Lead pollution, even at very low levels, affects bee learning

© Coline Monchanin

For the past 30 years, agrochemicals have been identified as important causes of pollinator decline. However, the impacts of other equally widespread pollutants, such as heavy metals, have received much less attention. These metal compounds occur naturally in the environment, but their use in industry, agriculture, and domestic applications has significantly elevated their concentrations in soil, water, air, and plants. Lead is of particular concern on a global scale and raises many public health issues related to lead poisoning and certain cancers. Despite the ubiquity of heavy metals in the environment, little or nothing is known about their effects on pollinating insects.

To test these potential effects, the researchers fed hives of honeybees nectar containing lead at low concentrations (below the European regulatory thresholds for the environment) for 10 weeks.

Read more on the INSB website

 

Reference :

Chronic exposure to trace lead impairs honey bee learning.

Monchanin C, Blanc-Brude A, Drujont E, Negahi MM, Pasquaretta C, Silvestre J, Baqué D, Elger A, Barron AB, Devaud JM, Lihoreau M.

Ecotoxicol Environ Saf. 2021 Apr 1;212:112008. doi: 10.1016/j.ecoenv.2021.112008. 

Contacts :

Coline MONCHANIN

Mathieu LIHOREAU

The drosophila is able to learn that A+B is not equal to AB

The fly is subject to a problem where two odors, A and B, are sequentially associated with electric shocks, after which these same odors are represented together (AB) without electric shock. When the fly is confronted once with this task, it tends to represent AB as the sum of two previously punished odors. On the other hand, when confronted several times with this task, the fly tends to represent AB as different from A and B alone. © CRCA

For the first time, Matthias Durrieu, Antoine Wystrach, Patrick Arrufat, Martin Giurfa and Guillaume Isabel from the CRCA have just experimentally showed that fruit flies can solve a more complex learning task.

This study was recently published in the scientific journal Proceedings of the Royal Society B.

 

Reference

Matthias Durrieu, Antoine Wystrach, Patrick Arrufat, Martin Giurfa and Guillaume Isabel

Fruit flies can learn non-elemental olfactory discriminations

Proc. R. Soc. B 287: 20201234.

 

Contacts

Matthias Durrieu & Guillaume Isabel

 

 

Studying animal movements with networks

What happens in an animal’s head when it moves? How does it look for food, sexual partners or a migration site? Does it plan its route or does it move randomly? Ethologists from the Centre de Recherche sur la Cognition Animale de Toulouse (CRCA-CBI / CNRS / Université Toulouse III Paul Sabatier) have joined forces with ecologists from the Laboratoire Évolution et Diversité Biologique de Toulouse (EDB – CNRS / Université Toulouse III Paul Sabatier / IRD), Researchers from the École Nationale Vétérinaire de Toulouse (ENVT), together with a company specialising in radio-tracking tools (Xerius), have developed a new methodology within everyone’s reach, based on network analysis, in order to simplify and characterise animal movements in space and time. This new study was published in the journal Methods in Ecology and Evolution.

The multiplication of automated tracking tools now makes it possible to easily obtain high-resolution movement data for a large number of animal species. At the most basic level, it is possible to visualize the sequence of animal positions by joining them by a line, i.e. plotting the animal’s trajectory. Speed, the distance travelled between two successive positions, the time spent in a specific position and changes in direction are some of the main parameters that can be extracted from this trajectory. Variation in these parameters tends to be correlated with changes in an individual’s behaviour. However, until now, these variations have provided little information on the time dimension of trajectories.

Read more (in french)

Reference :

Analysis of temporal patterns in animal movement networks

Cristian Pasquaretta, Thibault Dubois, Tamara Gomez-Moracho, Virginie Perilhon Delepoulle, Guillaume Le Loc’h, Philipp Heeb & Mathieu Lihoreau

Methods in Ecology and Evolution, January 2020. DOI: 10.1111/2041-210X.13364

Contacts :

The blob is capable of perceiving the stress of its fellow creatures

© Audrey Dussutour

Today, researchers are showing that they are able to perceive the stress of their fellow human beings and use this social information to avoid potential dangers. These results are published in the journal Philosophical Transaction of the Royal Society B.

The blob is a single-celled organism without a nervous system that inhabits moist, dark undergrowth. Scientists have just demonstrated that the blob can detect the stress of its congeners. This discovery follows a previous study that showed that blobs are able to detect the presence of their congeners in the environment. Indeed, when they feed, blobs excrete chemicals that are attractive to nearby blobs and that underlie their aggregation.

Read more (in french)

Reference :

Stress signalling in acellular slime moulds and its detection by conspecifics.

Briard L, Gourjade C, Bousquet C,  Dussutour A.

Philosophical Transactions of the Royal Society B. 18 May 2020. doi.org/10.1098/rstb.2019.0470

Contacts :

Collective intelligence in the face of nutritional challenges in ants

An individual-based model demonstrates that these impressive feats of nutritional compensation emerge from simple individual decisions. These results show that, by adjusting their feeding behavior at the individual level, ants sustain homeostasis at the colony level.

In ants, food is brought back to the nest by only 10% of its members: the harvesters. The food is then regurgitated and shared among all the members of the colony. How do the harvesters deal with food imbalances in the colony?

Reference :

Ant foragers compensate for the nutritional deficiencies in the colony

Csata E, Gautrais J, Bach A, Blanchet J, Ferrante J, Fournier F, Lesvesque T, Simpson SJ & Dussutour A

Current Biology 12 décembre 2019  https://doi.org/10.1016/j.cub.2019.11.019

Researchers contacts :

 

 

 

 

 

 

Abeilles – Une histoire intime avec l’humanité

This collective book, written by researchers from the CNRS and INRA as well as academics, reveals the fascinating world of bees – what they have, what they are and what they do -, deciphers the links they have with nature and humanity, the dangers that threaten them and us, while addressing the scientific solutions to face them.

