http://lljcwddkoyjq3xxtchl7a4i3ig6wqrg7nfxuzbzj4k4tbnb6pnzq7kid.onion/index.php?title=Animal_cognition&oldid=771
For example, several studies have shown that performance is better on, for example, a color discrimination (e.g. blue vs green) after the animal has learned another color discrimination (e.g. red vs orange) than it is after training on a different dimension such as an X shape versus and O shape.