Wednesday, August 23, 2017

I have the Imposter Syndrome.

At a recent meeting, I had a long discussion with a student about their struggles with the imposter syndrome - not just having it, but even admitting they had it. I was moved and inspired. I asked the student if they wanted to post their story on my blog, anonymously if they chose. So here it is. I hope you find it as helpful, honest, and - indeed - inspiring as I did. (Andrew).

A few months back I was chatting with a friend and collaborator about my post-doc plans and options. He kept throwing what I felt were outrageous suggestions at me, funding that I wasn’t competitive for at all. I brushed the suggestions off. I told him that I would look into it, but needed to think more realistically, that I wasn’t in that league. He cut me off and said, “you need to get over this imposter syndrome thing.” To which I laughed and responded, “imposter syndrome? I think I have anti-imposter syndrome.”

I know anti-imposter syndrome is not a thing. But I really did not identify with the way that I heard imposter syndrome described. I had heard young PhD students talk about it as though it was an inevitable consequence of their genius. It was almost like humble bragging – “Oh of course I have imposter syndrome, I’m at _______“ (insert ivy-league institution of your choice here). I’ve never heard someone from a lesser esteemed school make such a claim. No, we know we are the academic scraps, having been rejected from far better schools for various reasons. Or at least that’s the mindset many of us have. I felt like people routinely under-estimated me. I don’t have imposter syndrome, I told myself. Quite the opposite, I was trying really hard to be accepted into a world I had longed to be a part of for so long. I knew that I would prove myself worthy if given the chance. I had so much confidence in myself and my abilities. I had an “I’ll show you who I am” kind of attitude, and it worked for me.

Actually, it worked really well for me. Doors opened. Connections were made. Suddenly I was receiving awards and praise from some well-known people. People not only accepted me once they saw what I was capable of, but for the first time in my academic career, people had expectations of me! Overnight it went from “who are you” and “you’ll probably fail but go ahead and try” (yes that was actually said to me), to “you always give such great talks” and “I can’t wait to see the results from your next project.”

And with that my friend’s words came storming back into my mind. Maybe I did have this imposter thing after all? For so long I believed in myself when few others did. I had felt like I belonged somewhere that I wasn’t being accepted into. I felt a need to prove myself. And now that things were finally falling into place and I was accepted, I couldn’t shake the thought that “maybe they were right all along, I don’t belong here.” I felt myself spiraling into an anxiety induced despair as I stressed over not having published enough. This was fueled by comments from mentors like “you know your reputation exceeds your publication record” and “you have so many publications on this topic, oh wait, you only have 2?” And the chasm between my metrics of success and people’s opinion of me seemed to grow at an ever-quickening pace.

But I was still not willing to accept that I had imposter syndrome. Things came to a head over a 72 hour period at a recent conference. Expectations were high, reinforced by nearly every conversation I had. “Please expect less of me” I found myself timidly asking people. This was not me. I am not timid. My self-confidence was shattered and I couldn’t put my finger on why. I ignored it. I tried to psych myself up. But my usual mantra of “I’ll show them” was no longer valid. Instead I was grappling with an internal monologue along the lines of “I have to show them again. And again. And again. And if I don’t, they’ll know they were right before, that I don’t belong here.” I was one talk away from people realizing I was a one-trick pony, one conversation away from people losing their confidence in my abilities, one failure away from the confirmation of “you don’t actually belong here.” I felt like I was caught in a storm of expectation and praise that was wholly unwarranted and that I couldn’t possibly live up to.  I wasn’t worried that I wouldn’t give a good talk. I know I give good talks, it’s one of my strengths. But I was paralyzed with fear that silently people would be thinking “oh this is crappy science” and “her previous work was so much better, what’s this nonsense?”. And maybe this is where the root of my imposter syndrome comes from. I perform well, but that doesn’t mean my ideas are good – maybe people are just blinded by the well-thought out presentation and pretty slides and not impressed by the science itself.

The night before my talk I sent a couple of text messages to trusted friends admitting that my confidence was gone and that I was struggling with expectations. The next morning I woke up to a flurry of messages reassuring me. Before my talk I spoke with a friend about what I was feeling in person and she reassured me that she often felt that way too, and that I had no reason to doubt myself. My confidence temporarily bolstered, I stood up and delivered a great talk that was well received. And I realized then that I could never let myself get that worked up about expectations again. More importantly, I realized I needed to talk to people about this. And so, the rest of the conference I talked to some of my conference buddies about this “imposter” feeling I’d been having. I was shocked at how many people responded by telling me that they were dealing with it too. People who I admire, consider successful and confident, and who I wouldn’t have guessed experience this. Sharing our experiences was cathartic for me. 