Une histoire intime avec l’humanité

Under the direction of Martine Regert with the participation of Martin Giurfa (CRCA-CBI).
Preface by Jean Claude Ameisen
160 pages – 24.90 €
Editor : Le cherche midi

 

 

Ants, champions of traffic without traffic jams

Whether on the holiday road or on daily journeys, traffic jams affect both cars and pedestrians. Laure-Anne Poissonnier and Audrey Dussutour, researchers at CRCA and their colleagues at the University of Arizona, demonstrate that ant societies are protected from these problems and circulate with ease even when traffic is extremely dense. This way, their food harvest never loses its effectiveness. This work is published in the journal eLife on 22 October 2019.

Read more : CNRS press release (in french)

Reference :

Still flowing: experimental investigation of ant traffic under crowded conditions

Laure-Anne Poissonnier, Sebastien Motsch, Jacques Gautrais, Jerome Buhl, Audrey Dussutour

eLife, 22 octobre 2019. https://doi.org/10.7554/eLife.48945

Researchers contacts :

Bees and absolute numbers

© Maria Bortot

Researchers from the CRCA-CBI Toulouse have just demonstrated that bees not only can discriminate quantities relatively (one presenting more or less elements than the other) but also with an absolute representation of numbers.

This work, published in Biology Letters, shows that honeybees are capable to identify numbers independently of any relative comparison (more/less). The bees' sense of number seems consequently to parallel the Human's one, suggesting widespread numerical competence in animals and independent emergence of the sense of number in different branches of species evolution.

Read more on CNRS website (in french)

Publication

Honeybees use absolute rather than relative numerosity in number discrimination

Bortot M, Agrillo C, Avarguès-Weber A, Bisazza A, Miletto Petrazzini ME, Giurfa M.

Biol Lett. 2019 Jun 28;15(6):20190138. doi: 10.1098/rsbl.2019.0138. Epub 2019 Jun 1

Contact

Martin Giurfa

Centre de recherches sur la cognition animale (CRCA)

Centre de Biologie Intégrative de Toulouse (CBI)

CNRS/Université Toulouse Paul Sabatier

+33 5 61 55 67 33

Metformin promotes anxiolytic and antidepressant-like responses in insulin-resistant mice by decreasing circulating branched-chain amino acids

Depression is a major public health concern and one of the priorities in the field of psychiatry, notably to develop therapeutic strategies with a better efficacy than currently available antidepressant drugs.

A recent study led by Bruno GUIARD, professor at the University of Toulouse III, Paul Sabatier (Research Center On Animal Cognition / Center of Integrative Biology), provides experimental evidence that metformin, an oral anti diabetic, produces anxiolytic and antidepressant-like effects in insulin-resistant mice. This finding is particularly interesting in light of the therapeutic limitations of antidepressant drugs and pave the way to the identification of new targets for the treatment of psychiatric disorders in relation with the peripheral metabolism.

This finding is particularly interesting in light of the therapeutic limitations of antidepressant drugs and pave the way to the identification of new targets for the treatment of psychiatric disorders in relation with the peripheral metabolism. This study has been published recently in Journal of Neuroscience (J Neurosci. 2019 Jun 3. pii: 2904-18. doi:10.1523/JNEUROSCI.2904-18.2019).

Read more:

Model underpinning the effects of metformin on depressive symptoms in mice fed a HFD. Credit: Zemdegs et al., JNeurosci (2019)

Publication

Metformin promotes anxiolytic and antidepressant-like responses in insulin-resistant mice by decreasing circulating branched-chain amino acids.

Zemdegs J, Martin H, Pintana H, Bullich S, Manta S, Marqués MA, Moro C, Layé S, Ducrocq F, Chattipakorn N, Chattipakorn SC, Rampon C, Pénicaud L, Fioramonti X, Guiard BP.

J Neurosci. 2019 Jun 3. pii: 2904-18. doi: 10.1523/JNEUROSCI.2904-18.2019.

Contact

Bruno Guiard

Enseignant-Chercheur à l'université Toulouse III - Paul Sabatier et au CRCA / CBI-Toulouse

+33 5 61 55 63 36

Photo de Bruno Guiard

Bruno Guiard

Slime mould absorbs substances to memorise them

Fusion of venous network of two blobs © David Villa/ CBI-Toulouse / CNRS Photothèque

Physarum polycephalum is a complex single-cell organism that has no nervous system. It can learn and transfer its knowledge to its fellow slime moulds via fusion. How it did so was a mystery. Researchers at the Centre de Recherches sur la Cognition Animale (CNRS/UT3 Paul Sabatier)1 have recently demonstrated that slime moulds learn to tolerate a substance by absorbing it.

This discovery stems from an observation: slime moulds only exchange information when their venous networks fuse. In that case, does knowledge circulate through these veins? Is it the substance that the slime mould gets used to that supports its memory?

Read more on CNRS website (in french)

Logo pdfDownload the CNRS press release (english version)

 

Reference

Memory inception and preservation in slime moulds : the quest for a common mechanism.

A. Broussard, J. Delescluse, A. Pérez-Escudero et A. Dussutour.

Philosophical Transactions of the Royal Society B le 22 avril 2019.

Contact

Audrey Dussutour

CNRS Researcher, CRCA / CBI-Toulouse

+33 5 61 55 64 41