Data from: Orangutans (Pongo pygmaeus) recognize their own past actions

The ability to recognize oneself in a mirror is known as self-recognition,
whereas delayed self-recognition is the ability to recognize the
relationship between current self and past actions. While 3-year-old human
children have self-recognition without the ability for delayed
self-recognition, 4-year-old human children demonstrate the capability for
both. Chimpanzees, the most closely related species to humans, have
displayed the ability for delayed self-recognition. However, little is
known about whether this ability is shared amongst all hominid species. In
this study, we examined whether orangutans, the most distantly related
species to humans within the hominid group, could recognize their own past
actions using the preferential-looking paradigm. Our results demonstrated
that orangutans were able to discriminate between a delayed video of
themselves presented after a 2-second delay, and a recorded video of the
day prior. This suggests that orangutans have the ability to relate their
own past actions to current actions, although we found no evidence of
self-directed behavior. We believe these findings will contribute to our
growing understanding of hominid self-recognition.