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Full-Text Articles in Life Sciences
Comprehension Of Role Reversal In Chimpanzees: Evidence Of Empathy?, Daniel J. Povinelli, Kurt E. Nelson, Sarah T. Boysen
Comprehension Of Role Reversal In Chimpanzees: Evidence Of Empathy?, Daniel J. Povinelli, Kurt E. Nelson, Sarah T. Boysen
Sentience Collection
Four chimpanzees, Pan troglodytes, were individually trained to cooperate with a human partner on a task that allowed both participants to obtain food rewards. In each chimpanzee-human dyad, one of the participants (the informant) could see which pair of food trays on a four-choice apparatus was baited, but had no means of obtaining it. The other participant (the operator) could pull one of four handles to bring a pair of the trays within reach of both participants, but could not see which choice was correct. Two of the chimpanzees were initially trained as informants and adopted spontaneous gestures to indicate …
Vocal Recognition In Mexican Free-Tailed Bats: Do Pups Recognize Mothers?, Jonathan Balcombe, Gary F. Mccracken
Vocal Recognition In Mexican Free-Tailed Bats: Do Pups Recognize Mothers?, Jonathan Balcombe, Gary F. Mccracken
Sentience Collection
Mother Mexican free-tailed bats, Tadarida brasiliensis mexicana, produce 'directive' calls while searching for pups inside cave maternity roosts. These calls consist of highly repetitive pulses of sound uttered in rapid sequence. Calls are sufficiently intense that they are perceptible above the substantial background noise within roosts at distances of at least 1m. Calls are stereotyped within individuals, and statistically discriminable between individuals. These characteristics are expected for vocalizations that function for mother-pup reunions, and are shared with directive calls described previously in other bats. Mother T. b. mexicana directive calls are statistically no less discriminable than are the isolation calls …