Page 215 - Emotions through the eyes of our closest living relatives- Exploring attentional and behavioral mechanisms

As such, we confirm that orangutans yawn contagiously in response to “real” orangutan stimuli, regardless of whether they are familiar or not. Furthermore, we cannot draw any conclusions on the rate of yawning. Importantly, self-scratching does not have a significant impact on the occurrence of the aforementioned results.
Appendices
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