I’m sharing this story because I’ve been told it’s a unique perspective on imposter syndrome. Maybe it is, maybe it isn’t. My story isn’t meant to teach you about imposter syndrome, or to describe what everyone feels. It’s my story, that is all. I agreed to post this because I didn’t think my experience fit with what I understood imposter syndrome to be. But when I was able to give a name to it and talk about it with others, then I could start moving past it. Who knows, maybe someone out there is reading this thinking “Hey, that’s my experience too!” And maybe this will help them begin to deal with it. I hope that someday I’ll move past this entirely, and that self-doubt will be fleeting and merely a check of my humility. Until then, I’ve found a few strategies that keep me grounded when I begin to doubt myself:

1.     I re-assess my self-worth. I now keep a list of the compliments I get and screenshots if they are in digital form. I look at them to remind myself that I do belong and that the people I trust believe in me.

2.     I remind myself that I’m on track and re-assess my metrics of success. When I stress about my pace of productivity, I look up the CV of a young career scientist. Nine times out of ten, I’m right on track when I look at the pace and number of publications. Keeping my expectations and comparisons realistic is important. I’m right where I should be at this career stage, and I’m on pace to be where I should be at the next. More importantly though, I remind myself that everyone progresses at a different pace and there is no universal standard of success.

3.     I reinforce my accomplishments. I made a list of all of my awards, grants, invited talks, etc. When I need a little extra boost I look at the list to remind myself that so many people couldn’t possibly be wrong about my potential and my abilities.

4.     I talk about it. Not to everyone, but I have talked about this with a few trusted people and have been surprised to learn that they had similar feelings. This issue is far more common than we think it is. It is comforting to know that people I look at as confident and successful are dealing with this too. I can’t help but think if people were more open about this topic, then maybe I would have talked it through with my mentors instead of having a near meltdown over it. 

One final note, I have chosen to post this anonymously for several reasons. Feeling like this is a mental health issue that I do not want to be associated with is not one of them. On the contrary, I will gladly talk / commiserate with you in person. However, I did not want to open myself to judgement, assumptions, or personal attacks from people I do not know. I also did not want to invite personal compliments – this was not a humble brag and I don’t want you to tell me I’m awesome because you think I need to hear it. Actually, I think that would be counterproductive. To my friends, you probably know I wrote this, so thanks for being awesome. To those who don’t know who wrote this, I’m probably your student, post-doc, colleague, collaborator, or conference buddy – think about that.

Wednesday, August 16, 2017

Evolution in a common landscape: a tale of two stickleback species

All species cope to some extent with environmental heterogeneity. How do they achieve this? Do they tolerate or avoid extreme conditions? Or do they adjust to local selective environments through adaptive evolution? Many studies in evolutionary ecology look into these questions one species at the time. Yet, species do not live in isolation, but are assembled in communities. We might thus ask if members of the same community respond to environmental conditions similarly or in species-specific ways. Answering this question is important for understanding the eco-evolutionary dynamics of communities. Since anthropogenic impact on natural systems may simultaneously put multiple species at risk, a multi-species approach is also relevant for conservation and natural resource management. In a new article in Nature Communications, we investigate to what extent two stickleback species, the threespine stickleback and its relative the ninespine stickleback, evolve “collectively” across contrasting environments. That is, a tale of two stickleback species in a common landscape.

Evolutionary biologists have accumulated ample evidence for contemporary evolution in natural populations. Meanwhile, the question of why populations do (or do not) evolve and whether they evolve in a predictable manner will still keep us busy for quite some time. There are many species and many environmental contexts in which species can evolve. For as much as we know, the way populations evolve is species- and context-dependent – and thus highly variable. This is reflected in meta-analyses such as in last month’s issue of the American Naturalist, where Krista, Gregor, Caroline and Andrew illustrated that even when we expect populations to evolve in a predictable direction (i.e., parallel evolution), the extent to which they actually do so is highly variable (Oke et al 2017). Across species and environmental contexts, populations thus show anything from “very” parallel to “not-so-parallel” evolution. Aspects of evolution are thus not very predictable.

Things become clearer when focusing on one species at the time. One of the species that has been strongly fueling the debate of the importance of parallel and non-parallel evolution is threespine stickleback. Indeed, of the 92 studies included in Krista-and-friends’ meta-analysis, 26 studies featured this very species. One of the most convincing, wide-spread and best understood cases of evolution in nature is the rapid parallel evolution of reduced body armour (e.g. from high to low numbers of lateral plates and from long to short spines) when marine threespine stickleback populations colonize freshwater. Importantly, these populations often evolve in a predictable manner, but we also have a fairly good understanding for why they sometimes don’t. Gene flow, for instance, which homogenizes the gene pool and therefore slows down or halts adaptive divergence, explains some of the limits on the evolution towards low-plated populations in freshwater (Raeymaekers et al 2014). In another threespine stickleback ecotype pair, the lake-stream system, variation in phenotypic and genomic parallelism could not only be explained by gene flow, but also by the magnitude of the difference between the lake and stream environment, which has an amplifying effect on adaptive divergence (Stuart et al 2017). Studies like this generate a better mechanistic understanding of evolution, because they show how strong selection on ecologically relevant traits and their underlying genes has to be to contribute to local adaptation, and how often there is a common genetic basis for such traits.

