Crab-eating macaque findings. One of the most well known examples of experiments on crab-eating macaques is the 1981 Silver Spring monkeys case. In 2014, 21,768 crab-eating macaques were imported in the United States to be used in experimentation. The crab-eating macaque has the third-largest range of any primate species, behind only humans and rhesus macaques. The IUCN Red List categorizes the species as Least Concern, and CITES lists them as Appendix II ("not necessarily threatened with extinction", in which trade must be controlled to avoid use incompatible with their survival). A recent review of their populations suggests a need for better monitoring
Vestigial response throwback to the pointed ears of many mammals and just one more vestigial trace of man's evolutionary history. The focus on this part of the human anatomy has finally been followed by a much later observation testifying to our evolutionary past. The subsequent observation concerns an automatic ear-perking response seen, for example, in dogs when startled by a sudden noise. This response, though faint, fleeting and hardly discernible in humans nonetheless clearly manifests itself. This phenomenon is an automatic-response mechanism that activates even before a human becomes consciously aware that a startling, unexpected or unknown sound has been "heard". That