Slow Learners

Giant tortoises have "surprising cognitive powers": (H/T Tyler Cowen) [bold added]

Galapagos tortoises at Honolulu Zoo

Tamar Gutnick and Michael Kuba at the Hebrew University in Jerusalem, Israel, and Anton Weissenbacher at Schönbrunn Zoo in Vienna trained Galapagos tortoises (Chelonoides nigra) and Aldabra tortoises (Aldabrachelys gigantea) to bite a ball of a particular colour — blue, green or yellow.

When tested three months later, the tortoises recalled the task. The authors tested three of the tortoises again after nine years and found that all three responded to toys of the correct colour. The researchers also found that both species of tortoise could be conditioned with fewer training sessions if they were taught in groups than if learning occurred in isolation, hinting that tortoises learn from watching their peers.

There are other slow-moving creatures that display unusual mental attributes. Memories can be transferred from one snail to another. And researchers have shown that elephants don't forget.

A lack of physical quickness could be correlated with mental acuity. It sounds plausible--until science proves this wrong, that's my story and I'm sticking to it.