Hi Olivier,

your question is difficult to answer. On the one hand, not every insect species has been studied (or even described) yet and there are millions. On the other hand, demonstrating the absence of something seems unattainable. At best, we can say that we have made our best effort looking for it, but found nothing.

There are some insect species for which the absence of sex pheromones has bee believed during longtime (as for instance, some kissing-bugs), but they have been eventually found. Yet, sensory ecology may provide some insights about the relevance of chemical communication in a given insect species. if for instance acoustic, vibratory or visual communication is particularly developed, maybe that pheromones play a more limited role than, for instance in moths. The same if the characteristics of the environment makes it difficult. This does not exclude, however, the possibility that pheromones would be involved in close orientation, mate recognition or other steps in sexual interactions.

Best regards,

Claudio

Hi Olivier,

your question is difficult to answer. On the one hand, not every insect species has been studied (or even described) yet and there are millions. On the other hand, demonstrating the absence of something seems unattainable. At best, we can say that we have made our best effort looking for it, but found nothing.

There are some insect species for which the absence of sex pheromones has bee believed during longtime (as for instance, some kissing-bugs), but they have been eventually found. Yet, sensory ecology may provide some insights about the relevance of chemical communication in a given insect species. if for instance acoustic, vibratory or visual communication is particularly developed, maybe that pheromones play a more limited role than, for instance in moths. The same if the characteristics of the environment makes it difficult. This does not exclude, however, the possibility that pheromones would be involved in close orientation, mate recognition or other steps in sexual interactions.

Best regards,

Claudio

Prof. Lazzari gave a very good answer to this question. I have a small remark on this topic. Despite a lot of effort in our lab. and others, there are still lacking the evidance of chemical communications in anyLiriomyza species, such as Liriomyza huidobresis. These insect pests belong to Diptera, Agromyzidae.

Strictly speaking, proof of absence is an unattainable task. Your question should be re-written in a way that you can experimentally test it.

Dear Olivier

Please, find here an interesting paper.

https://www.nature.com/articles/s41598-017-17327-9

yes, indeed, by "proof of absence" I meant in which lot of efforts have been done to attempt to found sexual pheromones but nothing has been found yet.

Thanks Olivier for clarifying your question. There are certainly examples of searches that requested long-time and even unsuccessful. What seems to me interesting, and may help to give a biological context to your question, is to what extent pheromones (volatiles or contact) are the most efficient (or adaptive) sexual communication system for a given species, taking into account its particular biology and habitat. In this sense, sensory ecology may provide some insights. In other words, your question can be turned the other way around and become “are pheromones indispensable for sexual communication in all insect species?” My guess would be probably not.

Good modification!

Male bedbugs jumping on any objects having the size of a potential sexual partner may be a proof of absence of sexual pheromones in these species. Nevertheless, the nymphs have developed specific anti-aphrodisiac pheromones and males specific behaviour (+ emission of the alarm pheromones) in order to avoid homosexual mating.