Fish as smart as chimps at choosing partner for tasks

Fish are as good as the humankind's closest relatives chimpanzees at choosing the best partner for a task, a new Cambridge study has found.
The research shows that coral trout can now join chimpanzees as the only non-human species that can choose the right situation and the right partner to get the best result when collaboratively working.
Coral trout are fast when chasing prey above the reefs of their habitat, but can't pursue their quarry if it buries itself into a hard-to-reach reef crevice.
When this happens, the trout will team up with a snake-like moray eel to flush out the fish in a remarkable piece of interspecies collaboration: either the eel takes the prey in the reef, or scares it back into the open so the trout can pounce.

Coral trout - along with close relative the roving coral grouper - will use gestures and signals to flag the location of prey to an eel, including head shakes and headstands that actually point the eel in the right direction.
Field observations also suggested that they have a startling ability to assess when a situation needs a collaborator and to pick the right partner in the vicinity to get the best hunting results.

Now, for the first time, researchers at the University of Cambridge have cross-examined the collaborative capacities of these trout with the highly-intelligent chimpanzee using comparably similar experiments.

They found that the fish perform as well - if not better - than humankind's closest evolutionary relative when it comes to successful collaboration.
The trout even match chimpanzees in the ability to learn at speed which possible collaborator is the best candidate for the job.
The researchers caught wild coral trout and recreated hunting scenarios in set-ups that mirrored their natural environment, with the aim of creating experiments analogous to those previously conducted using chimpanzees - known as the rope-pull experiments - except relevant to the trout's habitat.
The trout were presented with out-of-reach food in the form of prey secreted in a crevice, and the possibility of a collaborator that took the shape of a model moray eel as fashioned by the researchers.

When conditions required collaboration, the trout were at least as proficient as chimps at determining when they needed to recruit a collaborator, doing so in 83 per cent of cases.
The study was published in the journal Current Biology.