Montpellier Ecology and Evolution Seminars (SEEM). Seminar by Dr. Joël Meunier (Institut de Recherche sur la Biologie de l’Insecte (IRBI), Université de Tours / CNRS, France) on “Do micro-organisms influence the social evolution of their hosts? Lessons from the European earwig”.
Supported by the Labex CeMEB: http://www.labex-cemeb.org/fr/recherche/seminaires-en-ecologie-et-evolution-de-montpellier-seem
Okay good morning everyone so we’re going to start welcome to the seminar so as usual we are on a webinar mode so people online uh do not hesitate to report any technical issue uh in the chat and please ask your question rather in the Q&A Tab and we will allow to you
To interact with the room uh during discussion session and with that thanks very much and for introducing to the speak hello good morning so I’m very happy to present you Joel so I know Joel since a long time and peral he was working on ants and um he has done his
PhD with Michelle chapuza in Loan in Switzerland and then he went to to Bal to work on aing so his new model since since then in 2012 uh and then after that he moved to get an Professor position uh in Germany uh and finally he arrived to get
A position at the sen in 2016 at the place where I was at the time at the IR which is the Institute Research Institute working only on biology of insect and uh unfortunately I I left in 2016 17 to be here at the se but that’s why I invite Joel because
First of all in fact he he come from so he’s doing a cycle thank you Joel thanks a lot andv thanks a lot for the invitation so as you said actually I was born in Monier so I know the city quite well and but I have to say the
Last time I came on the campus was maybe 20 years ago and I have to say it didn’t change that much in terms of building so I somehow recognize the place anyway um so I’m very happy to be here to uh be able to um give you an overview of the
Of one one line of research we are doing in my group or we have been doing over the last maybe 10 years which is about social evolution in insect and how microorganisms could be linked to this social evolution in these kind of organisms and um so social life is clearly bous
Phenomenon in nature you can find almost all animal taxa from vertebrates to arrod which includes of course insects but you can also have it in araks and many other invertebr species and one thing however is that even if it’s present everywhere it’s not the only way
Of life so you have you still have quite a lot of species that are soliter so major question is basically why we do have species that Liv in groups and others that remain soliter or the other way around and um this is parly of a problem because uh when you live in a
Group in general you have a high risk of pathogens and this is basically uh due to three main factors the first one is that as the covid-19 teached us uh basically there is a high risk when you live in a group to transmit the pathogens to other group members or to
Receive the pathogens from other group members the second main issue is that in general when you live in a group in nature um you have um a relatively High genetic relatedness between group members that mean that if there is a genetic um somehow a genetic weakness the this weakness would be shared among
All group members and the same kind of pathogens can come and kill all group members or affect all group members at the same time the third problem is that when you live in a group in general you also have a high Nest Fidelity and you can build a nest or modify the
Environment to improve the development of your Offspring but the same condition May improve the development of microorgan organisms in the environment so basically if we focus on the three main issues we should not have group living in nature nevertheless we do have group living in nature and so one of the major
Question is basically how group living did manage to evolve despite this inherently high risk of pathogens in the environment and well the answer to this question is based on again two pillars the first one is uh relying on the individual immunity so the immunity that everyone has which is also called the
Personal immunity and which typically involves um physiological immunity like basical the immune system and behavioral immunity where you going to avoid to go to infected places for example but when you live in a group you also have access to a second layer of defense and the second layer is called the social
Immunity which is basically when group members can help you to improve your defense against the pathogens and this concept of social immunity has been developed let’s say 15 years ago and mostly in new social insects where I don’t know okay um where um the the the different forms of social
Immunity have been described so you have Al groming where one individual will groom another individual to remove external pathogens you have in some termites for example you have alarm behaviors where some animals going to shake the body when there is a risk of pathogen infection you have the use of
Um natural components uh with kind of self-medication uh with the use of resin in some ant species where they bring back the resin into the colony and this resin has some antimicrobial property that going to protect group members from the inside and you have sanitary and hygienic behaviors where basically the
Animals going to remove cpses or uh or infected animals from the rest of the colony so as I said all these examples have been mostly described in new social species so that at some point it was trusted that um social immunity is something that is very specific to you
Social species and that is something that has secondarily evolved because the animals did not have uh well had to live in groups they didn’t have the possibility to live by themselves and to escape from this R but the problem is that um well the question remained the
Pen at some point because nobody really investigated the presence of social immunity in non new social insect and so an alternative hypothesis would have been that social immunity is actually the driver of social of sociality by itself because it allows solitary animals to get access to an additional
