Posts

, , , ,

Love, Tiny Flies, and One Big Opportunity for Researchers to Work Together Helping Farmers on Both Sides of the Border ~ Foreign Perspectives

Me at the University of Guelph Elora Research Station.

by Elisabeth Hodgdon, Ph.D. Candidate, University of Vermont

“It’s a story of unrequited love,” says Dr. Yolanda Chen, my Ph.D. advisor, describing our research on pheromone mating disruption. Mating disruption, a pest management strategy that involves inundating a field with synthetic sex pheromone, prevents male insects from finding their mates because they can’t cue in on individual female pheromone plumes. As a result, the males become confused and die without mating. During my time as a Ph.D. student, I’ve spent a lot of time in Vermont and Ontario becoming intimately familiar with the sex lives of swede midge, a serious invasive pest of cruciferous crops.

Swede midge (Contarinia nasturtii, Diptera: Cecidomyiidae) first arrived in North America in the 1990s in Ontario. Vegetable growers started noticing that their broccoli, cauliflower, and cabbage plants were deformed and didn’t produce heads, and that their kale leaves were twisted and scarred. On canola farms, yields decreased because of distorted plant growth. The culprit, identified by Dr. Rebecca Hallett and her research group from the University of Guelph, was a tiny fly called swede midge. The midge, only about 2 mm long as an adult, is seemingly invisible to farmers because it is so small. Within a few years, the midge had made its way from Ontario to Québec and other provinces, and into New York and Vermont.

Female swede midge on cauliflower.

At the University of Vermont, we are the only research lab in the US working on this pest, which is currently causing up to 100% yield loss of organic broccoli and kale in our state. Naturally, it made sense for Dr. Chen to reach out to Dr. Hallett in Guelph for collaboration to investigate management options for this pest. Together, they wrote a grant funded by the USDA to conduct pheromone mating disruption research on swede midge that would take place in both Vermont and in Guelph.

This where I enter into the story. I jumped at the opportunity to join Dr. Chen’s lab, not just because I’m interested in insect pest management, but also because of my continuing love affair with Canada. I grew up in Vermont, a small state that borders Québec and has had lots of influence from our northerly neighbors: a history of French-Canadian immigrants, widespread availability of decent quality poutine, and signage in our largest city en français, among other things. I grew up learning French and visiting nearby Montréal and later went on to study agriculture at McGill University’s Macdonald Campus. I was thrilled at the opportunity to spend more time in Canada during my Ph.D. program.

Me and University of Guelph entomology graduate students at the ESC meeting in Winnipeg last fall: Charles-Étienne Ferland, Jenny Liu, me, Sarah Dolson & Matt Muzzatti (left to right). Photo credit: Matt Muzzatti.

I have gotten to know the English-speaking provinces better through my graduate work as a visiting Ph.D. student in Dr. Hallett’s lab in Guelph. Although many Canadians, especially those from nearby Toronto, describe Guelph as being a “small farm town,” it felt like a real city, especially coming from Vermont. I fell in love with Guelph — the year-round farmers market, old stone buildings, beautiful gardens, and emphasis on local food. The large sprawling farms just outside the city were the perfect places for me to do my research on swede midge pheromone mating disruption, which required lots of space between plots and treatments. Back in Vermont, where the farmland is wedged in small valleys between mountain ranges, we just don’t have the scale of crop production that there is in Ontario.

Josée Boisclair, me, Yolanda Chen, and Thomas Heer (left to right) at IRDA this summer getting ready to transplant broccoli for mating disruption research.

Working with Dr. Hallett opened up many doors and expanded my network in Canada. Last year, my advisor and I started a collaboration with the Institut de recherche et de développement en agroenvironnement (IRDA) in St-Bruno-de-Montarville, Québec. Earlier this winter, I practiced my French and mustered up the nerve to give two extension presentations on my swede midge work to francophone farmers in Québec. I was surprised at the number of people who came up to me after my talk, appreciative that I was making an effort to communicate with them in French rather than English. They were genuinely interested in working together with my research group across the border to help strengthen our research efforts to manage swede midge.

In all the time I’ve spent in Canada (which at this point can be measured in years), I can’t think of a time when I’ve felt unwelcome. On the contrary, I am impressed with how open most Canadians are to foreigners. I hope that we can continue to work together, despite language barriers, differing political systems, and other potential challenges, to gain traction in our efforts to find solutions for swede midge and other shared invasive species in the future.

/by
, ,

Czech out research abroad ~ Foreign Perspectives

 

By Dr. Lauren Des Marteaux, Postdoctoral fellow, Biologické centrum AVČR

———

No one would describe me as having wanderlust; I am a nester, molding my surroundings for maximum comfort, convenience, and aesthetics. I loved my historic apartment, my extensive set of kitchen gadgets, and all of Canada’s familiarities (AKA Tim Horton’s everywhere, anytime). As a fresh post doc I had no idea what to expect when relocating from populous southern Ontario to a dorm room with a shared kitchen in small-town Czech Republic. Now (six months later), the only way to describe my time abroad would be overwhelmingly happy. Read more

/by
, , , , ,

Rassemblement de la recherche entomologique canadienne: Septembre 2015 – Janvier 2016

