FISHERY BULLETIN: VOL. 85, NO. 1 

 Table 1 .—Summary of life history information for the 10 shore fish species used in the analysis. 



histochemical staining have been described else- 

 where (Waples 1986). The 26 enzymes and proteins 

 surveyed were acid phosphatase, aconitate hydra- 

 tase, adenosine deaminase, adenylate kinase, alcho- 

 hol dehydrogenase, aspartate aminotransferase, 

 creatine kinase, esterase (a-naphthyl acetate), 

 fumarate hydratase, glucose-6-phosphate dehydro- 

 genase, glucosephosphate isomerase, glutamate 

 dehydrogenase, glyceraldehyde-phosphate dehydro- 

 genase, glycerol-3-phosphate dehydrogenase, 

 L-iditol dehydrogenase, isocitrate dehydrogenase, 

 lactate dehydrogenase, malate dehydrogenase, man- 

 nosephosphate isomerase, phosphoglucomutase, 

 phosphogluconate dehydrogenase, peptidase (leucyl- 

 tyrosine; leucylglycyl-glycine), superoxide dismu- 

 tase, umbelliferyl esterase, xanthine dehydrogenase, 

 and general muscle proteins. Presumptive gene loci 

 for which any variant alleles were detected were 

 surveyed in all individuals. Loci for which only a 

 single allele had been identified after sampling at 

 least 20 individuals in each population were con- 

 sidered to be monomorphic and were not surveyed 

 further in that species. 



Wright's Fgx was computed for each polymorphic 

 locus in each species by the method of Weir and 

 Cockerham (1984). Fgr values (0 < ^5,^ < 1) in- 

 dicate the proportion of total variance in allele fre- 

 quencies attributable to differences between (as 

 opposed to within) populations. Workman and Nis- 

 wander's (1970) test was used to identify Fg^ 

 values significantly larger than zero. Data for all 

 presumptive gene loci resolved in each species were 



combined in an index of overall genetic differentia- 

 tion (Nei's [1972] genetic distance (Z))), which pro- 

 vides a direct means of comparing levels of genetic 

 divergence between pairs of populations. D is the 

 negative natural logarithm of genetic similarity (/), 

 which is essentially the proportion of genes shared 

 by two populations. 



To determine whether similar patterns of popula- 

 tion structure occur in several species, D values for 

 each pair of localities (or the mean D values for each 

 locality) were ranked within each species. The 

 resulting matrix of rankings was evaluated for re- 

 curring patterns (departure from randomness) by 

 Friedman's method for randomized blocks (Sokal 

 and Rohlf 1981), which computes a statistic that is 

 a chi-square variate with 6-1 degrees of freedom: 



6 o 



4_,^ = [il2l{ab[b +1])) I (Ii2y)2] - 3a(fe + 1) 



(1) 



where a = number of rows (species, in this case), 

 b = number of columns (localities, or pairs of local- 

 ities), and Rij is the ranking of the i^^ locality (or 

 pair of localities) for the j*^ species. 



To identify species that exhibit anomalous pat- 

 terns of genetic differentiation, a jackknife pro- 

 cedure was used, the rankings of localities (or pairs 

 of localities) for each species being compared with 

 the overall ranking computed for all the other 

 species combined. Spearman's rank-order correla- 

 tion coefficient (rj was used to determine the 