Layer of defense against the pathogens so is it something that is specific to your social ises or is it something that comes with the evolution of group living per se and as I said the main issue is that when you think about social Evolution you have a long transition between
Solitary and usocial species and you have a lots of different stages and different forms of social life and to date most of the knowledge about social immunity is focused on this new social system which is very untangled very derived and there is not so much information about whether it’s present
Or whether we do find some of these forms along the the the evolution of social life and there is one particular step that is very important to focused on which is um at the very beginning of the transition between solitary and group living which is about species that
Are gregarious so that live in groups and they do have a family life where you have parental care so these two things are the first steps in the evolution of social life and what is also important is to focus on species where these two steps are facultative so that mean that
Any time in their life cycle they have the possibility to live by themselves or to live in a group and there we can test whether they have benefits of living in a group to have access to social immunity and this is basically what I um have ined investigated over the last 10
Years mostly focusing on these species which is the European earwig for fular Oria um that you probably know here um this is a female this is a male you can recognize the sex based on the shape of the forceps so the female have straight forceps and the males have cured forceps
At least we’ve learned something today and um what is interesting in these species is that they do have a social life first there is forms of social interaction in term of matal egg care so the female start to lay eggs at the beginning of winter and then all of
Winter for about two month she will stop feeding stop doing anything else than providing care to the eggs and these forms of matal care is obligatory if you remove the mother the eggs going to die after um egg production after egg care then the eggs will hatch and the female
Will remain with The Offspring for about two weeks and during this period She will provide lots of care she will provide them these foods but these forms of family life is facultative so if you remove the mother The Offspring are able to forage for themselves and basically can survive very well without
Mother and then you have the adult stage where they do form groups they are highly gregarious you can have groups of up to three or 400 animals and um this is basically the rest of the life cycle is about this group living but here again this group living is facultative
So they can basically live by themselves so here we have species where we do have family life the gregarious form of life and all of them are facultative so every animal at any point in its life cycle has the possibility to leave by themsel or to join the
Group so um we did investigate whether um living in a group of having access to matal care indeed provide some benefits to The Offspring or to the animals in general and for example here so in principle this is a video it’s supposed to be moving but here uh you have a
Mother and here you have have the the eggs here and what we have found is that uh if we indeed cover the eggs with with the spores or fungus then the mother will increase her grooming activity and clearly remove the eggs the the spores from the eggs so basically for The
Offspring in terms of eggs there’s a clear benefits against pathogens of having a mother around then what we found also is that the way the female build the nest may also depend on the presence of pathogens and here you have two petri dishes uh where you have sand here you have the
Female with the eggs and here is the same the female is just smaller with the eggs as well and here you see the female dug into the scand and actually build quite sophisticated Nest where here if you manage to see it the female only Pro produced the eggs on on the ground so
She didn’t actually build anything and what we found out is that this is actually driven by the presence of pathogens in the environment which is not the case here so if there is a risk of pathogens infection for the eggs in the environment not on the eggs but just
In the environment then the mother will build is more likely to build a sophisticated nest and the last thing we have shown uh last example here is that so we have The Offspring here so this is again a petri dish you have The Offspring and what you see which is
Shown by the red arrows are actually their feces so they’re living on their feces and what we found out is that these feces have antimicrobal properties so that basic Bally the mother and The Offspring keep the feces into the nest lay the ground of the nest with their
Own feces to basically protect or prevent the growth of uh different types of microbes in the nest so they can sanitize the nest with their own pieces which is not something to do at home um but then the question we had is okay all this were shortterm benefits so
Clearly benefits of matal care in a very short period do mother can provide care or benefits against pathogen infection over the long term and so one thing we recently explored is whether this post osition care could actually allow the mother to transfer s some um immune factors to The Offspring for the future
Development and this is based on the recent development of knowledge about the acquired immunity invertebrates where it has been shown now there is quite a lot of papers that shows that if you infect or you immune challenge a female or even a male and then you wait
A bit then this animal will develop a kind of protection that can be specific or not specific to the to the pathogen that have been exposed before and there is a form of acquired immunity that has been shown and then there are other papers that show that this acquired
Immunity can be transferred to the Next Generation so if the female is primed with the pathogen before osition then she will transfer something into the eggs and when the eggs will hatch that will produce new adults that get the same protections so having a mother that is challenged before production actually
