| Title: | Faeces' odours attract gregarious locust hoppers |
| Author(s): | Vernier C; Barthes N; Chapuis MP; Foucaud J; Huguenin J; Lemenager N; Piou C; |
| Address: | "CIRAD, UMR CBGP, F-34398 Montpellier, France; CBGP, Universite de Montpellier, CIRAD, INRAE, Institut Agro, IRD, Montpellier, France. Electronic address: verniercamille@hotmail.fr. Centre d'Ecologie Fonctionnelle et Evolutive, UMR 5175, CNRS, Universite de Montpellier, Universite Paul Valery Montpellier, EPHE, IRD, F-34293 Montpellier, France. CIRAD, UMR CBGP, F-34398 Montpellier, France; CBGP, Universite de Montpellier, CIRAD, INRAE, Institut Agro, IRD, Montpellier, France. CBGP, Universite de Montpellier, CIRAD, INRAE, Institut Agro, IRD, Montpellier, France; INRAE, UMR CBGP, F-34398 Montpellier, France" |
| DOI: | 10.1016/j.jinsphys.2022.104454 |
| ISSN/ISBN: | 1879-1611 (Electronic) 0022-1910 (Linking) |
| Abstract: | "Collective motion is one of the most impressive common features of gregarious locusts: once formed, bands and swarms get moving for long distances. It was shown that visual perception of neighbours plays a key role in maintaining marching behaviour at a local scale. But at a larger scale, mechanisms underlying band cohesion are less understood. It was shown in several field studies that individuals separated from the band were able to get back to the group, even after being separated since a night. In this context, faeces' odours could be a possible indicator of the recent passage of a group. In this study, we tested if nymphs are attracted by faeces' odours and if this effect is modulated by the age of the faeces. To this end, we conducted individual olfactometric behavioural assays of 3(rd) instar hoppers of desert locust, Schistocerca gregaria, exposed to odours of 1 h-old and 24 h-old faeces. We also used Gas Chromatography-Mass Spectrometry (GC-MS) to identify odours' volatile organic compounds from faeces. The results of behavioural assays indicated a strong attractive effect of faeces, with no preference for one of the two faecal age classes. Nymphs spent significantly more time in the side of the olfactometer where the faeces' odours came from, and 72.7% of tested individuals chose this side first. We filtered and annotated 11 volatile organic compounds present in both fresh and old faeces in GC-MS analyses, including guaiacol and phenol, which are known to cause an aggregative effect on desert locusts. As the attractive effect lasted over 24 h, band's faeces could still have an attractive effect when individuals are separated from the band since one day. In this situation, latecomers individuals would be able to get back to the group by following the traces of their predecessors" |
| Keywords: | Animals *Grasshoppers *Volatile Organic Compounds Odorants Nymph Feces/chemistry Band movement Behavioral experiment Gas chromatography-mass spectrometry Guaiacol Olfactometry Schistocerca gregaria; |
| Notes: | "MedlineVernier, Camille Barthes, Nicolas Chapuis, Marie-Pierre Foucaud, Julien Huguenin, Joris Lemenager, Nicolas Piou, Cyril eng Research Support, Non-U.S. Gov't England 2022/11/08 J Insect Physiol. 2022 Nov-Dec; 143:104454. doi: 10.1016/j.jinsphys.2022.104454. Epub 2022 Nov 4" |
