Table 5. Pairwise mean comparison of Student t-statistic of IRV scores of 6 groups of 133 species tested.

	Teleosts	Elasmobranchs	Crustaceans	Bivalves	Cephalopods
Teleosts
Elasmobranchs	3.509**
Crustaceans	5.126**	5.879**
Bivalves	1.106	1.171	3.083**
Cephalopods	0.238	2.258*	2.739**	0.739
Gastropods	1.537	0.814	3.490**	0.309	1.084

** indicates high significance (p<0.001) and

* indicates significance (p<0.05). One-way ANOVA showed significant differences between groups at a 1% level.