adjacent" regions were designated arbitrarily on maps resulting 

 from the first set of observations, and then held constant for 

 all subsequent observations. Data were analyzed by contrasting 

 changes in the relative proportion of polyps with sweeper tentacles 

 on adjacent and non-adjacent regions of colonies. Adjacent 

 regions were consistently smaller than non-adjacent regions on 

 the same colonies (approximately a third of the size). Therefore, 

 comparison of the absolute number of polyps with sweepers between 

 adjacent and non-adjacent regions yields a conservative estimate 

 of their density on adjacent regions (i.e., when adjacent and non- 

 adjacent regions have equal numbers of polyps with sweeper 

 tentacles, adjacent regions actually would have greater densities 

 of sweeper tentacles than non-adjacent regions). 



RESULTS 



Figure 1 compares the number of polyps with sweeper tentacles 

 on: A) tissues adjacent to the M. annularis , and B) tissues not 

 adjacent to the M . annularis . The median and a quarter of the 

 range is plotted on this graph since these data were clearly non- 

 normal and sample sizes were small (7-8). There is a significant 

 correlation between the number of polyps with sweeper tentacles 

 on adjacent tissues and time after initiation of the experiment 



8- 



<D 

 Q. 

 CD 

 CD 6 . 



5- 



a- 



o 



CI. 



6 



c 



c 



CD 



"O 

 CD 



E 



3- 



1 



-1 20 27 44 60 



days after start of experiment 



FIGURE 1. For M. cavernosa , change 

 in number of polyps with sweepers on 

 regions that are adjacent (A) or non- 

 adjacent (B) to opponents (M. cavernosa ) 

 Vertical bars indicate quartile ranges. 



63 



