Leading a discussion of a scientific paper

I’m teaching a graduate class in Entomology this term, and part of that class involves students leading discussions about scientific papers in our discipline. These discussions are typically between 60 and 90 minutes, with a small group (4-6 individuals). This post provides some advice and guidelines around how to go about doing this. That being said, this is not a ‘one size fits all’ kind of world, especially when talking about science: you may have better or alternative approaches when discussing scientific papers – please comment, and share your ideas!

1. Provide a (quick) summary of the paper:

In most cases, you want to first provide the audience a brief but accurate overview of the paper. It’s often useful to do a little research about the authors – this provides a context that may be very helpful and may prove insightful later on. For example, do the authors have a publication record that aligns with the current paper? Are the authors graduate students or post-doc (not that it matters, but it does provide context!).

The focus on the summary should be about the Research Questions / Hypothesis, and to explain these you will also need to discuss an overall conceptual framework. This means you need to know this conceptual framework very well. After providing the broader context and framework, you should quickly go over the main methods, and the key results. You should act as a guide for your audience, and take them through the key results. Try not to spend a lot of time on more trivial aspects of a paper. In general, your summary should not delve too deeply in the discussion part of the paper.

Don’t forget: you are assuming everyone in the room has read the paper, so your overall introduction should be relatively short (no more than 10 minutes). More time may be required if a concept or methodological approach is particularly complex. Try not to provide opinions or critiques of the paper at this point in time – save this for the general discussion.

2. Ask for points of clarification:

Before proceeding with detailed discussion of the paper, you should ask the audience if they require clarification on anything in the paper. You are leading a discussion and therefore considered an ‘expert’ on the paper, and as such, should be prepared to handle these points of clarification – this will most likely require you to do a bit of research on areas of the paper that you do not understand!  It’s important you you make it clear that you are not starting a detailed critique (yet); you are first making sure that people all understand the critical ‘nuts and bolts’ of the paper.

3. Leading a discussion:

The majority of the time should be spent on the actual discussion.  There are many ways to do this, but here are some tips:

  • Try not to let your own opinion of the paper distract or take over – your goal is to get other people to reveal their own views; these may or may not agree with your own views! Be welcoming and accommodating to other people’s opinions and viewpoints. Never make anyone feel small or stupid, even if they make a goofy mistake.
  • That being said, make sure that you do have an opinion, and be willing to share it at some point
  • Prepare a list of questions that you could ask other people if the discussion needs help to get started. Always try to find positive points in a paper, even if the paper is, overall, very weak. Similarly, try to bring out negative features even if the paper is strong.  This means you have to sort out strong and negative parts of a paper for yourself (well ahead of time)
  • It’s sometimes a good idea to first go around the room and ask for something that people felt was strong and positive about the paper, and then do this again but ask for points of constructive criticism about the paper.
  • Don’t hesitate to ask people (specifically) for their views on some sections of this paper: a gentle push may be needed to get started on discussing the specifics, but this can be fruitful.
  • Since you are chairing the discussion, don’t be afraid to take control if the discussion wanders too far from where it needs to be, and/or if the discussion gets too trivial or mired in the weeds
  • Related, whenever possible, draw the discussion back to the actual research objectives, and try to broaden the discussion out to the overarching concenptual framework: are the results generalizable to other fields? Does the paper make broad and meaningful conclusions that will be long-lived and significant?
  • Towards the end of the discussion, it may be useful to ask people how they might have done the work differently. Or, stated another way, what could have been improved?

4. Summarize the discussion:

Spend the last five minutes of your time reminding people abou the actual research objectives, and provide a concise summary of the discussion that just wrapped up. Do this in an inclusive way, and give a nod to everyone in the room: make everyone feel that their points of views and opinions are taken seriously.   Try to get an overall consensus about the general quality of the paper, and one litmus test may be whether or not you would cite the paper in your own work, and in what context.

Meet the lab: Elyssa Cameron

Here’s another in the “Meet the lab” series – written by Master’s student Elyssa Cameron.

Like many in my field, my love of nature and the creatures which inhabit it began much earlier than I can remember. From camping trips to day camps to museums and everything in between, I have always been passionate about understanding the world around me. Whether I was catching butterflies, trying to identify an elusive bird, exploring a new place or simply basking the in the beauty and wonder of an unaltered landscape, I knew that I wanted to be an advocate for nature.

Elyssa

Elyssa Cameron, with a furry friend.