(English version here)

Cet article fait partie d’une série continue de rassemblement de la recherche entomologique canadienne (Canadian Entomology Research Roundups). Voici ce que les étudiants de cycle supérieur canadiens ont fait récemment:

De la part des auteurs:

Finn Hamilton (University of Victoria)

C’est bien connu que la majorité des insectes sont hôtes à des bactéries symbiotiques qui ont de profondes conséquences sur la biologie de l’hôte. Dans certains cas, ces symbioses peuvent protéger l’hôte contre de virulents parasites et pathogens, même si dans la plupart des cas planent encore un mystère sur la façon dont les symbionts réussissent à atteindre cette défense. Dans cet article, nous avons démontré qu’une souche de la bactérie Spiroplasma qui protège son hôte drosophile contre un nématode parasitaire virulent encode une toxine sous forme de protéine. Cette toxine semble attaquer l’hôte du nématode durant une défense induite par Spiroplasma. Ceci représente, à ce jour, une des démonstrations les plus claires des mécanismes sous-jacents de la symbiose promouvant la défense des insectes. Lien vers l’article

Drosophila

Voici une mouche Drosophila falleni infecté par le nematode, Howardula aoronymphium, dont Spiroplasma  la protège. Crédit phot: Finn Hamilton.

Lucas Roscoe (University of Toronto)

L’agrile du frêne (Agrilus planipennis Fairmaire) est un buprestide ravageur s’attaquant aux frênes d’Amérique du Nord. Dans l’optique du développement de plans de gestion à long-terme de l’agrile du frêne, plusieurs projets détaillant la biologie et l’écologie de parasitoïdes indigènes peu étudiés auparavant ont été amorcés. Un des projets s’intéresse à la séquence de reproduction d’un parasitoïde, Phasgonophora sulcata Westwood. Plusieurs insectes entreprennent des actions répétées avant la reproduction qui sont souvent induites par des phéromones. Les résultats de cette étude sont la description de la séquence de reproduction de P. sulcata et la preuve que les phéromones produites par les femelles sont à la base de ses actions. Liens vers l’article

sulcata

Phasgonophora sulcata, un parasitoïde important de l’agrile du frêne. Crédit photo: Lucas Roscoe.

Marla Schwarzfeld (University of Alberta)

Les guêpes parasitiques du genre Ophion (Hymenoptera: Ichneumonidae) sont presqu’entièrement inconnu dans la région Néarctique, où la majorité des espèces ne sont pas décrites. Dans cette étude, nous publions la première phylogénie moléculaire de ce genre, basé sur les régions COI, ITS2, and 28S. Bien que nous mettions l’accent sur les spécimens Néarctique, nous avons aussi inclus des représentants des espèces les plus connus de de l’ouest de la région Paléarctique et plusieurs séquences d’autre régions géographiques. Nous avons délimités 13 groupes d’espèces, la plupart étant reconnu pour la première fois dans cette étude. Cette phylogénie nous fournit un cadre essentiel qui pourra, nous espérons, inspirer les taxonomistes à divisier et conquérir (et décrire!) de nouvelles espèces dans ce genre qui présente de grands défis morphologiques. Liens vers l’article

Ophion

A parasitoid wasp in the genus Ophion. Photo credit: Andrea Jackson

Seung-Il Lee (University of Alberta)

Seung-Il Lee et ses collègues (University of Alberta) ont trouvé que de larges territoires de rétention (> 3.33 ha) minimisent “l’effet de bordure” négatif sur les coléoptères saproxyliques dans les peuplements boréals d’épinette blanche. Liens vers l’article  Billet de blogue (EN)

beetle

Un coléoptère saproxylique, Peltis fraterna. Crédit photo: Seung-Il Lee.

Paul Abram (Université de Montréal)

La relation entre la taille des insectes et certains traits distinctifs (tel que la longévité, la fécondité, …) a été largement étudié, mais l’effet additionnel de la taille sur les traits comportementales sont moins bien connus. En utilisant le parasitoïde d’oeuf  Telenomus podisi Ashmead (Hymenoptera: Platygastridae) et trois de ses hôtes punaises comme système modèle, nous avons démontrés que la différence de taille était associé a un changement dans la plusieurs traits distinctifs (longévité, masse d’oeufs, taille des oeufs), mais aussi de certains traits comportementales (vitesse de marche, taux d’oviposition, taux de marquage des oeufs). Nos résultats mettent en relief comment la phénotype complet (comportement et traits distinctifs) doivent être considéré quand nous évaluons l’association entre la taille et la condition physique. Liens vers l’article

Telenomus

Le parasitoïde Telenomus podisi parasitisant les oeufs de la punaise Podisus maculiventris. Crédit photo: Leslie Abram.

Delyle Polet (University of Alberta)

Les ailes de insectes ont souvent des éléments directionnels rugueux – comme des poils et des écailles- qui perdent des gouttes d’eau dans le sens des éléments, mais pourquoi ces éléments ne pointent pas toujours dans la même direction? Nous avons proposé que trois stratégies sont en jeu. Les gouttes pourrait être (1) évacuer loin du corps, (2) être perdues aussi vite que possible et (3) évacuer de “vallées” formés entre les veines des ailes. Un modèle mathématique combinant trois de ces stratégies concorde avec l’orientation des poils sur un taon (Penthetria heteroptera) assez bien et pourrait être appliqué à d’autres espèces ou à des matériaux inspirés par la biologie. Liens vers l’article

Winghairs

Poils sur l’aile d’un taon (Penthetria heteroptera). Crédit photo: Delyle Polet.

