Jumping spiders seem to recognise each other if they’ve met before

Jumping spiders seem to be able to tell each other apart, putting them among just a few other invertebrates that are thought to have this skill.

Recognising individuals within your species is important for social animals, such as primates, but just a handful of invertebrates have been observed to have this recognition, for example Northern paper wasps (Polistes fuscatus). This is thought to help with social cohesion within the insects’ colonies.

Now, Christoph Dahl at the University of Neuchatel in…