The Controversy Over Callous Carboplatin-Procedures

Note that at this age, the first social bonds form among ravens, but these are still strongly affected by kin relations (Braun and Bugnyar, 2012; Loretto et al., 2012). Subjects and their partners remained the same throughout the experiment, and to avoid reciprocity never changed roles. However, each subject did serve as a partner for a different individual other than his or her own partner (for actual subject-partner dyads see Table ?Table11). Table 1 Name of subject and partner, sex and rank of subject, and the total number of transfers and subsequent exchanges by the partner (transfers/exchanges) in the 4 different conditions. Subjects (and their partners) were Carboplatin tested in two adjacent test compartments that were separated by wire mesh. Each bird was tested as subject 4 times in all 4 different conditions (test condition, social control condition, non-social control condition, and motivation control condition; Figure ?Figure1);1); i.e., 16 times in total. The order of conditions was semi-randomized such that each individual went through 4 subsequent runs of all four conditions, each run starting with a different condition. The subject and partner's position in a condition in either the right or left testing compartment was counterbalanced for each individual over the 4 repetitions. Neither subjects nor their partners were tested more than once per day. Figure 1 Schematic representation of the different conditions in which the birds were tested in experiment 1. (A) Test condition; (B) Non-Social Control condition; (C) Social Control condition; (D) Motivation Control condition. Test condition (Figure ?(Figure1A1A) At the start of the test condition, the subject received 10 tokens (which were casted into the test compartment by the experimenter). However, the subject did not have the opportunity to exchange the tokens with the experimenter, since the red table (where they were trained to exchange) was placed in front of the adjacent test compartment where the partner was present. If the subject transferred a token to its partner through the wire mesh, the partner could subsequently exchange the token with the experimenter. If this chain of events occurred, only the (exchanging) partner would be rewarded with a piece (1/8th) of a dog biscuit (frolic?) and verbal praise. Consequently, the transfer of a token from the subject to the partner was considered a ��prosocial�� act. Non-social control condition (Figure ?(Figure1B1B) To test whether prosocial acts were not due to an attempt to bring the tokens as close to the red table as possible, we performed a non-social control condition. This condition was similar to the test condition, however, without a partner present in the adjacent cage.