In 2011, this led me to pursue an undergraduate degree at McGill University in Environmental Biology, specializing in wildlife. Here I learned the skills and thought processes that would help guide me on my journey. This is also where I feel in love with ecology and ecosystem dynamics. I was humbled by the enormous web of complexity which governs our world and sought to discover where exactly my interests lay. My search took me to South Africa, where I spent 3 week learning about wildlife management, game ranching, governance of national parks, and the challenges in maintaining healthy, safe, sustainable populations and ecosystems. It was during this trip that I realised that the management and conservation of any ecosystem needed to rest upon a solid understanding of the ecology of the system as well as the interactions of individual species, between different species and between species and their environment. Without this basic knowledge of how something works, one cannot hope to protect it.

giraffe

With this newfound drive for management and conservation through a better understanding of ecosystem ecology, I signed on to do a Master’s project with Chris Buddle (McGill University) on arctic arthropods in 2014. Having never truly worked on insects and spiders before, I knew such an undertaking would be a challenge; but one that I was excited to take on! The aim of this project is to establish a more comprehensive long-term ecological monitoring program in Cambridge Bay, Nunavut, by linking patterns of vegetation and habitat diversity to arthropod diversity. In this way, we can examine the arctic ecosystem in a more complete way and not as a series of individual pieces. This will allow for more effective management in this rapidly changing ecosystem and will hopefully provide more predictive power for models and policies.

However, to obtain these baseline conditions, we must first collect the data. This took me on my second great adventure – a summer in Canada’s high arctic! For those of you who have not yet experienced the vast and diverse beauty of Canada, it is something I cannot recommend enough. But be forewarned, there are LOTS of bugs – which was great for the Bug Team! Working in association with CHARS (Canadian High Arctic Research Station) the Bug Team was part of a unit of researchers set on better understanding the arctic ecosystem and promoting interdisciplinary collaboration. We sampled spiders, flies, beetles, wasps and others to try and get the most complete view of the species diversity and community structure as we could in such a short summer.

Arctic

Elyssa’s Arctic Adventures!

While there, we also did a number of community outreach programs to try and get the locals interested in science. We participated in a science night, made insect and butterfly collections to leave at the high school and Sarah Loboda (one of my wonderful lab mates!) organized day camp activities for the kids.

Now back at McGill, I spend most of my days in the lab looking through a microscope. With the general sorting of samples now complete, I am about to embark on my biggest challenge yet: species identifications! Both scary and exciting; but with the great support system here, I’m not worried.

As of January, I will also be co-supervising an intern from the Vanier Wildlife Technicians program with Chris Cloutier (the lab’s resident mosquito expert).

Homage to the squished mosquito

This work comes from a student* in my field biology class. Part of the course includes students keeping a “field journal“, and that assignment allows an opportunity for students to express their thoughts and observations about nature in many different ways, from writing, to art, and poetry.

 

A mosquito, before the squish. (photo by Alex Wild, reproduced here with permission)

A mosquito, before the squish. (photo by Alex Wild, reproduced here with permission)

 

O squished mosquito, you omnivorous parasite,

Why could nectar not quench your hunger, like your male counterpart?

Why must you thirst for my blood?

 

Of course, you need blood for egg production,

But to what lengths will you go to continue your lineage?

Was it my personality that drew you in? Or simply my CO2 expulsion?

 

Your ultimate death has left me with no answers;

Only a bump on my skin filled with histamine and regret.

 

Your short life makes me itch to know more about who you were

…or perhaps that’s just the anticoagulant in your saliva.

 

While the swelling in my arm may decrease,

My pining for you never will.

 

R.I.P., mosquito

2014-2014

Mosquito

 

What does this poem tell me, as an instructor?

It tells me that students can express natural history and biology in many different ways.

It makes me think that the student will remember the basics of mosquito biology a lot more than had this been on a multiple choice or short-answer examination.

It shows the power of allowing emotion to find its tendrils into science. We ought to embrace this a lot more.

 

*the student shall remain nameless until after the course is finished, but will eventually be credited appropriately

Trophic cascades in fragmented forests

Many birds eat insects and spiders. Some of these insects and spider are themselves predators, feeding on critters lower down in the food web. Some of the insects that are fed upon by birds, or other predators, also play important roles in forest, such as munching upon the fresh, green leaves of young trees (here’s a reminder).