Is beneficial for the transmission of the of the of the protection to the to the desate the problem oh well this um is called the transgenerational imun priming and it has been explored in quite some invertebrate species so here we have a pyen that shows uh different
Uh groups of invertebrates when you see there are between squares that mean that the presence of transgenerational immune priming has been investigated here you have the number of species in each order where it has been investigated and when it’s gray it’s um the the proportion in
Species where it has been found so here well it has been investigated in one species which has tgip here in deep Tera it has been exp investigated in five species but only one had tgip just for you to know ear wigs are here these are the Mata and at that time
We had no knowledge about the tgip so the thing with tgip is that it’s very efficient it has been shown to be present in in many species but there is a major issue which is that it implies that there is not so much mismatch between the pathogens that the mother
Will encounter before of the position and the pathogen that The Offspring of the next generation will encounter when they become adults and well that might be the case but here our hypothesis uh was that maybe this mismatch could be somehow corrected by having parental
Care so if we if a mother or father that provides care to the apring or to the eggs is um contacting the pathogens while they provide care if they manage to transfer something then they will reduce the distance and the risk of mismatch between the two points the
Problem is that whether P care can mediate this transfer of immunity has actually never been investigated in vertebrates so uh but surprise surprise this is what we decided to investigate in ear wings and so the first step was to know whether we do have forms of f priming so first of
All we want to know whether actually there is something that could be transferred so our females that are primed better resistance against an infection later on so what we did is we had four treatments so females that were providing care so all these females were uh taken 47 days after um
After egg Lan so the eggs are out the female is taking care of the eggs and then we take the female and either we inject the female with a high level of dead bacteria so this is the bacteria we used so high concentration of dead bacteria which is a strong immune
Challenge a low concentration of the Dead bacteria which is a m immune challenge or we injected with PBS which is used as a control just for control for the effect of wanding and then we had a pure control where we did not do anything to the
Mother after that we wait seven days and then we injected all the females with a live bacteria concentration of bacteria with ld50 so which is supposed to kill of the females in about 21 days and then we checked whether the treatment had an effect on their
Resistance so this is what we have here on the bottom we have the days after injection so over 21 days and here the cumulative survival rate of the females between zero and one means all females are alive this is what we have for the control so the female that we did not
Manipulate at all and the good point is that we are about 50% of survival or death after 21 days which was supposed to be um our little concentration so that that’s that was great now what was more surprising is that um this is the survival of the female that were
Injected so Prime with a highest concentration of dead bacteria and what we see is that these females actually survive less well than the control females once they are injected with live bacteria so that mean that there is a kind of um cost of immune challenge so you first activate the immune challenge
With a high concentration of bacteria there is a cost of activating this immunity and then we when we inject a Le bacteria then the cost is already too high and then the female will die earlier this is what we have now what we have with the uh low concentration of
Of bacteria is basically no different with the control so it’s really linked to the the threshold that which we activates the immunity what was more surprising is the result we have with the PBS injection and with the PBS injection which is as I said a control
Just for the effect of wounding with the PBS injection we do have an immune enhancement so that mean if we have a female we inject them or we just want the female and seven weeks later we inject them with a live bacteria then this female Will Survive better than if
We didn’t do anything with a female before or if we injected the female with uh bacteria as well so um well the good point is that there’s something going on there’s a immune enhancement so when we do something to the female it affect whether the female is more or less
Likely to survive to the to an infection what was more surprising is that we had this effect with PBS and not with dead bacteria and so so this phas some questions the first one is what kind of of immunity or immune response is triggered by the PBS is it a sustained
Immunity so that mean we harm the female she activates her immune system which is very stay high for seven days and then when we inject the female with the living bacteria then it will be already activated and so it will be very efficient or is it a recalled immune
Response so it’s activated with the with the wanding and then it decreases and then it’s reactivated and more efficient patient once we have the the pathogen the live pathogens the second big question is about the fact that this is about with PBS so it’s not a specific immune challenge it’s a non-specific
Immune Challenge and what is a bit surprising is that it’s somehow suggest that this uh non or that the specific immune challenge nfy the effect of the wanding because in these two scenario we also have PVS so it’s bacteria plus PVS so having the bacteria nfy these
Benefits and this is a kind of question and the largest question is that again it’s a PBS so if it’s wanding it’s very non-specific it is very frequent at least in insect and so it rais questions about the evolution of such a system because we could expect that almost all
