Nothing too interesting... just common sense. One of the Customer Service representatives did say that birds have the intelligence of 3 year-olds, and the moods of 2 year-olds, and can pick up on negative and positive energy/attitude. Whether or not that's proved scientific, I think actually all pets are similar to the negative/positive attitudes. If they sense something wrong with their owners (the atmosphere of the home), they feel the stress themselves.
And of course, this was totally OFF-TOPIC... but that was what made the orientation a bit more interesting...