Threespine stickleback populations can evolve rapidly from completely plated (top) to low-plated (bottom), while homogenising gene flow can slow down this process, even when selection on plate number is evident from one generation to the next (Raeymaekers et al 2014). Photo credit: Anna Mazzarella.

Yet, single-species studies hold a major limitation for the study of contemporary evolution in nature: they do not provide insight in the generality of contemporary evolution. For instance, the evolutionary versatility of threespine stickleback may be exceptional, and thus levels of adaptation in this species may be not representative of the typical strength of adaptation in nature. And of course, species do not live in isolation but are assembled in communities. Members of the same community often face similar environmental gradients, but do not necessarily respond similarly to these gradients. From a community perspective, it is important to understand the variation in these responses, in particular because adaptation to local selective environments in one species may also influence adaptation in other species (e.g. through competition or dilution effects). So, in order to fully understand biodiversity patterns across ecologically diverse landscapes, we should consider multiple interacting species simultaneously, providing a more holistic view on the landscape processes shaping biodiversity. This also makes sense for conservation and natural resource management, since anthropogenic impact on natural systems may simultaneously put multiple species at risk.

In our new study, we performed a comparison between the threespine stickleback and its relative the ninespine stickleback (Raeymaekers et al 2017). We primarily wanted to find out to what extent both species differ in evolutionary potential to deal with challenges along the broad habitat gradient over which they coexist. In western Europe, both species co-occur frequently at the exact same spots, which includes both freshwater and brackish habitats. Yet, both species also have a wide-spread geographic distribution, are closely related (allowing us to compare homologous traits and genomic regions), show interesting differences in ecology, and are highly abundant, and thus represent an excellent pair of species for this type of study. We sampled both species at four freshwater sites and four brackish sites, and then compared them for various aspects of population divergence. We analysed 1) whether the two species show phenotypic and genomic signatures of adaptive divergence along environmental gradients, 2) to what extent both species show parallel patterns of population divergence, and 3) what are the most important spatial and environmental drivers of population divergence in each species.

“Von dem Stichling”. Description of threespine and ninespine stickleback in “Fischbuch: das ist ein kurtze, doch vollkommene Beschreybung aller Fischen so in dem Meer und süssen Wasseren…” by Gessner and Forer (Zürich, 1563).With two and six dorsal spines, the drawings of both species do not look very professional. Yet, even nowadays the number of spines is a source of confusion. Threespine stickleback sometimes have four spines, and in Dutch the ninespine stickleback is called “tiendoornige stekelbaars” – or "tenspine stickleback". Based on my own counts, this is a more appropriate name.

One or two species of stickleback? Each student has to pass the test.

Here are our most important findings and some reflections:

1) Phenotypic divergence was significant for 50 % of homologous traits in threespine stickleback vs only 7 % in ninespine stickleback, while the proportion of outlier loci (SNPs which are likely genomic targets of selection) was at least 2.5 times larger in threespine stickleback. This confirms a stronger tendency to adapt in threespine stickleback. Since this is the first time that both species have been compared in exactly the same environmental matrix, we now know the effect of species-level differences in evolutionary versatility on population divergence.
2) These results do not imply that ninespine stickleback cannot adapt, since populations might already be preadapted to the environmental gradients in the study area. However, we observed a numerical advantage of the threespine stickleback in freshwater. We proposed that this relative ecological success could possibly be attributed to their evolutionary versatility. Of course, two species only represents a very small community, but it shows the potential of merging landscape genomics with community ecology to understand whether or not species evolve “collectively” across landscapes.
3) We observed substantial phenotypic, but no genomic parallelism between both species. This result demonstrates that the evolution of similar phenotypes in the same selective environments might primarily involve different genes. Based on previous comparative genomic studies, this result is not unexpected, but it is exciting to observe this in exactly the same spatial matrix. 
4) Note that we wanted our study to allow for a “fair” comparison of evolutionary versatility between the two species. We therefore compared both species for homologous traits only. Indeed, even if one species would be extremely variable for a trait which is missing in the other species, it would be hard to decide which species is most versatile. Luckily, most measurable traits in both species are homologous anyway (lateral plates, first dorsal spine, pelvic spine, gill rakers, fins, …). Non-homologous traits include dorsal spine #4, #5, #6, … #10 (guess which stickleback species is lacking those spines).
5) A reference genome is often used to facilitate SNP-typing. Yet, at present a reference genome is available for threespine stickleback, but not for ninespine stickleback. While it is possible to use the threespine stickleback genome as a reference for ninespine stickleback, we didn’t do this since this would narrow down the comparison between the two species to homologous genomic regions. Homologous traits do not necessarily have the same genetic basis, and hence the entire genome should be considered to allow for a straightforward comparison of evolutionary versatility. In addition, homologous genomic regions may already have gone through a long history of selection - perhaps pre-dating the origin of both species, and hence may bias our analyses in unexpected ways. In this respect our choice for de novo SNP typing in ninespine stickleback seemed more "safe". It is waiting now for the assembly of the ninespine stickleback genome to look into homology effects in detail.

