Table 1.

Mean (±s.d.) of call parameters for each species, measured in terms of matrix columns or rows. (See text for description of how calls were generated. The values for species A were those in the initial generation and are therefore the parameters of the ‘ancestral A’ call. The call parameters of A, but not B or C, were allowed to evolve. See figure 1 for contrast of evolved A calls versus the ancestral A call.)

call parameter	species
A	B	C
call duration (cols.)	62.6 (7.9)	9.1 (0.7)	62.4 (5.0)
inter-call interval (cols.)	72.0 (1.7)	64.8 (0.9)	87.6 (4.7)
call pulse rate (pulses col−1.)	0.05 (0.01)	0.42 (0.05)	0.34 (0.02)
dominant frequency (rows)	15.6 (1.2)	18.5 (1.2)	18.4 (1.5)