I am deep in the Alaskan Arctic,  300 miles from the nearest road system, attempting to conduct the kind of science that usually requires a specialized laboratory. We rowed 30 miles of meandering flatwater today, bringing our total to 200 river miles in 12 days since we landed at a lonely gravel bar on the headwaters of Ambler River in Gates of the Arctic National Park.

Mosquitoes spangle the tent canopy arching over me. Backlit by summer solstice sun, the silhouettes of the insects make an inverted night sky of shifting constellations. The sun never sets on the banks of the Kobuk River this time of year. It hangs high above the horizon even now at 11 p.m., transforming my tent into a solar oven as I, ironically, work to uncover the secrets of a frog that can turn into ice.

… Read the rest of the article here.

Update (Nov. 2020): And, I’m especially thrilled that our piece will be the cover article for the journal, featuring a pair of breeding wood frogs from our population! My hands nearly froze trying to get this underwater shot, so I’m glad it was worth the effort!

Over the past 20+ years, our lab has been monitoring over 50 populations of wood frogs at Yale Myers Forest. Each year in early spring, we listen for the duck-like clucks of the male frogs which means that they have emerged from under the snow and moved into the breeding ponds. Shortly afterward, we head out into the freezing ponds to count the egg masses as a way to monitor population density over time.

In this study, we looked at how the oviposition date (the day on which frogs deposited eggs) has changed over time. As climates warm, we usually expect for the timing life-history events (like oviposition, emergence from hibernation, flowering time, etc.) called ‘phenology’ to advance in the year as winters get shorter. That’s just what most species do. And the trend of advancing phenology is strongest for amphibians.

Given that annual temperatures at our field site have increased by almost 0.6 C in the past two decades, we expected frogs to breed and lay eggs earlier. If our frogs were like other amphibians, we might expect oviposition to come around 6 days earlier.

Surprisingly, we found the opposite. Our frogs seem to be breeding 3 days LATER.

To figure out what might be going on with our frogs, we decided to look more closely at climate across the season, not just annual averages. It turns out that most of the increase in annual temperatures are felt later in the summer, but relatively less when frogs are breeding. Snowpack, on the other hand, is actually accumulating later and lasting longer. In the figure (Fig. 3 from the paper) below, you can see these trends. On the left are the comparisons between temperature, precipitation, and snowpack between 1980 and 2018. On the right, we plot only the difference in trends over time. At the top-right, we plot the oviposition dates to show how seasonal changes in climate line up with frog breeding.

We also looked at how the timing of oviposition correlated with climate across the season. We found that breeding occurs later when there is more snow at the beginning of the breeding window. Also colder temperatures just before breeding correlate with delayed oviposition (which makes sense if colder temps mean more snow and less melting).

So, we think that frogs may be kind of stuck. Persistent snowpack might be keeping them from breeding earlier. But at the same time, warmer summer temperatures might be drying up their ponds faster. If so, this could be a big problem for tadpoles that need to maximize their time for development. The figure below shows that frogs tend to breed earlier when winter and early spring air temperature are high. As we’d expect, more snowpack correlates with later breeding. High precipitation during the spring delays breeding (probably because it is falling as snow).

Twenty years is a long time to be collecting ecological data, but it is a pretty short window into the evolutionary history of wood frogs. And, we don’t know how long snow and temperatures may have been working against these frogs. So, as a final piece of our analysis, we used a machine learning technique called a random forest to predict oviposition dates backwards in time an additional 20 years. It doesn’t seem like much has changed over the past half-century or so. In one way, that could be good news in that at least things don’t seem to be getting any worse.

The big question is, how will frogs cope with these climate changes? If tadpoles are faced with an ever-shrinking window of time to develop into frogs, will they be able to keep up? Or, will they lose the race and end up as tadpole-shaped raisins in our ponds?

I won’t give away any spoilers, but I’m looking at our long-term larval datasets to ask that question next.

After sleeplessly struggling through my own quals, and afterwards reflecting on the process with friends, I’ve compiled my thoughts/suggestions/tips into this post for those staring down the barrel of their exams.

