Interview de Ornela De Gasperin

Mis à jour 15-Avr-2021  

My background
I am a Mexican biologist. I grew up in one of the most diverse areas of Mexico and used to spend my holidays in the jungle. I was fascinated by animals that lived in societies and therefore decided to study biology. During my bachelor’s studies, I read about the genetic determination of the bees’ waggle dances and decided to do research to better understand how animals communicate. During my BSc’s I investigated how and why can signals convey honest information (using lizards as a study system), and how genetic and environmental factors co-determine the development of signals throughout the lifetime of an organism (using fish as a study system). From my PhD onwards I focused my research on understanding the causes and consequences of different family structures, primarily on why parents vary in how much care they provide to their young, and on how and why do evolutionary conflicts of interests arise between family members.

How did my interest in ants begin?
During my bachelor’s studies I learnt that some ants farm their own food (!), that they can take other ants as slaves (!!), that ant queens can live up to 30 years (!!!) and that their largest colonies can have 5 times the size of the biggest human city (!!!!).
I was dazzled by this diversity, but it wasn’t until I finished my PhD that I began to work with ants.

What was my PhD thesis about?
During my PhD I tried to understand why some parents abandon their offspring to their fate, whereas others die trying to protect them. And why sometimes two parents are needed to raise offspring, and other times only a father or a mother suffices. I worked with a beetle (Nicrophorus vespilloides) that has facultative biparental care. This beetle carries phoretic mites (meaning they use the beetles to disperse), and despite the mite’s ubiquitous presence throughout the beetle’s life cycle, its effect on the beetle family had been overlooked. I showed that the presence of the mite in a reproductive event reduces the number of offspring produced by the beetles. Fathers protect their offspring by abandoning them earlier, taking mites away with them and thus saving food resources for their young. The extent of care that parents provide to their young therefore depends on interactions with other species. And sometimes abandoning one’s young is the best way of protecting them. More broadly, the mite determined where did the outcome of an interaction between members of the beetle family fall within the conflict-cooperation continuum. And from the mite’s perspective, its interaction with the beetle similarly fell on a continuum from parasitism to mutualism depending on the ecological context and on the interacting individuals. My research therefore showed that labelling a species as ‘parasitic’ or ‘mutualistic’ may be misleading (and that reality is much more interesting!), as species can have different fitness effects on males and on females, and on younger or older individuals.

My current situation
I am a postdoctoral researcher studying the most complex animal families: ant colonies. I work with the Alpine silver ant, Formica selysi, a fascinating system that has discrete variation in family structure within populations (and that lives in beautiful places in the Alps). Colonies host either a single or many queens, and queen number is determined by a ~30-million-year-old chromosome (analogous to our X/Y sex-determining chromosome). Some of the research lines that I am following are these: i) what forces maintain this genetic polymorphism (i.e. why hasn’t one of the two chromosomes gone to fixation); ii) how do individuals carrying alternative chromosomes behave, including how do young queens disperse and start a new colony, how they vary in morphology, and how their morphologies correlate with their lifespan and success at colony founding; and iii) how do different family structures affect the survival of individuals living in them under different ecological conditions.

3 ants (or other animals?): the most beautiful, the most interesting and the most bizarre
More than species, I have always been fascinated by life history strategies. I describe three that surprised me and drove me into research (even if I have not worked on these questions directly):
Migration, specifically in Monarch butterflies. As a child, I visited the Monarch butterfly sanctuary in Michoacán, Mexico. I was stunned by the idea that a butterfly migrates ~7,800 km, from the Rocky Mountains to Michoacán. How do they “know” where they are and where have to go to, and when? How can such a complex behaviour evolve?
Sex determination. Why can individuals of some species change their sex throughout their lifespan, whereas others, like us, have chromosomic/genetic sex determination? Why is sex sometimes determined by the environment and other times by genes? For those that do change their sex throughout their lifespan, why do individuals of some species change from male to female, and individuals of other species from female into male?
Slave making ants. Some ant species carry out raids during which they attack other colonies, kill adults, and steal the brood. The brood will grow in their captor’s colony, they will work throughout their lives to help their master’s colony grow, develop, and eventually capture more slaves. How does such a life history strategy evolve? What defences have slaves evolved to fight back? Are slave makers more successful when they specialise in slaving a single species or multiple species?

3 publications, including the one you consider the best and the one that required the most work, and the one that caused you the most problems.
De Gasperin O., Blacher, P. B., Grasso, G. & M. Chapuisat. 2020. Winter is coming: harsh environments limit independent reproduction of cooperative-breeding queens in a socially polymorphic ant. Biology letters, 16, 20190730. https://doi/10.1098/rsbl.2019.0730
I consider this to be one of the best publications I have, and the one that required the most work. It is an experimental proof of an implicit assumption that lacked testing for decades. It required rigorous thinking to spot gaps of knowledge in theory, and creativity to link analogous life history strategies between vertebrate and invertebrate species. It’s also the one that required the most work, as I had to combine laboratory and field work within a day for several weeks, thus working from 7am until after midnight or later every day, including driving 3hrs a day to collect ants in the Alps.

