Science

New preprint: Don’t forget about your friends

Remember those friends you never saw anymore after they got hitched? Not in geese.

In our recently published preprint we show that barnacle geese keep hanging out with there favourite early-life social companions also after they pair up. Females show a break during the breeding season but display their social preferences again in the following winter. Males keep their prefered companions throughout the breeding and wintering season and these companionships were predicted by familiarity and genetic relatedness.

We also show that especially males were aggressive during the breeding season towards both males and females and this possibly hampered their female partners to hang out with their own ‘friends’ during breeding but not winter.

In summary, our study reveals the robustness of social bonds formed early in life, carrying over across pair formation, even after extended temporal disruptions. Our findings thus highlight how the early-life social environment can have life-long consequences on individuals’ social life, even in monogamous species.

Reference
RHJM Kurvers, L Prox, DR Farine, C Jongeling, L Snijders (2019)

 

Science

New publication: Repeatability of signalling traits in the avian dawn chorus

Our newest open access paper on repeatability of avian signalling (song)  traits just came online in the journal Frontiers in Zoology.

Repeatability, consistent individual differences, in signalling behaviour is interesting because it means that those receiving the signal (i.e. listening to the song) could reliably learn something about how the individual singer compares to other singers/competitors.

We repeatedly recorded the dawn song of great tit males throughout the breeding season and show that start time of dawn song and repertoire size are individually repeatable both before and during the egg-laying stage of the mate (when she is fertile). Surprisingly the time a male started singing appeared to be more repeatable (consistent) than repertoire size, despite that the start time was also influenced by variable overnight temperatures. Start time was also more repeatable before than during egg-laying and we suggest that this is related to the behaviour of the (assumingly) intended receivers of the song, the females.

For a subset of the singers, we also explored a potential link between the absolute song trait values, the repeatability of these values and personality. We did not find a link but follow-up studies with a larger sample size, and including additional song traits, will be needed to confirm the true absence of such a link.

Reference
Naguib M, Diehl J, van Oers K, Snijders L (2019). Repeatability of signalling traits in the avian dawn chorus. Frontiers in Zoology 16: 1-11.
https://doi.org/10.1186/s12983-019-0328-7 

Science

New publication: Supporting ape rights: a comment on the role of science

Autumn 2018, friend and colleague Edwin van Leeuwen asked me an intriguing question: if I was interested in co-authoring a comment on an essay about Nonhuman rights? This was a topic we had talked about before and I find very fascinating, timely and relevant. So of course I said yes.

screenshot

The central essay and our comment, together with other comments, are part of a special issue on the topic of Great Ape Personhood, published by the ASEBL Journal (Association for the Study of (Ethical Behavior)•(Evolutionary Biology) in Literature; St. Francis College, Brooklyn Heights, N.Y.).  As so nicely explained by the editors (Gregory Tague and Christine Webb) in the introduction of this special issue: with his essay, Professor Thompson tries to bridge the false divide between natural science and humanities. Working from the foundations of philosophy and legal theory [and subsequently discussing important focus points for future research], he tries to reach scientists and their thinking in the battle for great ape personhood.

“Thompson relies on Nonhuman Rights Project attorney Steven Wise, who calls on scientists to awaken the thinking of judges deciding the fate of great apes. Perhaps it’s an unfair analogy, but Thompson attempts to do with primatology what climatologists from several generations tried to do – demonstrate how science is part of and can dramatically affect public policy. Thompson shows how what is empirically rational in science is treated differently in the legal arena, and that difference poses a real problem in the question of granting personhood status and other rights to great apes.”

Several interesting comments were made on the essay, both from philosophers and scientists. Edwin and me commented i.a. by suggesting some alternative ways science could support the quest for Great Ape Rights.

This project was definitely out of my comfort zone. And I see that as a good thing. Thompson’s essay and also the philosophers’ brief, written in support by a group of  philosophers, have given me many new insights about the role of philosophy and science in society. How together, philosophy and science can have some very important things to say about the way we live in this world.

The complete issue can be found here.
And (only) the comment made by Edwin and me, here.

Reference
van Leeuwen E.J.C., Snijders L. (2019) A comment on Thompson “Supporting Ape Rights: Finding the Right Fit Between Science and the Law.” ASEBL Journal 14 (1), 46-48.

 

Science

New preprint: 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.

BioRxiv

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.

Lysanne_field
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.

Reference 
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.

 

Science

New publication: the guppy 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.

Reference
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.

 

Science

New preprint: 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: http://thebrainissocool.com/2017/12/19/peer-review-is-not-all-that-is-cracked-up-to-be/%5D. 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.

Guppies_BW_Snijders