PEARG research blog

Using bacteria to control mosquitoes Dr Tom Schmidt and Professor Ary Hoffmann “This article was first published on Pursuit. Read the original article.” Living inside the cells of insects is a type of bacteria that is looking increasingly like the key to controlling the spread of dengue fever, the Zika virus and other mosquito-borne diseases. The Wolbachia bacteria, which occurs naturally in about half …

Words: Ary Hoffmann One of the central tenets of conservation biology is that high levels of genetic variation in natural populations is important for their long-term survival. High levels of variation allow populations to adapt to changing environments through evolution. This process is now recognised as being extremely fast when selection pressures are high. In fact many populations of animals and …

We are seeking motivated MSc students to apply for several projects starting next year. Enquiries via pearg-queries@unimelb.edu.au Project 1/4: Exploring bacterial symbionts for agricultural pest control PEARG is researching ways to control important agricultural pests such as aphids and mites that cause millions of dollars in damage to crops each year in Australia. This project will involve testing the potential for endosymbiotic …

NEW paper! Dispersal is a key component of the ecology and evolution of animal populations. It allows animals to colonize new habitats, escape deteriorating conditions, and locate mates. When animals disperse and breed successfully in new habitats that are already occupied by the same species, there will be an exchange of genes. This exchange is essential in maintaining the health of …

Original article published on The Conversation Words: Tom Schmidt, Andrew Weeks, and Ary Hoffmann We might not be able to use common insecticides to kill mosquitoes that arrive from other countries. from www.shutterstock.com Planning a trip to the tropics? You might end up bringing home more than just a tan and a towel. Our latest research looked at mosquitoes that travel as secret stowaways on …

Words and images: Oliver Stuart Link to open access paper Earwigs (Dermaptera) are a challenging group of insects to study. In Australia, earwigs are variously known as pests, predators of pests (so, beneficial insects), or both at once depending on the crop type and other particulars. The invasive Forficula auricularia (the European earwig) is the most common pest, but we also have …

A recent review paper in Biological Conservation by Francisco Sánchez-Bayoa and Kris Wyckhuys has sparked considerable media attention on the plight of insects and the need to conserve them. In amongst the noise, PEARGs own Linda Thomson was interviewed by The New Daily about what you can do in your own back yard to help.    

The National Environment Agency of Singapore released Wolbachia infected male mosquitoes last April in order to suppress the local population. The field study has been a fantastic success with an 80% population reduction achieved in the last nine months. Ary is a member of Singapore's Dengue Expert Advisory Programme, providing expertise and guidance for the program. Read more about it …

With temperature records being smashed around Australia people are paying ever more attention to climate change. As Adelaide has set a new record maximum temperature ABC's Adelaide reporter Malcolm Sutton interviewed Ary for an article, loosely based around our open access review in Austral Ecology

Header photo: Marianne Coquilleau, Samantha Ward, Xuan Cheng, Josh Douglas, Tom Schmidt and Oliver Stuart  Words: Oliver Stuart and Samantha Ward Introduction This past September was the 49th Annual General Meeting and Scientific Conference of the Australian Entomological Society (AES). The Society publishes an Australia-focused journal and maintains, through its membership, a network of professional and student entomologists. Every year the network …

Words: Daronja Trense Images: Daronja Trense & Klaus Fischer One of the projects of my PhD is to investigate the genetic connectivity of the Copper butterfly (Lycaena tityrus) in the Ötzvalley of the European Alps. In summer 2018, we collected 186 butterflies to understand how the geological structure of the valley has influences the genetic constitution of L. tityrus. PEARG provided me the …

Please follow this link to Ary's recent interview on Three Triple R FM

Words and images: Perran Ross Mosquitoes in the wild live it rough. Adult females risk being swatted as they search for a blood meal and their larval progeny must fend off predators and compete for limited resources. When we want to study mosquitoes under controlled conditions we bring them into the laboratory, but these conditions often don’t reflect their natural environment. …