Munch, munch, munch. The hungry caterpillar. (photo by Sean McCann, reproduced here with permission)

Munch, munch, munch. The hungry caterpillar. (photo by Sean McCann, reproduced here with permission)

These interactions are ongoing, all the time, in forests around the world. These forests, however, are changing in important ways. Some of them are getting smaller and smaller as humans continue to encroach on the land, via urbanization or agriculture. This results in a ‘fragmented’ landscape. A landscape with small forest patches, perhaps no bigger than your back yard. A landscape with larger forests, perhaps one in which you could get lost in. These forests are themselves connected to each other –sometimes directly by a corridor or hedgerow.

This is the context for PhD student Dorothy Maguire’s research. Within that context, Dorothy tackled a fascinating project, one that was just recently published. In this work, Dorothy and co-authors (including me, an undergrad at that time, Thomas Nicole, and McGill Professor Elena Bennett) put cages around small trees in different types of forests SW of Montreal. The cages (made of chicken wire) were in place to test the effects of ‘predator exclusions’ on the insects and spiders occurring on saplings. The prediction is that if you exclude larger predators, such as birds, this may allow a ‘release’ of other insects and spiders. In turn, this release may have trickle-down effects on an important process occurring in young trees: herbivory. For example, if a predator is more common because it’s not being eaten by birds, perhaps it will eat more caterpillars, which may mean the leaves on trees will be eaten less frequently. In ecology this is dubbed a ‘trophic cascade’. Dorothy did this work in the context of fragmented forests, and she worked in forests that were either small and isolated from other forests, or in forests that were large and connected to other forests. This was done because there’s an expectation that these ecological effects will be different depending on the degree of fragmentation happening on the landscape. For example, insectivorous birds may decrease in abundance in small, isolated patches, which means their effects on insect prey (and perhaps herbivory) may be reduced relative to effects in larger patches of forest.

Dorothy Maguire, working in a forest fragment.

Dorothy Maguire, working in a forest fragment.

During one summer field season, Dorothy and Thomas wrapped up some small sugar maple trees in chicken wire, left some alone as controls, counted insects and spiders over the summer months, and measured herbivory on the trees themselves. As expected, the effects of the ‘cage’ was significant: when you put a cage around a tree, you end up with more arthropods living on those trees. This confirms other papers which report a similar effect: insectivorous birds (and perhaps other vertebrate predators) have a significant, and meaningful impact on the insects and spiders living on trees. Or, stated another way, birds eat critters living on trees, and without these birds, there would certainly be more arthropods around!

Dorothy did not uncover a strong effect on the process of insect herbivory: although more insects and spiders were living in the trees protected by chicken wire, the leaves themselves were not affected. This could be because more insect predators were around, and thus compensating for the lack of birds, and eating just as many herbivorious insects (e.g., caterpillars) as the birds might have eaten.

The lanscape of southern Quebec. Lots of agriculture, some patches of forest.

The lanscape of southern Quebec. Lots of agriculture, some patches of forest.

Scaling up to the landscape context, there were no overall significant effects of the cage treatments in relation to the forest type, nor was the level of herbivory dependent on the landscape context. The general results for large, connected patches were no different than for small, isolated patches. However, the magnitude of the effect was marginally affected by the landscape context for the cage exclusion: vertebrate predator may have a more significant impact in smaller, isolated patches.

As with all research projects, this work resulted with as many questions as answers, which is equally frustrating and fascinating. It’s clear that vertebrate predators are important in these systems, but more work is needed to fully assess whether these effects are truly affected by the degree of forest fragmentation on the landscape. The lack of effects on the process of herbivory itself was equally intriguing – there are clearly many complex interactions occurring on small maple trees. Some of these interactions involve top-down predation events, but there are likely a suite of ‘bottom-up’ effects that are also influencing the system.

Reference:

MAGUIRE, D. Y., NICOLE, T., BUDDLE, C. M. and BENNETT, E. M. (2014), Effect of fragmentation on predation pressure of insect herbivores in a north temperate deciduous forest ecosystem. Ecological Entomology. doi: 10.1111/een.12166

Meet the lab: Sarah Loboda

This is the second in a series of posts that will introduce the members of the arthropod ecology lab. This one is about Sarah Loboda:

I am not one of those people who can reflect back on my childhood with memories of chasing butterflies with a net. Instead, I could be found shouting loudly when seeing a spider in the bathtub. Things change… today I study community ecology of Arctic arthropods, and have a deep passion for arthropod of all kinds, from spiders to butterflies and flies.

Sarah, with a butterfly net.

Sarah, with a butterfly net.