Résumés bref de recherche

Taxonomie, Systématique, and Morphologie

Thomas Onuferko du laboratoire Packer à York University et ses collègues ont réalisé un vaste étude sur les espèces d’abeilles dans la région de Niagara, Ontario. Onuferko et al. ont collecté plus de 50 000 abeilles et ont découvert 30 espèces qui n’avait pas été rapporté dans la région. Liens vers l’article

Christine Barrie et ses collègues ont signalé que des mouches de la famille Chloropidae sont associés aux phragmites au Canada. Lien vers l’article

Comportment et écologie

Blake Anderson (McMaster University) et ses collègues ont étudié l’hypothèse du découplage du comportement social et de l’activité dans les mouches larvaires et adultes. Lien vers l’article

Susan Anthony du laboratoire Sinclair à Western University, ainsi que Chris Buddle (McGill University), ont déterminé que le pseudoscorpion de Béringie peut tolérer tant les basses températures et l’immersion. Lien vers l’article

Une étude par Fanny Maure (Université de Montréal) démontre que le status nutritionnel d’un hôte, la coccinelle maculée (Coleomegilla maculata), influence le destin de l’hôte et condition physique du parasitoïde. Lien vers l’article

Est-ce que la connectivité est la clé? Des laboratoires Buddles et Bennet à l’Université McGill et du laboratoire James à l’Université de Montréal, Dorothy Maguire (Université McGill) et ses collègues ont utilisé la connectivité du paysage et les insectes herbivores pour proposer un cadre pour examiner les compromis associés aux services ecosystèmiques. Lien vers l’article

 Alvaro Fuentealba (Université Laval) et ses collègues ont découvert que différentes espèces d’arbres hôtes montrent des variations à la résistance naturelle à la tordeuse du bourgeon de l’épinette. Lien vers l’article

Gestion des insectes ravageurs

Rachel Rix (Dalhousie University) et al. ont observé qu’un stress modéré induit par l’insecticide pour augmenter la reproduction et aider les pucerons a mieux se débrouiller avec le stress subséquent. Lien vers l’article

Lindsey Goudis (University of Guelph) et ses collègues ont découvert que la meilleure façon de contrôler Striacosta albicota (Smith) est d’appliquer de la lamba-cyhalothrine de la chlorantraniprole 4 à 18 jours après l’éclosion de 50% des oeufs. Lien vers l’article

Matthew Nunn (Acadia University) et ses collègues ont documenté la diversité et densité d’importantes espèces ravageuses des bleuets sauvages en Nouvelle-Écosse. Lien vers l’article

Physiologie et génétique

Est-ce que l’heterozygositie améliore la symétrie de Xeromelissa rozeni?  Margarita Miklasevskaja (York University) et ses collègues ont testé cette hypothèse dans leur plus récent article. Lien vers l’article

Xeromelissa

Un male Xeromelissa rozeni. Crédit photo: Margarita Miklasevskaja.

Jasmine Janes, récemment graduée de University of Alberta, et d’autres ont exploré les systèmes de reproduction et de structure génétique à petite échelle pour la gestion efficace du Dendroctone du pin ponderosa. Lien vers l’article

Du laboratoire Sperling à University of Alberta, Julian Dupuis et Felix Sperling ont examiné l’interaction complexe de l’hybridation et de la spéciation. Ils ont caractérisé le potentiel d’hybridation dans un groupe de Papilonidae. Lien vers l’article

Marina Defferrari (University of Toronto) et ses collègues ont identifié un nouveau peptide similair à l’insuline dans Rhodnius prolixus. Ses peptides sont impliqués dans l’homéostasie métaboliques des lipides et carbohydrates. Lien vers l’article

Techniques

Crystal Ernst (McGill University) et ses collègues ont collecté des coléoptères et des araignées dans différents habitats du Nord. Ils ont trouvé que la diversité des coléoptères et des araignées par habitat et type de trappes. Lien vers l’article

Nous continuous à aider à divulguer les publications des étudiants de cycle supérieur à la plus vaste communauté entomologique grâce aux rassemblement de recherche. Si vous avez publié un article récemment et souhaitez le divulguer, envoyez-nous un email à entsoccan.students@gmail.com.  Vous pouvez aussi nous envoyer des photos et une courte description de votre recherche dans le but apparaître dans notre prochain rassemblement de recherche.

Pour des mises à jour régulières sur la nouvelle recherche entomologique canadienne, vous pouvez joindre la page Facebook de ESC Students ou nous suivre sur Twitter @esc_students (EN) ou @esc_students_fr (FR).

/1 Comment/by
, ,

Entomologist Survey: Life & Living in Academia

This is a guest post by Dr. Laurel Haavik, post-doctoral researcher in the Department of Entomology at The Ohio State University.