The results are further discussed with respect to how differences in genomic architecture, gene flow and life history may induce or reflect variability in evolutionary potential and ecological success among species sharing the same landscape. Read more here.


Cited literature

Oke KB, Rolshausen G, LeBlond C, Hendry AP. 2017. How parallel is parallel evolution? A comparative analysis in fishes. The American Naturalist 190:1-16.

Raeymaekers JAM, Chaturvedi A, Hablützel PI, Verdonck I, Hellemans B, Maes GE, De Meester L, Volckaert FAM. 2017. Adaptive and non-adaptive divergence in a common landscape. Nature Communications.

Raeymaekers JAM, Konijnendijk N, Larmuseau MHD, Hellemans B, De Meester L, Volckaert FAM. 2014. A gene with major phenotypic effects as a target for selection vs. homogenizing gene flow. Molecular Ecology 23:162-181.

Stuart YE, Veen T, Weber JN, Hanson D, Ravinet M, Lohman BK, Thompson CJ, Tasneem T, Doggett A, Izen R, et al. 2017. Contrasting effects of environment and genetics generate a continuum of parallel evolution. 1:0158.

Thursday, August 3, 2017

Journal Life List

Steve Heard just posted a blog on his journal life list – all of the journals in which he has published and how his papers are distributed across those journals. Kind of like a birder’s life list of species. Dividing the number of journals by the number of papers gives a very rough JOURNAL DIVERSITY INDEX (JDI**) for an author – Steve’s is 0.61, which he expects to be high. Although I hadn’t planned to write a blog on this topic, it reminded me that I am always excited when I expand my journal life list, favoring JDI increase. Yet at the same time, I tend to target particular journals that I think are in my core research area, favoring JDI decrease. So I quickly (on the train home) did an analysis similar to Steve’s, with some additions.

At first blush, it is clear that my JDI of 0.28 is way lower than Steve’s, presumably because I tend to target core journals: Evolution, The American Naturalist, and Journal of Evolutionary Biology. But then second blush made me realize that the above contrasting motivations (increase diversity vs. focus on core journals) is a function of the joint combination of submissions and acceptances given submissions. Hence, I next did the same analysis but based not on where papers were published but on where I first submitted them.

The general trend, and indeed the JDI (0.23), are similar – suggesting that I really do focus on core journals over journal diversity. But this number is probably biased by a single journal – Nature – to which I have often submitted first but in which I have only rarely published.* Deleting Nature gives a JDF of 0.26, so I still tend to favor core journals over diversity. In fact, it is interesting that my JDF for submissions is lower than that for publications, suggesting that my rejection rate at the core journals is slightly higher than at other journals. I therefore next compared numbers of submissions to journals with numbers of publications in journals.

The two are highly correlated, as one would expect, with my core journals (apart from Am Nat) seeming to have roughly similar or higher than expected acceptance rates. Of course, the difference between these numbers are not strictly acceptance rates because I sometimes publish in journals, including my core journals, papers that I previously submitted elsewhere. At the extreme, I have published in 11 journals to which I never done a first submission of a paper. At the other extreme, I have submitted first to 4 journals in which I have never published a paper.

So, what to make of this beyond my apparent emphasis on core journals. Perhaps it is that journals should give out frequent publisher miles that might, for example, lead to waived publication fees. For instance, I have published 19 papers in Evolution, 17 papers in Journal of Evolutionary Biology, and 11 papers in Molecular Ecology. However, I don’t think I have really had to pay publication fees for most of those. Maybe better would be discounted attendance at annual meetings – yeah, I like that.


* I have included (for ease of generating this quickly), all publications in a journal even if they are introductions or notes or comments or news pieces. For example, my publications in Nature are News & Views and the like. 
** This is just a quick and simple metric - see Steve's blog for more comments on it.
*** Perhaps my favorite bird cartoon is below - simply a gratuitous plug for

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