De Gasperin O., Duarte, A., Troscianko J. & R.M. Kilner. 2016. Fitness costs associated with building and maintaining the burying beetle’s carrion nest. Scientific Reports, 6, 35293
This is my favourite publication from my PhD research, as it was the first independent idea that I had. During my PhD I worked with a burying beetle that prepares an edible nest for their young using a small vertebrate carcass. They rip off any feathers or fur and roll the carcass into a rounded ball of flesh. When I started working with these beetles, I was shocked by how spheric the nests were. I remembered that a perfect sphere is the shape that maximises the volume:surface area ratio, and I thought that the sphericity of the carcass-nest could be under selection. Specifically, because burying beetles add antimicrobial substances to the surface of the nest (which are very expensive to produce), a more spheric nest could provide more food (i.e. volume), while reducing the surface area that parents need to maintain. I teamed up with a colleague who wrote a script to measure the level of sphericity of the carcasses, and we found that only larger beetles were able to construct rounder carcass nests. We also found that rounder carcass nests were associated with lower maintenance costs, as I had predicted. More generally, this experiment showed that construction and maintenance costs are key to understanding animal architecture, a widespread assumption that lacked empirical evidence.

De Gasperin O., Blacher, P.B. & M. Chapuisat. 2021. Social insect colonies are more likely to accept unrelated queens when they come with workers. Behavioral Ecology, in press. Published in BioRxiv doi:
I really like this publication, because it assessed another implicit assumption that lacked testing. Ant workers living in colonies with related queens sometimes accept unrelated ones. This seems like a paradox, as workers do not gain indirect fitness through the reproduction of alien queens. It had been assumed that this is an incidental phenomenon resulting from a failure of workers at recognizing alien queens. And that workers living in colonies with multiple queens become worse at recognizing alien ones, as having many matrilines in a colony can increase the diversity of recognition cues within the nest. But we showed that workers living in colonies with multiple queens are as good at recognizing alien queens as workers living in colonies with a single queen, and that workers flexibly adjust their acceptance of alien queens according to the situation, and only accept them when the ecological benefits of doing so outweigh the costs of rejecting them.

Finally, some advice to give to a young person who starts.
1) Do not compare your progress to anybody else’s
Research varies. Some experiments fail, some work smoothly. Some experiments are fast, some are slow. Different lines of research are not comparable with one another. And a higher publication record does not reflect a better scientist!
2) Keep hobbies that make you happy in parallel with research
Scientific research can be challenging. Experiments can fail, papers can get rejected many times prior to publication. Keep at least one hobby that make you happy and that allows you to forget about research. During my PhD I discovered squash, and no matter how bad a day in the laboratory was, or how many times a paper got rejected, I always forgot about it and felt happy when I was playing squash.
3) Never stop reading about topics that are not about your own research line
Scientific research requires to read a lot of specialized literature, and to work on small details. Although this is an important aspect of scientific research, one can forget about the big picture when working on the details of a system. And little by little, you may forget why you started doing research to begin with. Reading about other lines of research, even if not about science, allows you to step back from the details of your own research and to keep track of bigger pictures. And inspiration for your own research can come from very unexpected places.
4) Celebrate the victories
Scientific research comes with rejections, failures in experiments, and fatigue. Take whatever little victory you have, and truly celebrate and enjoy it. Celebrate finishing an experiment even if later you find out that it failed, celebrate submitting a paper even if later it gets rejected. Take the all the spaces you can to celebrate and enjoy research.
5) “It helps to sometimes be a little deaf”
I read this advice from Ruth Bader Ginsburg, and it helped me to work effectively in science. Science brings together people from many different countries, with diverse personalities and with different working modes. And tight schedules and pressure puts people under a lot of stress when they are carrying out extensive work. Keeping a “deaf ear” will help you continue working effectively with your colleagues and bosses (but this does not mean that you shouldn’t stand up for yourself when needed!).
6) Draw your expected results prior to carrying out any research
Science has a replication crisis. Most results cannot be replicated. There are many causes for this phenomenon, and one of them is building post hoc hypotheses. And it is very easy to really believe that the hypothesis you are working with at the moment, after seeing some data, was the hypothesis that you had all along. Making drawings of what you expected to find, alongside with a few paragraphs of the background and hypothesis prior to carrying out an experiment can prevent you from strongly building/believing post hoc hypotheses.
7) Write every detail of your protocols immediately
Do not assume that you will remember details later on. Write all of them. Every. Single. Little. Detail. And with as much detailed description as you possible can, even if it seems absurd. Sometimes you use a dataset you collected years ago. You will need these protocols. I also find it useful to store data as photos (i.e. I always take photos of field and laboratory notes, so I never lose them).

Photos :

- Burying beetle :

- Formica selysi de Santiago Herce Castañón :

Ornella sur le terrain :