—-

I am a post-doc. I’ve been one for nearly six years. Like many other post-docs, I have been working for over a decade towards my goal: a tenure-track position at a research-intensive academic institution. I enjoy research and teaching, and so a career including both seemed like a logical pursuit. I must be good enough to succeed in this pursuit, otherwise someone would have told me to opt for a different path by now. After all, only a small percentage of Ph.D.s actually become professors. I must be pretty close to achieving this goal, because lately I’ve had several interviews – no offers yet. By now, most of my peers have secured permanent positions, although some have gone on different paths. It must be my turn soon. I had faith in the system; confidence in myself.

Earlier this summer, I was invited to give a talk at a conference, in a session on women in science. I accepted willingly; the subject seemed challenging and relevant. As I began to prepare, I realized I knew nothing about it. So, I did what any scientist would do: I turned to the primary literature on women in science. What I found changed my whole perspective on academia, my career, and most importantly: my life.

I learned that the tenure system is outdated, and filters out many creative and talented people. It was established ca. 1940, when those entering academic careers were mostly men. Assistant professors were expected to live on campus, and work intensively, around-the-clock, on establishing themselves until achieving tenure. Sounds a lot like graduate school, or a post-doc, doesn’t it? There’s not much room in that scenario for having a life outside of this pursuit. It turns out that not much has changed about this in the intervening 70+ years. To make it worse, there are now few jobs and too many of us with graduate degrees competing to fill them. It turns out that women, more often than men, are willing to forgo their academic dreams because of this ridiculousness, in favor of something better – probably a happier life. It seems that there are two issues. One: is it even possible? Women are confronted with the complications of basic biology at the very same time as they would be embarking on a demanding academic career. Most of us are well into our thirties, near the end of our child-bearing years, by the time we’re on the job search. Two: they’re exhausted, wondering if an academic career is akin to never-ending graduate school. In the academic atmosphere, there is intense pressure to do more; for example, publish or perish, fund or famish. Talent and creativity that science badly needs is undoubtedly lost as women and men continue to opt out of this outdated system, and for very reasonable grounds.

I took a long, hard look at my career so far. I’m on my third post-doc. I’ve had two failed relationships and a third that might not make it if I have to move again. I’m not married. I don’t have children. I’m in my mid-thirties, meaning that if I want to have children, I better get situated and do it soon. Maybe academia isn’t for me after all, even though my interests, teaching and research, are so well-aligned with the academic mission. I realized that my adult life so far, 90% career and 10% life outside of work, is a direct product of what I like to call our broken academic system. We need to better understand and voice our discontent with the broken academic system, or it won’t change.

I wondered if others feel the same way. In my field, had others thought of leaving science? And if so, why? Has the disparity in numbers of women and men graduates vs. those occupying professional positions actually changed in recent decades? Most importantly, what allows people to cope with such a rigorous career? I’ve been lucky to have had some great mentors, support from my family, and support and encouragement from the scientific community in my field. Have others had the same kinds of emotional support systems?

My study pursues these questions among three related fields: Forestry, Entomology, and Forest Entomology. In all three of these fields women are not historically well-represented, but this has changed in recent years, especially in Entomology. There are still few women in Forestry. Forest Entomology is a small field with a very inter-connected community, which I hope will provide an interesting contrast to its two larger, sister fields.

Please follow the link below to participate in my study, by completing my survey.

I invite men and women at all stages in their careers, as well as those who are no longer in science, to participate. Please forward this invitation to anyone you know who is no longer in science, but completed graduate school (M.S. or Ph.D.). The results of this study will be published in the primary literature.

Please follow the link below to complete the brief, 28-question survey by September 30, 2015

https://www.surveymonkey.com/r/forestry-entomology

It may take 10-15 minutes to complete. I apologize for any cross-posting of this survey. No personal identifying information will be collected as part of the survey, and your participation will be completely anonymous. Answering questions in the survey will indicate consent. Participation is voluntary and you may withdraw at any time without penalty, and there are no incentives to participate. Participation will have no effect upon your relationship with the Entomological Society of Canada. This study has been determined Exempt from IRB review.

Please contact me if I can provide any additional information regarding the aims of or your participation in the survey (Laurel Haavik, 479-422-4997, haavik.1@osu.edu). For questions about your rights as a participant in this study or to discuss other study-related concerns or complaints with someone who is not part of the research team, you may contact Ms. Sandra Meadows in the Office of Responsible Research Practices at 1-800-678-6251 or hsconcerns@osu.edu.

/by
, , , ,

Tropical fieldwork in France: the Nouragues station in French Guiana

By Sean McCann, PhD Canidate in Biological Sciences at Simon Fraser University

9/10 ant-mimicking mantids recommend tropical fieldwork for prevention of insect withdrawal. (Photo: S. McCann)

9/10 ant-mimicking mantids recommend tropical fieldwork for prevention of insect withdrawal. (Photo: S. McCann)

At this stage of the long dark Canadian winter, thoughts of tropical fieldwork should be going through the heads of all sensible entomologists…If you find yourself longing for the moist and insect-filled paradise of the Neotropics, or even if that is what your research plans call for, let me introduce you to the wonders of French Guiana.