Animals at some point will be wed and so how this could be maintained over time and over generation and well these are just all non anwered question nevertheless we had a form of not immune priming but at least immune enhancement with the PBS and so the next question
Was to know whether the female can actually transfer this immune enhancement to the Next Generation via matal care to do to test this we had exactly the same setup except that this time after we uh expose the female to the different uh treatments we let the eggs develop which takes about uh two
Month and then we have new adults then in these adults we checked many life history traits so for example the clutch failure here how many eggs managed to hatch um the developmental time of The Offspring The N weight the survival rate of the of the adults Etc none of this
Trait was associated with the treatment great so that mean then we can test really what we want so we have the adults and about one month after they became adults we did inject them with a lethal concentration of the pathogens and then checked whether the treatment
Of of the mother while she was Pro providing care actually increase or decrease their survival and what we found is more or less the same pattern here we have no difference between the control the the and the The Offspring from mother that were injected with dead bacteria but again from mothers that um
Were injected with PBS actually had a higher survival rate so that’s great because it shows that there is um this immune enhancement can be transferred to the Next Generation and that shows for the first time that it can occur via matal care after AOS so this is a process that can
Really help um The Offspring once the eggs have been hatched whether this is egg care whether this is nymph care or both is something that we are now investigating because well in our first experiment we the mother had access to the two types of care what is interesting here is that it shed
Light on the new benefits of care for The Offspring and this is kind of important because actually over the last decades we accumulated the number of of data that shows that in earwigs having a mother is not necess very good in different conditions actually the The Offspring survive less well if the
Mother is around or if there is bad conditions the mother is actually decreasing the uh the care than increasing it so here maybe we have something that may explain that at least in part why the juveniles have some benefits in remaining with a family and with a mother living and adopting the solitary
Life the last question is of course what is transmitted we have the PBS is doing something but what the mother does transmit to the next generation is it about antimicrobal peptides emoy or other molecules or cellular uh promoter of immunity this is also something we don’t
Know so this up to now I’ve only talked about U pathogens but microorganism as you all know is not only about pathogens it’s also about some beneficial microbes and symbion and there is um among them of course there is a big uh Rush uh on the the gut microbiota so this community
Of microbes that live in the gut of their host and now we know that they are able to affect lots of life history trait in their host there could be immunity physiology reproduction Behavior many many many different traits and um uh recently it has been suggested
That there is a link between this gut microbiota and social Evolution as well so the classical theory of social Evolution are keing selection re procity multi-level selection all of them are focused on the benefits of group living for a single individual so how they did get direct or indirect benefits of
Interacting with other group members or being in a group the thing is this novel hypothesis is actually very independent of this one and suggest that group May evolve due to gut microbal manipulation and this is because um first we have an accumulation of data now that shows that
The with the gut brain axis that basically all the microbes we have in the gut are able to manipulate um the host so are able to modify many many different things in the brain of the host and the behavior and all these parts there are also some data that
Shows that uh particularly in the context of parasitism that some microorganism are able to manipulate the behavior of the host in a way that improve their own Fitness and not the fitness of the host and here you have for example this classical example of fungi manipulation in ants so if you put
The two things together it might um make sense to think that the gut microbes might manipulate the uh the social life of their host to make them more social and by doing this increasing their own transmission to new host in this way that would mean that social Evolution or
The evolution of group living could emerge independent of the benefits of group living for the host itself but only for the benefits of the gut microbes that is present in in the host well this is a very um tricky scenario it has been investigated a bit
In in the last few years in different insects Co croches Locust termite hes and hands where basically what the research did is to uh provide them with antibiotics or to form selection lines with axenic lines so lines without gut microbi up and see whether um the the alteration of the gut microbiota induced
A reduction in the expression of social behaviors and it did wasn’t found for example in cootes and Locust is that the animals that get antibi biotic as garious or attract less specifics they may be more aggressive they have social interaction and social networks that becom completely crazy or less efficient
And uh they may also increase aggressiveness in different context the thing is that all of this shows that gut microbiota alterations makes social individuals less social it does not answer the opposite question whether which is whether gut micobiota make solitary or poorly social animals more social which is the hypothesis I was
