Some snakes appear to reply in a different way to their very own scent when it has been altered, which hints that they’ve some type of self-recognition.

A handful of animals, together with roosters, horses and cleaner fish, have proven indicators of self-awareness in what is called the mirror check. This entails placing paint on an space of their physique that they’ll’t see and not using a mirror, akin to their brow. If the animal touches the mark when wanting within the mirror, it means that they’re conscious that the reflection is of themselves, and never a picture of one other particular person.

“However snakes and most reptiles primarily work together with their world by scent,” says Noam Miller at Wilfrid Laurier College in Canada. So he and his colleagues challenged them to another, smell-based model of the mirror check.

The group members collected the scents of 36 japanese garter snakes (Thamnophis sirtalis sirtalis) and 18 ball pythons (Python regius) by wiping cotton pads alongside their pores and skin.

They then introduced every snake with 5 scents: their very own, their very own with a little bit of olive oil added, simply olive oil, one in all one other snake of the identical species and one in all one other snake with a little bit of olive oil.

The garter snakes carried out extra lengthy tongue flicks in response to their very own modified scent in contrast with the remainder of the scents.

“They solely do lengthy tongue flicks once they’re curious about or investigating one thing,” says Miller, which means that the garter snakes can recognise when one thing about themselves doesn’t odor fairly proper. “They might be pondering: ‘Oh, that is bizarre, I shouldn’t odor like this.’”

Ball pythons, however, responded in the identical method to all of the scents. Garter snakes are way more social than ball pythons, says Miller, so it might be that social species usually tend to have self-recognition.

The findings are the primary proof of potential self-recognition in snakes, says Miller. “There’s this assumption that snakes, and practically all reptiles, are these sluggish, instinctive, non-cognitive animals, and that’s positively not true.”

Nevertheless, Johannes Brandl on the College of Salzburg in Austria questions whether or not this ought to be interpreted as self-recognition. “This interpretation solely turns into believable if a correlation with social behaviour might be established,” he says. In any other case, it might be argued that some snake species are merely extra inclined to work together with the experiment.