Additional file 7: Table S2. of Vocal exchanges during pair formation and maintenance in the zebra finch (Taeniopygia guttata)

Response strength for each pair each day each combination. Within a time window of interest of 4 s before and 4 s after call onset for our cross-correlation histograms we counted the number of calls. We divided the time window with a binwidth of 50 ms (i.e. 160 bins in total). The number of calls in the bins in the first 0.5-s (Nbase, i.e. the calls between 4 and 3.5 seconds before the focal calls) was used as baseline and those in the 0.5-s bins after call onset (Nresponse) as the response. We calculated the response strength index for each call combination for each pair for each day as follows: Rresponse = (Nresponse –Nbase) / (Nresponse + Nbase). The index range between -1 and +1, positive values correspond to an increase of calling after the stimuli (partner calls) compared to the baseline, negative value to an inhibition of calling, values close to 0 to maintenance of baseline calling (all the values are multiplied by 100 to aid readability). We set a threshold to avoid weak correlations to bias the results: if the number of calls within the time window considered did not reach 160 (i.e. one call for each bin) the index was not computed (reported as 0). (XLSX 31 kb)