Interested so surprise surprise again we tested this with ear another picture just to show you that they do have wings because nobody knows that um and why we use ear wigs and particular adult earwigs because they do form group as I said earlier up to 100 individuals and they were some reports
In the literature that says that some animals are more gregarious than others so we had a hint about the presence of natural variation whether animals are solitary or not and uh we know that in these aggregations they do Express a lot of behaviors that could allow the
Transfer of gut microbes from one house to another which is mouse to Mouse contact aling alag ET so what we uh decided to do is to uh process in three steps the first one we wanted to quantify this natural variation in aggregation level just to make sure that indeed we have some
Animals that are more social than others the Second Step then would be to try to see whether we have a link between um this natural level of sociality and the composition of the gut microbiota and the third step was to know whether we could manipulate this gut microbiota to make individuals more
Social so for the first step we uh went to the field we collected uh more than 1,000 females then we bring them back in the lab and we set put them up in in a setup like this where we have cameras and all animals are in arenas which look like
This and in these Arenas we had four cells in one cell we have a test female that was free to move all along the three cells and on the top cell there were three stimuli females that were actually connected to this cell with a kind of tunnel that allows antenal
Contact and visual cues but uh these animals were too large to go through this and this one to go through that so we we set up all these groups of female in this kind of um of setup and then we uh take a picture every hour for 72 uh
Hours so three days and then we checked on these pictures whether the female the test females were was here or not and basically from this we extracted an agregation scores from 0 to 72 72 means the female was always near specifics uh every for the three days for every hour
And zero means she was never so she was either here or here so this is what we have here um this aggregation scores from 0 to 72 and here the number of females in each of these scores and this is the result so as you see well there are some
Variations uh these variations are non-normal and non-uniform distribution here is expect from a random distribution and here is another expectation from a random distribution so something is going on but uh the main question was still to know okay we have a scores but does it make sense so what
We did is we extracted the score per day and we checked whether what we recorded on the first day was correlated with what we observed in the second day and the third day and Etc so we try to see whether there is some consistencies in the in the scores we uh recorded and
Lucky us this is exactly what we had so even if there’s lots of points everywhere if you look at here we have we do have correlations between the aggregation scores from one day to another whatever the day is and here you do have the sampling weeks because this
Is this was a setup that allowed us to uh film 66 females per week so we had to repeat it for five weeks to reach a large enough number of reputes so here what we have is uh we just confirm what was U reported in the literature that
Indeed we do have some natural variation in whether females are more or less social so then what we did is we tried to see whether um they do have a different microbiota so we from this this U distribution we extracted we selected the most gregarious female and the least gregarious female we um
Dissected them extracted that guts and using a bioinformatic pipelines we actually ended up with um microb taxa that were present in the gut so we use sequences and this is what we have so here we have the the all the females with the low aggregation scores so the
Le least garious females and here you have um well the distribution of the the gut microbiota so each color is a different microbial family and well you see that blue and different colors so the main question was what do we have with the most garious females do they have something that is completely
Different or is it complet completely the same well second option unfortunately it’s not very obvious there is not something that is uh clearly obvious about the fact that most on the least garious females have different microbot and it’s not only a matter of observation so if we go into
The calculation of the different indices of of that well it confirms the first impression that clearly there is no possibility for us to disant whether a female is highly garus or or poar on the gut microb Community but the question was not only about the community it was maybe about the
Presence of certain microbes that could make them more or less social so then we checked at the sequences and and uh if we use a sequence we do indeed find a total of of pen sequences that should be able to discriminate between the two categories so we’re very happy but the
Problem is that that was about the sequences now if we check at the individual level so the host level here you have the different sequences that were supposed to be discriminant and here you have the 20 females with the low aggregation 20 female with a high aggregation and here you have the number
Of female that carry this quences and as you see this is not very convincing so basically there is no U no sequences that are only carried by 20 females in one category and not the other so in term of sequence that just mean that in the entire pool a few females
Contributed a lot in the number of sequences that well basically covered the entire pool but it was not very convincing at the host level so well um we did not manage to really shed light on the link between that but nevertheless we wanted to see whether we could manipulate it because
Here sies were based on the bacteria and maybe in the gut microbiota there is other parameters other components that could influence anything so what we did is we tried to manipulate this gut microbiota so here again we selected females from that were poorly gregarious or highly gregarious