I’ll admit that I had never heard of qualifying exams until well into the first year of my PhD, and I had absolutely no idea what they entailed or how they transpired. I’m a first generation student, so maybe most folks are better familiarized with the concept. For those who are academically naïve like me, scroll to the end for an overview of the quals process.

Tips for quals:

Prep:

In my experience quals felt a lot like running a marathon through a Ninja Warrior gauntlet, while wearing a T-Rex costume and being chased by a flock of angry mallards.

In other words, you’ll have a lot on your plate. You won’t want to stop for day-to-day chores like paying bills and cooking dinner. Prior to your exams, I suggest trying to preemptively clear as much off your to-do list as possible so that you won’t be distracted nor will you compound your stress load.

For instance, you might pre-pay your bills, do a big grocery run to stock the kitchen with brainy-stimulating snacks, and even pre-prepare freezer-meals to last the duration of your exams. Set your email auto-responder to a plea-ful apology. If you are really savvy, you might even consider giving your partner a few extra backrubs or doing a couple extra chores for your labmates in an effort to bank some reciprocity points that you can cash in for favors during your exams.

Studying:

In some institutions, it is common for committees to give reading lists of critical papers prior to the exams. This isn’t common in my program, but nonetheless, there were about a hundred papers I knew that I would want to have at hand and a few hundred more that I wanted to be able to recall quickly.

You don’t want to be spending precious minutes of exam time searching through databases for the right paper. So, make sure that you have a good reference software onboard and consider blocking out a chunk of time each day leading up to your exam organizing key words and folders you expect to be relevant to your topic.

It is also a huge timesaver to have a reference software that integrates with your word processing application. When you are in the zone, there is nothing more frustrating than breaking the flow to stop and figure out your parenthetical citations. (I use Paperpile and strongly advocate for it).

Do some mental calisthenics to prep your expectations:

Great, now you’ve read and cataloged the relevant literature, banked some favors, and stocked your fridge—you are prepared for your exams! …right?! No matter how confident your feel about your exams, there is bound to be a point during your writing when you may come to one or more of the following realizations:

• There is a lot more literature on your topic than you thought
• You missed a whole boatload of important papers
• Your points are not original
• You know nothing
• Everyone else is smarter
• You will certainly fail your exams
• It might not be too late to go into law school
• Maybe being a barista for the rest of your life wouldn’t be so bad
• Perhaps it would be preferable to live in a cave in the woods forever
• Etc

I call this the “Dark Times”–when the gravity of your examination flattens any modicum of confidence and extinguishes all motivation but the desire to eat Nutella by the spoonful and rewatch the entire first season of the Office in bed.

I’m sure there are countless self-help blogs littered with suggestions for coping with stress, anxiety, and melancholy. But, for now, I share my preferred mind-hack that worked well for me during quals—a mind-hack that comes courtesy of the Stoic philosopher Seneca: “premeditation malorum” (The literal translation is “meditate on future evils.”) The idea is to think about all of the bad things that could happen and all poorer potential alternatives to your situation, thereby vaccinating yourself from the emotional distress if those bad scenarios come to fruition. For example, a few critical remarks from a committee member during orals might be emotionally difficult to take in, but if you’ve been imagining an even worse alternative wherein your exams ends with your committee hurling cabbage and screaming insults, a few critical remarks are no big deal in contrast.

Meditating on poorer alternatives puts things in perspective. After all, when you really think about it, the exam process is just sitting down to do nothing but think about one topic  for a few entirely undistracted weeks (presumably, since this is the topic you’ve chosen to dedicate your life to, this is probably a topic that you are really interested in). If you imagine that you could have spent those weeks endlessly swimming away from hungry sharks, or listening to Dave Mathews Band on repeat, or continuously flossing… the quals seems like down-right eudemonia in contrast.

Another mind-hack is to remind yourself of the purpose of qualifying exams—to push you into the shady corners of your own knowledge and the rarified boundaries of your field. If you start to feel like you don’t know anything, that’s a good sign that you are uncovering a gap in your own knowledge, a gap you can spend the next few years filling. Or, maybe you’ve discovered an unexplored horizon in the field that you can spend the next few years illuminating.

