71 



Internal constraints (Figs. 4 and 14, and Tab. 4) 



The various alternative ingroup relationships tested in this study likewise all resulted in 

 cladograms that were longer than the overall solution (Tab. 4). The increases were again 

 virtually negligible, with most amounting to an increase in length of less than 0.72% (506 

 extra steps or eight extra corrected steps). The constraints of a monophyletic Phoca (both 

 sensu stricto and Burns & Fay 1970) were accommodated with minimal amounts of extra 

 homoplasy in particular. Surprisingly, not even the disruption of one of the most strongly 

 supported nodes in the overall solution, that of a monophyletic Phocidae, produced a 

 tangibly longer solution. Only the very specific constraints of "de muizon" and "wyss" 

 and, to a lesser degree, those requiring a monophyletic Cystophorinae ("three subfamily" 

 and "cystophorinae") yielded noticeably longer solutions (but still well under a 5% 



Table 4: Summaries of searches of the inversely weighted data matrix with certain topological 

 constraints of alternative ingroup relationships imposed (see Fig.4). MPT = most parsimonious trees. 

 Bootstrap frequencies for the desired monophyletic group are given whenever possible. When a 

 constraint tree imposes multiple monophyletic groups, the bootstrap frequency indicated is that of the 

 least supported major clade (indicated by an asterisk). 



V^UllollalllL L1CC 



Absolute Extra steps relative 



No. 



Bootstrap analysis 





length 



to overall solution 



of 



frequency 



(%) 







(absolute / corrected) 



MPT 







At family level 













- (not) phocidae 



70340 



(+506 / +8) 



2 







At subfamily level 













- (not) two subfamilies 



70028 



(+194 / +3) 



1 







- three subfamilies 



70779 



(+945 / +14) 



4 



3.00* 



« 1)* 



- cystophorinae 



70779 



(+945 / +14) 



4 



3.00 



« 1) 



- (not) monachinae 



70028 



(+194 / +3) 



1 







- (not) phocinae 



70048 



(+214 / +4) 



9 







Within Monachinae 













- Lobodontini 



70283 



(+449 / +7) 



1 



50.55 



(5) 



- (not) monachus 



70279 



(+445 / +7) 



2 







Within Phocinae 













- erignathus sister 



70140 



(+306 / +5) 



2 







- relaxed Burns & Fay 



69991 



(+157 / +3) 



3 



44.33 



(4) 



- strict Burns & Fay 



70041 



(+207 / +3) 



1 



64.06* 



(6)* 



- phoca 



69892 



(+58 / +1) 



1 



64.06 



(6) 



Within Phocinae 













- de Muizon 



71831 



(+1997 / +29) 



1 







- Wyss 



72406 



(+2572 / +38) 



1 







Miscellaneous 













- unweighted 



70048 



(+214 / +4) 



2 



314.00* 



(31)* 



- condense 



70453 



(+619 / +9) 



5 



44.33* 



(4)* 



