's best fossil records for marine snails and many lineages in the rocks have relatives alive today. For the first time we can study the morphology and the molecular evolution of the same snail lineages united to produce a time-space integrated view of phenotypic divergence. This project brings together a unique combination of paleontologists, molecular geneticists and phylogeographers to study speciation in the past and present. Using mathematical analysis of shell shape changes and the latest DNA sequencing tools we will determine whether the timing of morphological change coincides with speciation inferred from molecular phylogenetics. By answering the fundamental question 'Is morphological change the result of species formation'. We will place New Zealand at the forefront of speciation research internationally.
Read Project Description Hide Project Description

Date Range: 2013 - 2016

Funding Body: Marsden Fund - Full

Project Team:

Project Title: MSI - Postdoc Fellowship - Simon Hills - Population and community structure of East Coast marine molluscs

Effective management of ecological recourses is contingent on access to quality information about organisms and environment. For Maori, a comprehensive understanding of the structure of New Zealand's biodiversity is particularly valuable for considering traditional management practices such as mataitai and taiapure, and for management of iwi fishing resources. Such basic biodiversity data is critical for the identification of areas that will make the most appropriate marine reserves, and for the long-term evaluation of marine reserves. The structure of populations and communities of organisms in New Zealand is of particularly interesting due to the diverse and highly dynamic nature of the local environment. This dynamism has had a profound effect on the phylogeographic patterns of species found in New Zealand (Wallis and Trewick 2009). However, the marine environment is currently relatively underrepresented in such studies. Significant research has been devoted to a small selection of mostly commercially harvested species (e.g. paua, crayfish, fin-fish), and places of interest (e.g. Hayward 1997, Taylor and Morrison 2008). However, the greater part of the New Zealand marine biodiversity is relatively poorly understood. A key question in the consideration of the current biodiversity is how it changes over time. Specifically, where did it come from and how is it likely to change in the future?
Read Project Description Hide Project Description

Date Range: 2011 - 2014

Funding Bodies: Ministry of Business, Innovation and Employment; Use MINBIE -- Ministry of Science and Innovation

Project Team:

Project Title: What limits a weta?

The distribution of a species is controlled by a combination of environmental factors and biotic interactions. For example temperature must be warm enough to allow growth, and the right foods must be available in the environment. We investigated the factors limiting the expansion of the range of the common Wellington tree weta species Hemideina crassidens. We inferred past range changes from patterns of genetic diversity over its range, and examined the competitive interactions that might prevent sympatry with the Auckland tree weta. We are investigating adaptation to high and low elevation sites that might allow the species to expand its range and the potential role of gene flow in limiting adaptation.
Read Project Description Hide Project Description

Date Range: 2010 - 2013

Funding Body: Massey University

Project Team:

Teaching and Supervision

Teaching Statement

I teach evolution, biogeography, environmental science, zoology and ecology from first year undergraduate to PhD.

Paper coordinator for New Zealand Environments (121.103) and Biological Evolution (196.207). I also teach into Animal Biodiversity (199.317) and graduate papers including Topics in Biodiversity (199.719), Entomology (199.717) and Conservation Biology (232.701).

I supervise numerous PhD and MSc graduates and have research collaboration with scientists in New Zealand, Australia, South America, Japan and France.

Courses Coordinated

Summary of Doctoral Supervision

Position Current Completed
Main Supervisor 3 7
Co-supervisor 3 8

Current Doctoral Supervision

Main Supervisor of:

  • Nim Pattabiraman - Doctor of Philosophy
    Landscape genetics of brushtail possums in New Zealand
  • David Carmelet-Rescan - Doctor of Philosophy
    Evolutionary genetics of brush tail possums.
  • Julien Gaspar - Doctor of Philosophy
    Why fly when you can walk? Genetic pathways to flightlessness in birds.

Co-supervisor of:

  • Mari Nakano - Doctor of Philosophy
    Grasshopper-Host Plant associations in the New Zealand alpine grasslands
  • Michelle Guerrero - Doctor of Philosophy
    Environmental diversity of entomopathogenic fungi and their interactions with arthropod hosts
  • Mathieu Quenu - Doctor of Philosophy
    Evolution, climate, snail shells and oxygen isotopes.

Completed Doctoral Supervision

Main Supervisor of:

  • 2018 - Emily Koot - Doctor of Philosophy
    The Ecology and Evolution of New Zealand’s Endemic Alpine Grasshoppers
  • 2018 - Kathleen Walker - Doctor of Philosophy
    Systematics and Phylogeography of the large land snail: Powelliphanta
  • 2017 - Josephine Fitness - Doctor of Philosophy
    Te Putaiao o Tokoriro: Taxonomy and diversity of New Zealand cave weta (Orthoptera: Rhapidophoridae)
  • 2016 - Santhi Bhavanam - Doctor of Philosophy
    Effect of nutrient limitation on the Mediterranean flour moth, Ephestia kuehniella Zeller
  • 2015 - Briar Smith - Doctor of Philosophy
    Evolution of diversity: Analysis of species and speciation in Hemiandrus ground weta
  • 2014 - Edwina Dowle - Doctor of Philosophy
    Rates of Molecular Evolution and Gene Flow
  • 2011 - Julia Goldberg - Doctor of Philosophy
    Speciation and phylogeography in the New Zealand archipelago

Co-supervisor of:

  • 2019 - Suman Sran - Doctor of Philosophy
    Assessing the sustainability of anticoagulant-based rodent control for wildlife conservation in New Zealand
  • 2017 - Felix Vaux - Doctor of Philosophy
    Evolutionary lineages and the Diversity of New Zealand true whelks
  • 2017 - Michael Gemmell - Doctor of Philosophy
    Genetic and Phenotypic Lineages in Neogastropod Molluscs: A Journey Through Time and Morphospace
  • 2017 - Elizabeth Daly - Doctor of Philosophy
    Fine scale population structure through space and time.
  • 2014 - Juan Carlos Garcia Ramirez - Doctor of Philosophy
    The influence of space and time on the genetic architecture of rail species (Aves:Rallidae)
  • 2012 - Prasad Doddala - Doctor of Philosophy
    Systematics of Eucolaspis (Coleoptera: Chrysomelidae) in New Zealand and ecology of Hawke's Bay lineage
  • 2012 - Rashmi Kant - Doctor of Philosophy
    Reproductive behaviour and fitness trade-offs in the aphid parasitoid Diaeretiella rapae (Hymenoptera: Aphidiidae)
  • 2010 - Simon Hills - Doctor of Philosophy
    The evolution of a marine gastropod genus: Rocks, clocks and convergence

Media and Links

Contact us Mon - Fri 8:30am to 4:30pm 0800 MASSEY (+64 6 350 5701) TXT 5222 contact@massey.ac.nz Web chat Staff Alumni News Māori @ Massey