Words: Nick Bell Header image: Johan Larson, Department of Tropical Biology, James Cook University Together with a team of experts from across Australia, PEARG has recently published an open access review in Austral Ecology. The review outlines eight case studies which demonstrate the effects of climate change on the nation’s native flora and fauna. We’ve also put together a summary article …

Words and images: Ann Stocker Rhynchosciara species are endemic to South and Central America. The larvae are readily observed because they are a centimeter or more in length, usually reddish in colour and travel in groups of dozens to hundreds of individuals (Fig 1). However, they only came to the attention of biologists after Crodowaldo Pavan, a Professor at the University …

Words: Samantha Ward If I ask you what is involved in studying for a PhD, a Doctor of Philosophy, a higher or postgraduate degree in science, what do you envisage? The terms are different, but I’m sure the image is the same. How do you imagine a Science PhD? Credit: Cindy Schultz via Flickr Most people would likely describe the endless monotony of writing …

Words: Samantha Ward The duck-billed platypus has always been something of an enigma. When the first pelt and sketch were sent back to Europe at the end of the 18th century, many British scientists refused to accept the platypus was a real organism. Instead, they believed it was an assortment of animal parts that had been sewn together as a hoax. Its duck-like …

Words: Samantha Ward Friend or foe? When you look at your fluffy pet cat curled up beside you on the sofa, do you see a cute companion or a calculating killer? Cute companion or calculating killer? Credit: Author’s own. I’m going to assume the former, but now let me ask you this: Do you let your cat outside, even for five minutes a day? …

Words: Samantha Ward We’re going to the zoo, zoo, zoo. How about you, you, you…?” Perhaps you remember singing the song when you were a child. If you do, you probably have it stuck in your head now! If you don’t, I’m sure you remember those fun-filled zoo days watching gigantic elephants spraying themselves with water, nose pressed against the glass looking …

Image credit: Zootaxa Congratulations to Ann for being recognised for her extensive contributions to our understanding of Australian flies. A species of Victorian fungus gnat (Diptera: Sciaridae) has been formally described and named Austrosciara stockerae. You can read about the taxonomic details in a recent Zootaxa article here. The dedication blurb A bit about Ann from her profile; Ann Stocker, Honorary Research …

Words and images: Vanessa White Some important lessons learnt and new questions around Vandiemenella laboratory rearing In the previous grasshopper blog, I reported “reasonable success with room for improvement” in our attempts to rear Vandiemenella grasshopper nymphs in the laboratory. Alternative housing is an important focus for improvement, but a discussion with Mike and Ary raised the question of differing food requirements …

Words: Vanessa White Images: Mike Kearney and Vanessa White Why Australian grasshoppers are fantastic research subjects: The Morabine grasshoppers (subfamily Morabinae) commonly known as “matchstick grasshoppers” are endemic to Australia and comprise 40 genera and around 250 species (Rentz 1996). Both sexes are wingless with a characteristic matchstick-like appearance. Some Morabine species have been studied in detail due to their interesting life …

Words: Mengjia Liu Images: Perran Ross and Mengjia Liu It is important to study the fitness of different colonies of Wolbachia-infected mosquitoes, and also of interest to test fitness effects within the same colony when mosquitoes are maintained under different conditions. As we have been maintaining uninfected mosquitoes under laboratory conditions for over 25 generations, one question emerges: What is the difference …

Aedes notoscriptus has been identified in association with the emerging bacterial pathogen Mycobacterium ulcerans, which causes Buruli ulcer, as well as being a vector of Ross River virus. Key ecological features such as bloodmeal feeding patterns and movement dynamics of individuals are however not clearly defined. This project will involve both laboratory and field-based components. Field collections will be conducted in …

Words: Anne Aulsebrook Cover image: Mount Rothwell Conservation and Research Centre An article published in 1934 describes the flavour of bandicoot stew. ‘After chewing a mouthful I gave up.’ The writer states, ‘The stew tasted like roots. I have not sampled stewed bandicoot since.’ At the time of the article, bandicoots in Australia were already under threat. While not favoured by the writer, bandicoots …

