More guppies on the preprint server

After my good experience with the first preprint publication, I recently uploaded my second preprint on the BioRxiv server. I am really excited to share these cool new findings, especially since this study almost did not happen.


Fieldwork is always full of surprises, including flash floods (2018) and cars being stolen (2016). The year of this study (2017), we got stuck on Curacao because our airline was grounded (due to airplane safety concerns, we found out later). Curacao is a great island to spend some time, but it just lacked our favourite little fish: guppies. Luckily, we were able to get new flights and make it to Trinidad a couple of days later.

I love working with guppies, because they allow us to answer some very interesting questions about social living. Guppies live in rainforest streams and in the dry season they often end up in separate pools. These little fish thus naturally experience a variety of physical environments (pools) and social environments (the other fish in the pool). We take advantage of this natural system by trans-locating individual fish to different pools with different social compositions. Most animals would try to go back to their original environment, but for guppies experiencing new physical and social surroundings is just part of their ecology. That we can experimentally control their (social) environment is important, because it allows us to go beyond correlation and ask questions about causality, e.g. how does social composition influence individual foraging success?

To answer this question, we introduced individually marked wild guppies in single sex (male or female) or 50:50 sex compositions, to different pools and studied individuals’ social behavior and their ability to locate novel (experimentally introduced) food patches.

Me, being fascinated by guppies

Male guppies found fewer novel food patches in the absence of female guppies, while female patch discovery did not differ between single-sex or mixed compositions. We argue that these results were driven by sex-dependent mechanisms of social association: males reduced sociality when females were absent, while less social individuals found fewer patches. Females were, however, similarly social with or without males. Finally, males, but not females, preferred to join females over males at food patches.

Our study’s take-home message: for a more thorough understanding of social evolution, it is important to consider how individual (e.g. sex) and (sub)population-level traits (e.g. sex composition) interact in shaping the adaptive value of social living in the wild.

Maybe also: don’t fly with Insel Air.

Snijders L, Kurvers R.H.J.M, Krause S., Tump A.N., Ramnarine I.W., Krause J. (2018) Females facilitate male patch discovery in a wild fish population. BioRxiv.


Conservation, Science

New publication: Systematic reviews and maps as tools for applying behavioral ecology to management and policy

Yeah! Our recent open access paper on systematic maps and reviews in behavioural ecology is now available in, how appropriate, Behavioral Ecology. It is the first concrete output of a group of behavioral ecologists, passionate to effectively contribute to wildlife conservation. This is just the beginning! Many thanks to Oded Berger-Tal, Alison Greggor and Dan Blumstein for bringing us all together.


Summary of the paper:

Although examples of successful applications of behavioral ecology research to policy and management exist, knowledge generated from such research is in many cases under-utilized by managers and policy makers. On their own, empirical studies and traditional reviews do not offer the robust syntheses that managers and policy makers require to make evidence-based decisions and evidence-informed policy.

Similar to the evidence-based revolution in medicine, the application of formal systematic review processes has the potential to invigorate the field of behavioral ecology and accelerate the uptake of behavioral evidence in policy and management. Systematic reviews differ from traditional reviews and meta-analyses in that their methods are peer reviewed and prepublished for maximum transparency, the evidence base is widened to cover work published outside of academic journals, and review findings are formally communicated with stakeholders. This approach can be valuable even when the systematic literature search fails to yield sufficient evidence for a full review or meta-analysis; preparing systematic maps of the existing evidence can highlight deficiencies in the evidence base, thereby directing future research efforts.

To standardize the use of systematic evidence syntheses in the field of environmental science, the Collaboration for Environmental Evidence (CEE) created a workflow process to certify the comprehensiveness and repeatability of systematic reviews and maps, and to maximize their objectivity. We argue that the application of CEE guidelines to reviews of applied behavioral interventions will make robust behavioral evidence easily accessible to managers and policy makers to support their decision-making, as well as improve the quality of basic research in behavioral ecology.

Key words: applied animal behavior, conservation behavior, evidence-based management, literature review, meta-analysis, policy impact, systematic maps.

Link to the paper

O Berger-Tal, AL Greggor, B Macura, CA Adams, A Blumenthal, A Bouskila, U Candolin, C Doran, E Fernandez-Juricic, KM Gotanda, C Price, B Putman, M Segoli, L Snijders, BBM Wong, DT Blumstein. (2018) Systematic reviews and maps as tools for applying behavioral ecology to management and policy.” Behavioral Ecology.


New guppy publication: the background stories

I am very proud to share my latest publication in Nature Ecology Evolution (NEE). It is the first paper from my ‘guppy’ postdoc at the Leibniz-IGB. It is also the first time (I think) that a manuscript of mine got accepted by the first journal I sent it to, which is also nice for a change :-). Guppies were also the topic of my final year’s highschool science project o, which makes this publication extra special for me. Fish are amazing creatures and I am happy I get to share their stories.

Next to our scientific article, I wrote two background stories:

Social individuals find more food – IGB-website
Guppy_colour_SnijdersHow do you find food when the food is never exactly present at the same place or time? Wild guppies living in the rainforest of Trinidad are faced with this vital question every day. Looking at guppies, it turns out that there are a few keys to finding unpredictable food: being social and surrounding yourself with females. Read more

Being consistent in a dynamic environment: a guppy story – NEE-website
Sometimes things happen that can give you a whole new appreciation of the study system you are working with. For me this thing happened this year. Read more

If you are more of a visual person, I also made a little Youtube video.

The research article can be viewed for free, but please contact me, for example via ResearchGate, if you would like to have the PDF.

Snijders L, Kurvers RHJM, Krause S, Ramnarine IW, Krause J (2018). Individual- and population-level drivers of consistent foraging success across environments. Nature Ecology and Evolution.



Guppies on a preprint server

This week I submitted a manuscript to a preprint server for the first time. This is a bit scary because a preprint is not peer-reviewed and so is missing a ‘security check’, something that always makes me feel a bit more at ease when communicating my results [but see: However, I think preprint servers are a great idea, because you don’t have to wait for months before you can finally share your results and show people what you are working on. More importantly, preprint servers provide a way, for those interested, to read your findings without having to pass a pay-wall. A version of your study will thus always stay open-access. So, I put my fears (somewhat) aside and decided to submit my recent manuscript to BioRxiv, before submitting it to a scientific journal.

In the manuscript, we describe a field experiment with wild guppies in Trinidad by which we studied foraging success in the wild. We tested if foraging success in the wild differs consistently between individuals and if these differences can be explained by individual traits such as sex and social type, but also by population traits such as sex-ratio. I think the results are very exciting and also somewhat unexpected. If you would like to find out more, then please read the preprint on BioRxiv.







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