And uh we dissected them we extracted them guts and we give that guts to feed to females that were poorly garious this is a species that is highly highly cannibalistic so it’s very easy you extract the guts you give it to a female and she will eat it
Immediately and so we have poorly uh gregarious females that were fed with gut from poorly gregarious females and poorly gregarious females that were fed with guts from highly gregarious females so our expectation here well so we give them uh feed and then we measure the aggregation scores of the change in
Aggregation scores between the two processes here there were our predictions so um this is the change in aggregation score zero meaning there is no difference before and after positive values mean that they become more gregarious and negative values that they became less gregarious that were our predictions and this is what we
Found well nothing so basically uh here what we show is that the the the origin of the gut transplant actually do not modify whether a female will become more or less garious it seems to be completely independent what was more surprising is that if you look at the
Two scenarios uh well the gut transplanted females all of them became more gregarious which doesn’t make sense at least according to our hypothesis and so this is a this is a kind of a big question and for that we have different interpretation the first one is there is temporal variation aggregation scores so
The life cycle of the earwigs is that at the beginning of of of Summer the new adults and new females are highly gregarious and at the end of the year they become more and more solitary because then they will have to produce their own eggs and they become solitary
To lay the eggs and so maybe here what we have is we have something like a transition seasonal transition in whether or not there are garas which is completely independent to the manipulation we have done the other risk question is about the impact of the social environment on the agre
Aggregation scores because we always tested them with the same cons specifics and maybe this the the level of aggregation is driven by the cons specifics and not by the host itself so no effect or no link between gut microbiota and aggregation in ults um we also investigated U earlier about
Care EG care and and and nymph care so for this time we providing them with antibiotics the females for their entire life cycle and we measure the effect on uh the expression of a care and surprise surprise there was also no effect so we did the antibiotics did change the
Community of microbes in the gut of the of the females but this do not translate did not translate into a change in the behavior so overall well this shows that we clearly have no support for this very nice hypothesis uh at least with the earwigs and and the point is that if you
Really think deeply about these new hypothesis it’s not completely surprising to not find any evidence because actually the gut microbiota is um within the gut microbiota there is a fierce competition between members to actually um uh develop into the host and so if one microbes develop the manipulative strategies then it will pay
A cost uh for developing and evolving these strategies and the other will benefit from it and they will basically be out competed by all the others so there are some varable arguments that are uh in my opinion very convincing that shows that actually this kind of manipulation is very unlikely to to
Evolve and occur in nature um nevertheless it does with still have two questions the first one is whether uh actually the gut microbes of the host by itself is not very important for social Evolution but maybe the gut microbes of C specific is important it is known that
The gut microbes would influence the chemical composition of of other insect and this chemical composition of chemical signatures is kind of important to drive social interaction so maybe there is still a role for get microbes in in Social Evolution but not the way we thought about
It and the last point is about the general importance of gut microbiota in earwigs per se um because U basically what we showed earlier is that with the antim microbotics there is no effect on the on care but there is also no effect on any other life history trait we have
Measured in the Pena so now we are currently trying to develop axenic lines of the species to see what whether indeed we can do it and then to try to identify which component could be important for the life cycle and with this I will finish I
Would like to thank uh all the funders that gave me money to test non-significant stuff uh all the members of my group and in particular Mari Charlotte shut who is uh the pooc who is currently working on the good microbal stuff and she needs lots of resilience
Uh and also manuso who was at that time a master student who uh did the first experiment I presented earlier and of course I would like to thank you all for your attention thank you is there any question in the room yeah hi thanks for the talk it was
Really nice did you check if because microbiota is efficient for against parasites so will it be like uh or like easy to check if you parti partied some earwigs and they will like transfer microbiota or like increase their micro micro microbiota to fight parasitism yeah that’s a that’s a very good point
But actually never tested it that’s that’s one of the plans so I have a PhD students who is currently starting who just started a few weeks ago and who is actually uh focusing on this kind of questions so one thing we plan to do is to um to actually manipulate the gut
Microbiota one way or another and then to see and test whether there is an effect on the immune system by itself so does it activat or not the immune system and then to try to identify if it does which part of the gut microbiota could be involved in this things or not so
That this this link is something we we plan to do in the future but not for now okay now we have a question online by Tom nor hello thank you for your talk um I was wondering whether you looked at uh other things and bacteria in the gut I’m