Topography near the Inselberg Camp. (Photo: S. McCann)

Topography near the Inselberg Camp. (Photo: S. McCann)

French Guiana is situated just north of Brazil on the Atlantic coast of South America, and remains to this day an overseas Department of France.  Both French and Creole are spoken, so Canadians should feel right at home.

French Guiana truly shines as a biodiversity and natural areas hotspot because unlike many countries in the Amazonian forest region, it has not experienced extensive deforestation. The immense expanses of unlogged rainforest are truly impressive.

The Inselberg des Nourages on a clear day. View not guaranteed, depends on the season. (Photo: S. McCann)

The Inselberg des Nourages on a clear day. View not guaranteed, depends on the season. (Photo: S. McCann)

There is quite active citizen science in Guyane as well, of particular interest is the SEAG, or Société Entomologique Antilles Guyane: http://insectafgseag.myspecies.info/. This society has conducted numerous expeditions focused on collection and identification of many insect taxa, and represents a great resource of local knowledge of the insect fauna.

Finding a cryptic owlfly nymph is always a nice surprise (unless you are a cricket) (Photo: S. McCann)

Finding a cryptic owlfly nymph is always a nice surprise (unless you are a cricket) (Photo: S. McCann)

I have done all my tropical fieldwork at the Nouragues station, supported by an annual grant program that seeks to assist visiting scientists with the travel and logistical expenses involved with a tropical field season. My work has centred on a bird which is a specialist predator of social wasps, the Red-throated Caracara.

Red-throated Caracaras are specialist predators of social wasps, and a common resident of the Nouragues Reserve. (Photo: S. McCann)

Red-throated Caracaras are specialist predators of social wasps, and a common resident of the Nouragues Reserve. (Photo: S. McCann)

The 1000 km 2 Nouragues reserve is located approximately 100 km SSW of Cayenne, and was established in 1995 to be both a refuge free of development and to facilitate research on Neotropical forest dynamics.

Army ants (Eciton spp.) are one of the wonders of the Neotropical raindforests. Go. See. Them. (Photo: S. McCann)

Army ants (Eciton spp.) are one of the wonders of the Neotropical raindforests. Go. See. Them. (Photo: S. McCann)

There are two research camps, the Inselberg Camp, situated just beneath a 420 m granite mountain, the Inselberg des Nouragues, and the camp at Saut Pararé, situated just below a series of high rapids on the Arataye River. The camps are accessible by helicopter, or you can take a motorized canoe (pirogue) to the Saut Pararé camp.  Both camps are administered by the CNRS (Centre Nationale de Recherche Scientifique) which has an office in Cayenne. Field costs are €20/day for students and postdocs and €35 per day for established researchers. Travel to the station can be expensive, but sharing the cost of helicopters/pirogues with other researchers can bring the costs down considerably.

Access to various parts of the forest is facilitated by an extensive trail system . Data on tree species and flowering/fruiting phenology in two large research plots at the Inselberg Camp are available. At the Pararé camp, there are also many trails, although not as extensive as at the Inselberg camp, as well as access to riverine and palm swamp habitats. Lists of species of birds, bats, fish and trees are available, and there is an impressive list of scientific data already published:  http://www.nouragues.cnrs.fr/F-publications.html.

SM7

UV lamps attract a nice variety of insects. These are particularly fabulous. Start your collection today! (Photo: S. McCann)

The camps are comfortable, with covered shelters (carbets) for sleeping and eating, and there is electricity and running water at each station (it is the rainforest!). There is also a satellite internet connection which is adequate for email and keeping in touch with labs and colleagues. Food is provided, and is quite good (as one might expect at a French field station!), cooking/cleaning duties are shared.

The kitchen carbet by moonlight. (Photo: S. McCann)

The kitchen carbet by moonlight. (Photo: S. McCann)

If you are a student or a researcher at the planning or pre-planning stages of a Neotropical research program, there is no better time than now to submit a research proposal to the scientific committee of the station. The recently announced call for proposals will fund projects to a maximum of €9000, which would nicely cover the transportation and field costs for a several-month expedition. The deadline is Feb. 14, 2013. For more information, the details are available here: http://www.nouragues.cnrs.fr/indexenglish.html

/2 Comments/by
, , ,

Here be giants. How do they breathe?

By Brent Sinclair, University of Western Ontario
_______________________________

I’m currently on sabbatical in the Department of Zoology, University of Otago in Dunedin New Zealand.  This is the department where I did my PhD, so it is an opportunity to come back to familiar territory and re-connect with all sorts of people and places from the past.  It’s not a very insect department, but there is a lot of interesting work on ecology, parasites and freshwater biology.  A sabbatical is all about recharging scientific and creative batteries, so my main goal here is to write and read and think (and drink coffee and run and hike – but that’s for a different blog), but I felt that I also needed to justify coming all this way by actually gathering some data while I’m here.  Respirometry is the perfect answer – once set up, it’s possible to gather data on metabolic rates, breathing patterns and water loss at the expense of only a few minutes at each end of a run, leaving plenty of space for writing and drinking New Zealand’s excellent coffee in between.

What is respirometry?