Try to keep in mind that the purpose of quals is to show you what you do not know. Quals are kind of the antidote to academic Dunning-Kruger effect.

It might also be helpful to remember that your committee would never have let you initiate the exam process if they did not expect you to succeed. If you were able to answer all of their questions with ease it would be less of an indication of your expertise than an indication that they failed to their design questions well enough

Plan a perspective parallax:

I hit two severe “Dark Times” during my written exams. In both cases, the thing that halted my unchecked plummet into existential duress were unplanned conversations with peers who had already gone through the exam process. It came as such a relief to hear that they had shared many of the same feelings during their exams. It was heartening to hear that they too discovered papers they missed, to hear that they questioned their entire graduate prospects, and to know that despite it all, they came through the process successfully. Sometime that simple perspective-check from an empathetic peer is a powerful tool to steer your thoughts away from the perigee of despair.

Celebrate:

After my exams, I went to the bar to celebrate. Over beers I had to confess that I kinda liked the process. Yes, it was stressful. Yes, I would not want to revisit the Dark Times. But, I am also incredibly grateful for the chance to spend four solid week thinking about these topics. I recon I learned as much in those weeks as I did in the previous three semesters. The task of explaining a topic to someone else is an entirely different ballgame from convincing yourself that you understand a topic, and doing so solidifies your understanding unequivocally.

At the end of the process, don’t forget to celebrate. More importantly, remember to celebrate your peers going through the same process. After all, we’re all inhabiting this Ivory Tower together, so let’s make it a party!

What are qualifying exams?

Qualifying exams (a.k.a. Quals, Preliminary Exams, Candidacy Exams, etc) act like a turnstile on the path toward one’s dissertation. The purpose of these exams is to demonstrate that you possess the requisite substrate of knowledge in your field. A passing mark on qualifying exams is an endorsement that you are ready and able to define a novel research topic and carry it through into a dissertation. With the exams successfully completed, a PhD student is said to advance to candidacy for a PhD degree, and becomes a PhD candidate.

The structure of the exams is different at every institution, but most seem to include written and oral components. Other than that, the form of exams seems to be widely diverse and variable even between programs in the same institution. So, rather than analyze all of the many exams structure, I’ll quickly explain how exams worked for my program at Yale School of Forestry and Environmental Studies (FES).

At FES, exams tend to center around a student’s prospectus, a document outlining a student’s research plan for their dissertation. For the first year or two of one’s PhD studies, the prospectus is a living document that helps in formulating research questions and outline a plan for answering them. Concurrently with crafting a prospected research plan, students are expected to begin putting together a committee. This is the committee that will preside over the qualifying exam and usually is also the group that will eventually assess the final dissertation. In my case, I have four committee members, all of whom are experts in various aspects of my proposed research.

At FES, the convention is to draft an extremely thorough and extensive prospectus with a full introduction, methods, analysis, and preliminary results sections, most of which will be imported into future publication and the dissertation. Over the months leading up to the exams, the prospectus is floated around to all of the committee both to refine it, but also to give the committee a sense of what the student might be missing.

I planned to take my exams at the end of my third semester (which was pushed back to the beginning of my fourth semester), which is a littler earlier than average for the program. Most students qualify in their fifth or sixth semester.

In FES, the exam is structured in two parts. First, the committee delivers 2-3 essay question that the student is allotted 2 weeks to return answers. After a brief break, the committee convenes to for the oral component. In the oral exam, the student gives a presentation of the prospectus and then the committee gets about 2 hours to ask questions about the prospectus and the student’s answers to the written component. Once the committee has sated their questions, they go into close-door deliberations, and within a 15-30 minutes wither accept, accept with reservations, or deny the student’s advancement candidacy.

The whole process is unequivocally nerve-wracking. After all, you just spent months developing a research plan, then invited a panel of the top experts in that field to grill you on your short-comings over the course of 3-4 weeks. Although it tends to reduce even the most confident PhD student into a sobbing, melancholic, mess of existential-crisis, I unrepentantly appreciated the opportunity and hopefully came out with some tips for other soon-to-be PhD candidates.