Words: Linda Thomson Image: Zagrammosoma latilineatum by Elia Pirtle Along with sustainability, biodiversity is a current catchword. Our work demonstrating the benefits of non crop vegetation on increasing biodiversity and especially "beneficials' which contribute to pest control in crops. Enthusiasm for the project is shown by the excellent attendance at a recent workshop – report of which has been highlighted as an …

Words: Ary Hoffmann Cover image: John Gould 1863   As featured recently in a Pursuit piece, we are making steady progress with the genetic rescue of eastern barred bandicoots through our joint work with Mt Rothwell sanctuary. Genetic rescue provides a way of introducing new genetic material into threatened populations which in turn allows these populations to increase their fitness and ability to …

Words: Ary Hoffmann Cover image: Perran Ross As Wolbachia bacteria that live inside insect cells continue to be discovered and studied in detail, our appreciation of the diverse ways in which these bacteria interact with their hosts continues to expand. In past work we have found Wolbachia that cause embryo death when infected males mate with uninfected females (“cytoplasmic incompatibility”), Wolbachia that …

Words and video: Perran Ross I recently filmed one of our mosquito colonies trying desperately to reach my arm through their enclosure. The video has been posted on Reddit by a third party and received enormous attention with over 4.5 million views in its first nine hours. To make the video, I held my arm next to a cage of Aedes aegypti …

Excellent design by Elia Pirtle, as you can see our beleaguered website manager hasn't quite figured out how to make it work as a banner image on this site.

A new paper is out in Frontiers in Marine Science - article link A nicely digestible review of the article is available at Ocean bites here

Words and images: Perran Ross Large male mosquitoes may have more trouble than smaller males in finding a partner. In a new study, we find that small female mosquitoes tend to avoid larger males, preferring to mate with smaller ones. In this study, now available as a pre-print on bioRxiv, we performed laboratory experiments to investigate the effect of male and …

Author summary and figures by Tom Schmidt Wolbachia is a bacterium that suppresses the capacity for arbovirus transmission in the mosquito Aedes aegypti, and can spread spatially through wild mosquito populations following local introductions. Recent introductions in Cairns, Australia have successfully established Wolbachia in the Ae. aegypti population, but the infection has spread more slowly than expected through the surrounding area. Potential reasons …

Header photo by Museums Victoria, CC BY. Photographer: Rodney Start Original broadcast Sunday 20 May 2018 http://www.abc.net.au/radionational/programs/sciencefriction/insect-armageddon/9775654  

Words and photo: Jason Axford On 26 April at the Peter Doherty Institute, Federal Minister for Health, Greg Hunt, announced new NHMRC funding to investigate the mysterious and rather horrific disease commonly known as Buruli ulcer (BU) (formerly known as Bairnsdale ulcer). The project is led by Prof. Tim Stinear in the Department of Microbiology and Immunology at the Peter Doherty Institute …

Words and photo: Xuan Cheng This research has been published in the Journal of Economic Entomology The redlegged earth mite, Halotydeus destructor (Tucker) (Trombidiformes: Penthaleidae) is a polyphagous economic pest in Australia, attacking a broad range of host plants in broadacre farming systems1. Although applications of pesticides are currently the main method in managing earth mites, resistance against pyrethroid and organophosphate chemicals …

Words: Samantha Ward As the name suggests, at the Pest & Environmental Adaptation Research Group we are interested in pest species and enjoy investigating novel approaches to sustainably control such organisms. I began my PhD at PEARG in 2016 studying parasitoid wasps; A group of wasps that lay their eggs inside or onto other arthropods. Parasitoids differ from parasites because they …