Respirometry is the science (art?) of measuring the products and substrates of respiration – depending on your strategy, you can measure oxygen consumption and/or carbon dioxide production (to get a handle on metabolic rate) and water loss – among other things.  Because I work on generally small insects at generally low temperatures, we mainly measure carbon dioxide production and water loss (the instruments are much more sensitive), and can do some clever calculations to turn this into estimates of metabolic rate.

The equipment itself can look quite intimidating – and certainly like Science – with plenty of tubes and wires (when I calibrate the water channel, there’s even a bubbling flask!), but it’s not that difficult once you figure out what everything is doing, and it looks scary enough that other people generally don’t mess with it.  We pass CO2-free, dry air over an insect, and measure the CO2 and water vapour in the excurrent air – all the CO2 and water vapour must have come from the insect, so we can calculate how much it is breathing out.  The equipment we use is from a company in Las Vegas called Sable Systems International.  Sable Systems’ head honcho, John Lighton, is an insect physiologist who has published in places like Nature and PNAS, which means that when he designs the equipment, he often has insects in mind.

The respirometry system set up in a controlled-temperature room at the University of Otago. CO2-free dry air is supplied by the gas cylinder, and passes through a chamber containing the insect housed in a temperature-controlled chamber (the big grey cooler box), before going on to an infra-red gas analyser (the green box), which uses IR absorbance to measure CO2 and H2O.

What else can we learn from respirometry?

As well as a simple measure of metabolism, it is possible to use respirometry to determine the thermal sensitivity of metabolism (this is important in understanding the effects of climate change), as well as the metabolic costs of various environmental stresses, like freezing or chilling.  We can also use respirometry to study how insects breathe (there is much debate surrounding the adaptive significance of the Discontinuous Gas Exchange Cycles observed in some insects), and we can also use respirometry to figure out how much water is being lost across the cuticle of insects – even small ones like individual flies!

What am I …er… respirometing?

After 65 million years of evolution without mammals, New Zealand has an amazing array of endemism and some pretty weird insects.  My favourites are the alpine insects, which include impressive radiations of cockroaches, stick insects and weta – large Orthoptera related to the Jerusalem crickets of North America.  The mountains are fairly young (<3 million years old), so it’s possible to do all sorts of work comparing alpine species with their lowland relatives .

A group of alpine weta, Hemideina maori found under a stone at 1400 m a.s.l. on the Rock and Pillar Range, Central Otago, New Zealand. The males defend harems of 2-7 females. Female weta can weigh over 5 g, and males over 7 g, making them the heaviest insect known to survive internal ice formation. Photo by B. Sinclair.

Of course, it is the most fun to work on the big, weird insects.  So far I’ve been putting alpine weta (Hemideina maori, Orthoptera: Anostostomatidae) and New Zealand’s longest insect, the gloriously-named phasmid  Argosarchus horridus through their paces.  Male alpine weta can weigh up to 7 g, and are the largest insect species known to withstand internal ice formation.  The stick insects can easily reach 4 g, and posed some unique challenges in respirometry – with a body form so long and stick-like, it makes perfect sense to use a converted spaghetti-storage container!

A large female Argosarchus horridus (this one weighs a shade over 3 g) ready to go in her respirometry chamber. Photo by B. Sinclair.

The main questions I will be addressing will be about the evolution of thermal sensitivity and water loss in alpine insects, but the great thing about respirometry is that I never know what I’ll find along the way!

_____________________________________________________________

Brent Sinclair is an Associate Professor at the University of Western Ontario.  He is the 2012 recipient of the Entomological Society of Canada’s C. Gordon Hewitt Award.

/by
, , ,

Luminous impressions of nocturnal pollinator research

By Paul Manning, B.Sc. student at Nova Scotia Agricultural College
_______________
As an undergraduate student, I’ve been working diligently on the final hurrah of my four year career; the undergraduate thesis. I’ve been fortunate to work under the supervision of Dr. Chris Cutler for the past two summers, learning about the ecology and roles of insects within wild blueberry production. Though I’ve worked on a wide variety of projects within the lab, I’ve realized quickly that pollination was the aspect of entomology that I found to be particularly intriguing.

Blossoms of wild blueberry May, 23rd, 2012 (Photo by P. Manning)

One of the projects that caught my eye was as a continuation of a trial that our lab did in the summer of 2011. By sanctioning off areas of wild blueberries with cages that prevented pollinators from accessing the flowers, the team discovered that approximately a third of pollination events may be attributed to nocturnal insect activity, as well as weight of ripe berries being insignificant between nocturnal, and diurnal pollinated treatments.  Though a number of insects were collected using Malaise traps in this study, it was not possible to conclude captured insects were responsible for vectoring the pollen.

Lo and behold, there was a great opportunity for my thesis; to discover the identities of nocturnal pollinators within wild blueberry production. Armed with a sweep net, kill jars, a mercury-vapour lamp, tissue and enough ethyl-acetate to open my own nail salon we began to hit the field. Our sampling periods happened at two different times during the night; an early shift that started as soon as the sun went down, and a shift that started at 12:00 AM. Each sampling session lasted for two hours in length.

We implemented an interesting capture method, which worked extremely effectively. Under the glow of the mercury-vapor lamp, we placed a large 8×4 plywood board against the fence, making an 80° angle with the ground. When the insect landed upon the board, a quick capture could be made by placing the kill-jar against the board, and giving the board a small tap. This caused the insect to fly up into the kill-jar.

