Reptiles and herbivory

reptiles’, often treating them as ‘reptiles’ irk comparative discussions. While this will offend the devout cladist, it has some ration-

ale, as primitive synapsids display characters similar to those of the earlier members of the reptiles and are recently enough diverged from their reptilian sistergroup that fb>Li, .a... ,3ikA amlc8 ykid useful comparative information. By the later Permian, however, the two clades are sufficiently distant in their heritage that comparisons of synapsid and erbivores potentially serve rather than to illuminate ev~~~~t~onary patterns within reptiles. In particular, this approach obscures comparative differences that mighl elucidate the puzzle of why synapsid herbivores were initially so st~cessful in the Permian ranrdearly Triassic kfore crding the ground to reptilian rbymclaosaurs and dinosaurs in the later Triassic. What nnrrg~ from lhis overview is that lOlr iMWp8ay bktWef31 plalnl id reptilian krbivore has nsot been a story of continuok~4y incre;lsinfg efficiency. but rather a mo= saicl Some Late Permian and Triassic herb& vores possess a~a~~~tio~s

of tooth structure,

jaw strength and the potential for a griacling jaw motion that arc as s~~~b~st~catedas those observed in Late Cretaceous and Tertiary herbivores.

Yet these gave way to other

of lkc>rbivores depends org;knismal characters \~~rc~!Wilance.

or-

upon the totality of and environmental

ucpt 01 GeologKYrl Sclencr~~, University of Cal~forfi~a. SanlR E3tlrlXkn.3. CA ‘E%lOfi. USA