&gt; these creatures who have displayed startling emotional depth (Koko and her pet cat, anyone?)<p>I&#x27;m not convinced that Koko is much more than a long-term, well-publicized Clever Hans. Can you explain what emotional depth you think is evidenced in this case? If possible, please do so without relying on the interpretation of Koko&#x27;s main caregiver, who does not seem to abide by scientific principles.