TY - JOUR
AU - Reed, Charles A.
AB - POLYPHYLETIC OR MONOPHYLETIC ANCESTRY OF MAMMALS, OR: WHAT IS A CLASS? CHARLES A. REED College of Pharmacy, University of Illinois, Chicago, Ill. Received January 25, 1960 A recent issue of EVOLUTION carried genetically based' he means "... arose two articles (Olson, 1959; Simpson, wholly from one of lower categorical 1959) on the origin of mammals. Olson level, as Class Mammalia from Order looked up, as it were, from the murky Therapsida." depths of the Pennsylvanian and saw the As matters stand at present, then, ongoing evolution of the Synapsida several different groups within the Class culminating in the late Triassic in several Mammalia (as commonly accepted) are lines which he could call mammals. related to each other only by descent Simpson adopted the opposite point of through several groups of therapsid rep­ view, and looked down the mammalian tiles. Such a concept of the meaning of evolutionary sequence from the end of 'Class' and of 'mammal' will be strange the Mesozoic. However, he arrived at to most zoologists, trained as they have the same time-level and the same con- been in the tradition of monophyletic elusion as did Olson: The mammals are descent of all members of any taxon. 
TI - POLYPHYLETIC OR MONOPHYLETIC ANCESTRY OF MAMMALS, OR: WHAT IS A CLASS?
JF - Evolution
DO - 10.1111/j.1558-5646.1960.tb03093.x
DA - 1960-09-01
UR - https://www.deepdyve.com/lp/oxford-university-press/polyphyletic-or-monophyletic-ancestry-of-mammals-or-what-is-a-class-CMLefoChCr
SP - 314
EP - 322
VL - 14
IS - 3
DP - DeepDyve
ER -