My interest in entomology began as a challenge, and I love challenges! When I was an undergrad at Université du Québec à Rimouski, Québec, a tackled the big challenge of learning to identify insects. During my undergrad, I participated in several research projects where I could encounter biodiversity of insects and spiders and I developed a curiosity and a fascination about arthropods, particularly those living in extreme Arctic environments. Arthropods are ectotherms, yet they survive, year-round, in a region where the climate is very harsh. I quickly realized that the taxonomy was not the only interesting aspect in entomology. I wanted to identify arthropods in order to do research on community ecology. During the final year of undergrad in Rimouski, I decided to do a research project on the community ecology of spiders in salt marshes. As part of this project, I met Chris Buddle who encouraged my passion for entomology and the Arctic and I was lucky to do a Master’s project on spiders in the Canadian North as part of the Northern Biodiversity Program.

I take all opportunities to do outreach, and talk about insects and spiders with anyone who is interested. I am also involved in different societies, including the Entomological Society of Canada, and the Entomological Society of Québec, for which I’m the student representative. I love to volunteer and organize activities for members. Being the mother of two children, I also like to share my passion about arthropods with my kids, their friends and classmates in schools or daycares.

Sarah in front of her awesome poster at an Entomological Society of Canada meeting. This poster was a runner-up for a prize!

Sarah in front of her awesome poster at an Entomological Society of Canada meeting. This poster was a runner-up for a prize!

I have just started the second year of my Ph.D. I work with the veritable goldmine of data that has been collected from Zackenberg (northeast Greenland), where a long term monitoring program of arctic biodiversity has existed since 1996. My primary research objective is to assess temporal changes of the Arctic fly communities in this region, using the Muscidae and Phoridae families as model study taxa. The second objective of my research project will be to assess phenotypic and genetic changes over the last two decades in two species of Arctic muscids from Zackenberg. For this project, I am co-supervised by Jade Savage, a muscids expert from Bishop’s University, and Toke Høye from Aarhus University.

What is the motivation for pursuing graduate school?

Last week an interesting hashtag was floating around twitter:  #whyididaphd.  It was great to see reflections on this topic, and during our most recent lab meeting, I asked my students why they were pursuing advanced research-based degrees, and here are some of their responses:

  • Graduate school allows an opportunity for freedom to do the things you find interesting, every day.
  • Doing research means you can follow your interests and curiosity.
  • Doing a MSc is a perfect transition between an undergraduate degree and whatever might come next!
  • Doing research is an opportunity to work independently, and this is important to me.
  • Research is about gaining knowledge and learning on  your own. It’s like the best kind of drug: you can get hooked and it’s good for you, and it never ends.
  • Graduate school develops my network of collaborators, and I need this as I enter the work force.
  • I want to do things that are relevant, and are my ‘own’. Research allows this.
  • Doing an advanced degree was an important career stage, because I need it in order to do what I really want to do into the future (i.e., academic position).

These reflections were insightful, and showed that the students had wonderful motivations for pursing advanced degrees in a research-based laboratory. I agree that doing a MSc or PhD is perfect for people who are curiosity-driven, and who appreciate the independent nature of the work.

I had two responses to #whyididaphd. The first one certainly reflects my thinking now:

Screen Shot 2014-10-08 at 1.12.23 PM

The second response is a little more honest, and reflects my thinking at the time I decided to continue with research, about 20 years ago:

Screen Shot 2014-10-08 at 1.13.21 PM

Is it wrong to pursue a MSc or PhD “just because there’s nothing better to do”, or “because I don’t have another plan and I like University”?  We had a heated debate about this, and the lab was divided. One argument is that it’s a total waste of time, energy, money and resources to pursue a MSc or PhD “just because”. Sure it’s nice to stay in a University after the undergrad degree is done, but why pursue it unless you know you need that advanced degree!  Have a plan, have a career goal, and if a MSc or PhD is part of that plan, pursue graduate school.

In contrast, if you don’t have a plan, or a specific career in mind, perhaps graduate school is the *perfect* place to develop your research skills in an exciting, and familiar environment. Graduate school is a perfect transition to many, many careers, so if there is nothing else on your horizons, keep on trucking along at a University! If you are a curious person, and independent thinker, it’s an ideal learning environment.

I suspect many people fall somewhere in the middle (I think that was the case for me).  I always felt I might eventually like a career at a University, and since I seemed to like research, and be good at it, pursuing graduate school was a natural progression. So, even if the motivations for doing graduate school aren’t always based on a clear career path, those motivations can still be more than enough to give it a try.