Editors note: This article is direct from our internal research diary Words: Nancy M. Endersby-Harshman The purpose of this article is to recommend very careful reading and analysis of the literature relating to sodium channel mutations in Aedes aegypti and equal care in writing about them. I have uncovered some confusion in the mosquito literature about the kdr triple resistance mutation in the …

Tune in to 3RRR 102.7 FM between 7-8 this evening to hear Ary in discussion about all things insect ecology. If you miss it or live too far from Melbourne to tune in, you can stream the show live at rrr.org.au or after it airs at https://www.rrr.org.au/program/greening-the-apocalypse/ 3RRR is a Melbourne based community radio station, this show in particular is usually quite …

Off the back of a review Ary wrote last year in Current Opinion in Insect Science, a less technical and more digestible summary is now available (sans pay-wall) at Science Trends. A Quote from the Science Trends article to grab your interest: Evolutionary changes often occur when pest species invade new areas where they have not been found before ... Pests are …

Words: Tom Schmidt Photos: Tom Schmidt and Perran Ross At PEARG, we have a great interest in environmental pests and how to deal with them. One of these pests is the mosquito Aedes aegypti, which causes catastrophic damage throughout the world’s tropical zone. Aedes aegypti spreads viruses such as dengue, Zika and chikungunya, and is highly adept at invading new regions around …

Words: Perran Ross Cover photo: Andrew Weeks Wolbachia are perhaps the most prevalent bacterial symbionts on earth. Of the millions of insect species, Wolbachia are estimated to infect up to half of them. These bacteria are renowned for the effects they exert on their hosts, which can often be quite dramatic. Some Wolbachia strains are highly pathogenic; for instance, the wMelPop, or …

Words and images: Perran Ross Cover photo: Jason Axford Dengue is a major global health issue. It infects millions of people every year and can cause debilitating illness, inflicting joint pain, rash and fever. Without any effective vaccine, the best way to prevent dengue is to target the mosquitoes that transmit it. Dengue is spread by Aedes mosquitoes, and we’ve been waging …

Nancy, Andrew and Ary have a fresh review article in CSIRO's 'Microbiology Australia' journal. Below is the abstract, for the full text please follow this link. Mosquito-borne arboviruses are increasing in incidence around the world. Australia enjoys some protection from pests and diseases afforded by its geographic isolation coupled with strict biosecurity control at its borders. However, as the volume of …

Written by Oliver Stuart, Image credit: Ryan Hodnett [CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0)], from Wikimedia Commons There are a lot of different insects; this cannot be overstated. Of the roughly 2 million animal species (that we know of), insects make up well over half. This mega-diversity has been a source of delight for biologists for centuries, but it has also caused no …

Progress! For those unfamiliar, the Flora and Fauna Guarantee Act 1988 is "the key piece of Victorian legislation for the conservation of threatened species and communities and for the management of potentially threatening processes.", you can find more information onthe act and it's significance for protecting threatened species in Victoria at the DELWP website. You can read the full Scientific Advisory Committee's …

Perran and Ary's lab adaptation review  paper is fresh off the press and immediately generating interest. Follow the link below to Entomology Today to read all about it. https://entomologytoday.org/2018/03/01/study-shows-rapid-evolution-in-lab-reared-insects/

Words: Ellen Cottingham Image: Perran Ross Most Australians have sat outside on a summers evening only to return inside to find their legs and arms dotted with fresh itchy mozzie bites. It is not widely known that only female mosquitoes bite warm blooded animals or humans. The reason for this is that females use protein and iron from the blood to help …

Climate contributes to the evolution of pesticide resistance | James Maino, Paul Umina, Ary Hoffmann     AbstractThe evolution of pesticide resistance through space and time is of great economic significance to modern agricultural production systems, and consequently, is often well documented. It can thus be used to dissect the evolutionary and ecological processes that underpin large-scale evolutionary responses. There are now …

Mike Kearney was interviewed on The ABC's Victorian Country hour on Friday. Link below, interview begins 38:40. Victorian Country Hour for Friday 16th February 2018