Thinking in particular to microsporia actually in my lab we did some experiments on artmia and we we we found that those micros Pia did influence their aggregation level so that’s really something is directly relevant to to the question you were asking perhaps you you know the paper it’s I can give you the
Reference I gave the reference in the the comments uh excellent points no we didn’t check for that and I didn’t know the paper so I will read it helpful I send you I would send it to you thank you was a question I was uh wondering if you had in your uh for
Aggregation uh did you have a real controls without air wigs in the end and what was the distribution because the distribution you have looks very much like autocorrelation else I I agree there are some I mean this experiment took a lot of time and once we finished it we realized we could
Have done and that’s clearly one thing we should have done um um the other to to go deeper another issue here is that we don’t really know how it does change over time so what for for practical reasons we we we tested um the aggregation with for example a group of
Three females on one set and then we took the same test females several weeks later or several months later and then we test the aggregation scores with all the females and we did in some time with we did find correlation and sometime it was not correlated at all and again we
Don’t know whether it’s a seasonal issue or whether it’s only driven by the group of of attractant females and this is something we plan to do this year well next year uh to see whether actually we use the same kind of attractant whether they we always have the same level of
Aggregation so whether basically the level of aggregation is driven by the host itself or by the the specifics them or whether it’s completely random or at least driven by something else the def agree I mean this random distribution would have been a good control for that what was our
Question um like you say that the earwigs parental care is non obligatory is it’s experimental also on on the on SE in the field that’s a great question the problem with earwigs is that we we don’t know much about its biology in particular in the field because they are
Nocturnal and which makes it quite difficult to observe in a natural condition what we know is that uh in the field we do see clutches without Parents Without a mother so we know that in nature it’s possible for The Offspring to survive without or to be without
Mother for a long time and to survive without a mother what is sure is that most of our knowledge is based on laboratory raring and this is something that this is Major limitation here because of course we have standard conditions and F conditions and in such condition there are many species where
Family life becomes factive as well so I agree this is this is a very good Point hello I’ve I’ve known you for even longer um um slides where I wasn’t really paying attention what point of of the microbiome so you removed what they had and put something in or you added no again so what we did is we simply added
It so I mean the point is that the fact that we do not have a strong correlation between the aggregation sces the way we measured it and G microb somehow was a dead end for this experiment but nevertheless we wanted to go further and and just
We we tried so we just gave them additional gut microbiota so that mean that indeed maybe the manipulation didn’t work at all um which is likely according to the to the results so this is this was just a first step just to see whether as matter of luck or once it
Could work without in a very rough way and it’s not the case so of course it raises lots of questions and now a question online by Alis Manel hello Jo thank you so much for your talk it was super interesting um there is some publication in Oni bees
And bumblebees showing that you know like individuals like the new pup exposed to the feces of K specific um acquires the microbiota and it’s a necessary condition for them to then survive better to the exposure of a protozoa like a pathogens so do you think um in in your species it could be
Like saliva of the mother for example giving some microbios trrain uh to the pep and uh this way like this microbial exposure from the mother could explain the immune pattern later in life yeah well that thanks for the question that’s um that’s uh that’s clearly an hypothesis we’re working on
At the moment so we have now we’re analyzing the data so from marish charlot so the poog she did an experiment where we first follow um the evolution of the gut microbiota throughout development so through the different molds from the eggs to the adults and see whether the mold by
Itself basically Purge the microbiota or not and the result is that it does not and also we tested the the role of maternal presence of the gut microbiota so whether um first installi that remains with a mother they do have a different microbiote they have a mother
Or not and then whether this is also the case two months later whether they had mother or not during the development and we do do find some difference so the mother do transfer something that is present in the G microbot of The Offspring what they do transfer and how
They do transfer is basically the next question for now we are just describing the the the the the phenotype let’s say so yeah but that’s that might be very possible okay cool thank you I have a because at Z as you know there is some termite colonies I’ve heard about
That you try to give some guts of termite to your foru what for H because the microbiota must be very different and to see if there is an action of um well the earwigs they are um omnivorous and they’re also highly predate Predators so they do eat other
Insect all the time so basically the kind of manipulation with did is something that they do in nature with many other insects whether they do it does change their behavior or not I mean no we never actually tested it but that’s yeah that might be possible I
Mean the there is no reason that would be very surprising that just by eating another species that would completely change such a major life histor trait of them but if if yeah why not that’s something that could be test I mean indeed there’s plenty of earwigs that we
Want to get rid of so I can do I can do that who a question thank you very much