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bioRxiv · 10.1101/2021.10.27.465717

First evidence towards chemical self-recognition in a gecko

Szabo, B.·Ringler, E.
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Abstract

Self-recognition is the ability to recognise stimuli originating from oneself. Humans and most great apes show evidence of true self-recognition in the mirror test. They use their reflection to remove a mark that is only visible in the mirror. Not all animals, however, rely primarily on vision. In lizards, chemical cues are important in social interactions. A number of lizard species show chemical self-recognition but it has never been investigated in a gecko species. Here, we test the tokay gecko (Gekko gecko) a territorial species with parental care on their ability to discriminate their own skin and faecal chemicals from those of same-sex, unfamiliar conspecifics. Geckos show a higher response rate towards chemicals from unfamiliar individuals compared to self-produced chemicals and a water control. Lizards showed self-directed behaviour, responded stronger to skin chemicals and females responded more than males. Our study provides first evidence towards self-recognition and for a social function of chemical present on faeces in tokay geckos but further tests are needed to confirm true self-recognition. Tokay geckos are an excellent model species to investigate individual recognition to demonstrate more sophisticated social cognitive abilities than have previously been attributed to reptiles.

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Szabo, B., Ringler, E.. 2021-10-29. First evidence towards chemical self-recognition in a gecko. https://doi.org/10.1101/2021.10.27.465717

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