Screen illuminated by the mercury-vapour lamp (Photo by P. Manning)

June beetle captured with light trapping (Photo by P. Manning)

As the mercury vapor lamp began to buzz, insects began to make their way out of the dark and against our screen. The diversity was stunningly interesting, quite surprising. Tiny midges, large scarab beetles, hawk moths, and nocturnal icheumonids were included amongst our varied group of visitors.

[youtube=http://www.youtube.com/watch?v=OJNKIzoC-yE]

Sweep samples were also taken in an area of darkness within the field. We used ethyl-acetate fumigated from a ventilated jar, within a larger Tupperware container to effectively kill the insects without struggle. The diversity from these samples was very different; being attributed mostly to beetles and small flies.

Insects were analyzed to find whether or not they carried pollen using methods. By swabbing the eyes, head, and mouthparts with a small cube of fuchsin gel.  By sealing these slides with the aid of a Bunsen burner, blueberry pollen was easily detected through its distinctive tetrad shape using a light microscope.

As the samples have been analyzed, the diversity of insects that may represent the nocturnal pollinators of wild blueberry is staggering. Though the work has been challenging and sometimes very tedious (have you ever attempted removing pollen off the head of a thrips?). I’ve learned a great diversity of things, including: an incredibly simple way to differentiate between icheumonids and brachonids; that there are an incredible number of fly families that vaguely-resemble a typical housefly; and that iced-cappuccinos do contain caffeine (after finally drifting off to sleep at 4:30 AM on a Sunday morning).

A small moth visits the light screen after sampling finishes (Photo by P. Manning)

This project has been a great way to open my eyes to the diversity of insects responsible for ecological functions. When prompted with the cue ‘pollination’ – my mind has been switched over from the typical image of a honey-bee – to a myriad of insect visitors among flowers. This is a vision of pollination which to me is something more; diverse, representative, and inclusive of this invaluable ecological service.

_____
References:

Beattie, A. J. 1971. A technique for the study of insect-borne pollen. Pan-Pacific Entomologist 47:82.
Cutler, C. G., Reeh, K. W., Sproule, J. M., & Ramanaidu, K. (July 01, 2012). Berry unexpected: Nocturnal pollination of lowbush blueberry. Canadian Journal of Plant Science, 92, 4, 707-711.

/2 Comments/by
, ,

Stupidity is the mother of invention

By Dr. Terry Wheeler, Director of the Lyman Entomological Museum, McGill University

_________________________________

Warning: the following post contains content that makes a university professor and museum director look a bit ridiculous. Readers who wish to cling to the fiction that University Professors are smart, infallible and wise may find this post unsettling.

“Do you have everything?” A logical and reasonable question from The Students as The Professor exits his hotel room in the morning, several bags in hand. Some Students may consider such a question presumptuous, but it’s good to run through these little mental checklists.

Lesson #1 (for Students and Assistants): “Do you have everything?” may be a little too broad a question. A series of questions identifying particular individual items of necessary field equipment might be better. In this case, for example, a question along the lines of “Do you have the sweep net handles?” might have saved much subsequent humiliation and hilarity.

Lesson #2 (for Professors): Pack the gear the night before AND get enough sleep!

We jumped in The Vehicle and headed south for a long day of collecting in the dry prairies of southeastern Alberta. We had our sights set on a few promising collecting spots and it was a sunny day. After an hour or so of driving we arrived at the first site and The Professor disgorged the contents of the several bags as The Students waited to begin doing science. “Where are the net handles?” asked both Students, almost simultaneously. “Well,” replied The Professor “obviously they’re in the $#%#$ hotel in my &#@% red duffel bag.”

Lesson #3 (for Students and Assistants): Do not be afraid to laugh at a Professor, especially when they deserve it.

Lesson #4 (for Professors and Aspiring Professors): You can’t afford to take yourself too seriously. Things happen and people will laugh at you. Pretend you’ve just told a wickedly funny joke. I find that helps.

So, not relishing a long drive back to the hotel in the prairie heat, The Professor was forced to improvise, which he did in a rather unspectacular way, and the Short-Handled Shortgrass-Prairie Sweep Net (SHSPSN) was born.

The short-handled shortgrass-prairie sweep-net, ready for deployment. (Photo by T. Wheeler)

Some readers will recognize the SHSPSN as reminiscent of a short-handled folding insect net commonly referred to as a “National Park Special”, a net that folds up compactly and is easily concealed in a pocket for . . . well . . . ummm . . . inclement weather and increased mobility and the like. In our case (we were not in a National Park or other similarly protected area), the short handle worked quite well to keep us low and out of the high wind blowing across the site. Of course, the actual process of sweeping required a slightly modified stance compared to regular sweeping.

Anna demonstrating excellent SHSPSN technique. Her back will be fine. (Photo by T. Wheeler)

In the end, we collected (very successfully!) at four good sites that day with our lightweight, compact SHSPSN’s. Fortunately, we encountered no other Entomologists (especially Lepidopterists, with their penchant for freakishly long-handled nets) who could have taken advantage of our predicament and heaped ridicule upon us, especially The Professor.