I’ll finish by expanding that last point: “give it a try” does not mean “stick with it even when it’s not working”.  It’s important to know when to quit if grad school is not for you. It’s an awfully difficult and frustrating process if it’s not going well. Give it a try if it floats your boat, or it’s what you need. However, also know when to quit.

 

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Meet the lab: Crystal Ernst

This is the first in a series of posts where each Arthropod Ecology lab member can introduce themselves. First up is PhD student Crystal Ernst:

I’m a Ph.D. candidate in the final stages of my program: these days I’m crunching out analyses and writing papers as I prepare to submit my thesis at the end of the term. As a community ecologist, I spend a lot of time thinking about how and why different species assemble together in space and time. These questions are foundational to the study of ecology and provide the overall framework for my research program, which uses beetles and other ground-dwelling arthropods to study the structure and determinants of terrestrial animal assemblages.

PhD student Crystal Ernst installing pan traps along the Dempster Highway (Yukon)

PhD student Crystal Ernst installing pan traps along the Dempster Highway (Yukon)

I have spent my summers conducting field research in gorgeous, remote regions of our northern territories, including Kugluktuk Nunavut and the Dempster Highway in the Yukon. My colleagues, members of the Northern Biodiversity Program, have contributed to the collection efforts as well, resulting in specimens being obtained from twelve different locations in the boreal forest, the subarctic and high arctic, spanning Canada coast to coast. I’m now neck-deep in the joy of interpreting the stories contained in my collection of specimens.

Specimens in pan trap (photo by C Ernst)

Specimens in pan trap (photo by C Ernst)

 

Sorting specimens back in the lab

Sorting specimens back in the lab

I’ve taken two approaches with this work. First, I’ve used a fairly traditional taxonomic approach to studying these animals: by identifying them morphologically (with a microscope and identification keys), I can associate each individual with a known insect species – although some new species have also been discovered! With this information I can describe the species richness (diversity) and distributions of different beetles in the north, and see which species are associated with each other at different northern locations. Secondly, I’ve looked at my arthropods from the perspective of their ecological functions – their roles in their environments. For example, some insects are responsible for pollenating plants, others are important decomposers, and others still are predators; arthropod assemblages can therefore be described in terms of the diversity and dominance of different functional groups. I am in the process of comparing taxonomic and functional assemblages found across northern Canada, and working to determine what aspects of their ecosystems (things like: temperature, wind, and sunlight; the diversity and structure of the plant community in which they live; soil characteristics) are associated with the way these assemblages are structured, and how they change over time and across space.

Three color morphs of Blethisa catenaria, a rare subarctic species (H. Goulet)

Three color morphs of Blethisa catenaria, a rare subarctic species (H. Goulet)

A fun complementary topic I’ve researched is the relationships between some high arctic ground beetles and a fascinating group of parasites called hairworms. I found a number of beetles from different locations to be infested with these worms; in one instance almost a quarter of the beetles were infected! The parasites are aquatic as adults and must first infect an aquatic insect (like a mosquito larva) before being transmitted to a terrestrial host (like a beetle) via the predation of the aquatic host by the terrestrial insect. To complete their life cycles, the worms somehow compel the beetles to enter the water, effectively forcing them to drown themselves so that the worms can emerge safely into their aquatic habitat. This discovery suggests an important link between the creatures living in terrestrial habitats and those in aquatic habitats and tells us about the arctic food chain: beetles must be eating mosquitos or other insects that have aquatic larval/immature stages. These prey items may, in fact, be a very important source of food. More work needs to be done to confirm this! In the meantime, I am excited to have found these associations – the fact that these particular species of beetles can be hosts for hairworm parasites is new information, and it appears that the parasite itself is a new species!

Pterostichus caribou with hairworms (C. Ernst)

Pterostichus caribou with hairworms (C. Ernst)

When I’m not writing my thesis or putting obscure little black beetles on pins, you can probably find me working at McGill’s Teaching and Learning Services, enjoying my time as a teaching assistant, networking on Twitter, mucking around in my vegetable garden (or putting said veggies in jars), walking my dogs, enjoying nature while canoe tripping with my partner, poking wildlife, or lifting heavy things at the gym. I’m on the hunt for a fantastic postdoctoral position that will allow me to continue studying different communities of living things in other ecosystems, and that factors that affect how they’re put together, and I’m excited about the many opportunities out there!