Table 2. Mean individual swimming distances of the 6 fish that were present in all three treatments and mean area usage of the complete groups of the cave (a) and the surface mollies (b).

The area usage indicates the percentage of squares visited in a 4 × 4 grid.

	(a) Cave molly		(b) Surface molly
Treatment	individual swimming distance (cm)	group area usage	individual swimming distance (cm)	group area usage
G12a	662	100%	355	97%
G6	624	98%	256	78%
G12b	572	100%	320	100%