And the next morning, when The Professor emerged from his room, well-rested and laden with several bags, The Students greeted him with a hearty “Do you have the net handles?” and it didn’t sound sarcastic AT ALL.

Lesson #5 (for Students and Assistants): Sooner or later, every Professor is going to do something dumb. Take joy in such magical moments. They are the times that make The Professor appear slightly less than superhuman. It helps to have a camera handy for the more spectacular times. Such photos make great content for retirement celebrations or department Christmas parties.

Lesson #6 (for Professors): The great thing about tenure is that you can actually get away with a lot of really dumb stuff. Just don’t lose any Students in the field – there’s a lot of paperwork involved. I find keeping the numbers low and giving each of them a distinct name helps. Take attendance a lot. Especially at airports.

And if anyone would like plans for making their very own SHSPSN, please contact The Professor.

_________________________

The original post can be found on Dr. Wheeler’s blog, here: http://lymanmuseum.wordpress.com/2012/07/23/stupidity-is-the-mother-of-invention/

We’d love to hear about other people’s (mis-)adventures in the field! Please feel free to send your stories and pictures to EntSocCanada@gmail.com

/2 Comments/by
, ,

Cool Insect Viruses

By Michel Cusson, ESC President
______________________________

For my first blog post, you’d probably expect me to talk about some hot issue pertaining to the ESC. However, I chose otherwise (at least this time) and I’ll save Society-related topics for my “Up Front” column, which you can read in the online version of the Bulletin. Instead, I’d like to introduce you to what I consider the coolest product of insect evolution: the use of symbiotic viruses by parasitic wasps to manipulate the physiology of their caterpillar hosts.

Aleiodes indiscretus wasp parasitizing a gypsy moth caterpillar. Photo by Scott Bauer.

In an unusual twist of evolutionary history, some ichneumonid and braconid parasitoids have “captured” a conventional virus and “domesticated” it so that it can be used to their own advantage in the course of parasitism. The viruses in question, known as polydnaviruses (from poly-DNA-virus, but typically pronounced “polyd-na-virus”), replicate in wasp ovaries where they accumulate in the fluid bathing the eggs, before being injected into the caterpillar during parasitization (egg laying). While the carrier wasp is completely asymptomatic, the infected caterpillar displays AIDS-like symptoms, whereby its ability to mount an immune response against the wasp egg or larva is depressed by the virus. In addition, the virus will often block host metamorphosis, particularly when parasitization takes place late in caterpillar development; this will allow the wasp larva to complete its own development before the host undergoes the traumatic events associated with the larva-to-adult transformation.

But what makes these viruses pathogenic in the caterpillar while being apparently harmless in the wasp, and how could such unusual creatures have evolved? To begin understanding the answers to these questions one first needs to know that polydnavirus genomes are permanently integrated into the chromosomal DNA of the carrier wasps. This means that all individuals within a species known to carry one of these viruses contain the viral DNA within their own genome. Production of the viral particles, however, is confined to females and occurs only in ovaries. There, copies of the integrated form of the viral genome are synthesized and packaged into a proteinacious coat known as the “capsid”. These viral particles are released into the lumen of the oviduct, where they accumulate until injection into the caterpillar host.

What’s going on “behind the scenes”. Image by Michel Cusson and Marlene Laforge.

Once injected, the virus gains access to various host tissues where some of its genes are expressed, leading to the synthesis of viral proteins that do the dirty work, i.e., depress the host immune response and perturb host development. Few, if any, of these virulence genes are expressed in the wasp, which probably explains why the wasp is asymptomatic. While the virus does not replicate in the caterpillar, it is the expression of viral genes that makes it possible for the wasp egg and larva to survive within the host. And successful development of the immature wasp is what ensures transmission of the integrated form of the virus to the next wasp generation.

Whether polydnaviruses are “real” viruses has been a matter of debate for many years. For example, some have argued that, although they look like viruses, they are nothing more than a smart device that the wasps have evolved to transfer host-regulating factors to caterpillars during oviposition. However, it is becoming increasingly clear that polydnaviruses arose from ‘conventional’ viruses.

Recently, a group from France has shown that the proteins that make up the coat of braconid polydnavirus particles are highly similar to those of ‘nudiviruses’1, a group of conventional insect viruses that are capable of integrating their genomes into those of their hosts. So, it appears that the genome of a nudivirus became permanently integrated into the chromosomal DNA of an ancestral braconid, some 100 MYA. Since then, evolution has led to the replacement of the original nudiviral virulence genes by other genes that are usefull to the wasp during parasitism. The wasps may therefore be viewed as having ‘domesticated’ the nudivirus, turning it into a mutualistic virus – a phenomenon fairly unique in the world of viruses. Cool stuff, isn’t it?

____________________________
This post was chosen as an Editor's Selection for ResearchBlogging.org1Bezier, A., Annaheim, M., Herbiniere, J., Wetterwald, C., Gyapay, G., Bernard-Samain, S., Wincker, P., Roditi, I., Heller, M., Belghazi, M. & (2009). Polydnaviruses of Braconid Wasps Derive from an Ancestral Nudivirus, Science, 323 (5916) 930. DOI: 10.1126/science.1166788

/5 Comments/by