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275dazu bisher keine Widerlegung) – zu den carnassial teeth gehören jedoch zwei:"The order Carnivora (from Latin carnis [flesh] and vorare [to devour]) includesall mammals that possess a pair of shearing carnassial teeth formed by theupper fourth premolar and lower first molar”. Bei der Cimolestes-cerberoides-Schere fehlt also zumindest die spezielle Ausbildung einer der zwei gegeneinanderbeweglichen Schneiden (viel mehr braucht man wohl zur optimalen Funktion einersolchen "Schere" nicht zu sagen – die Behauptung "…the upper forth premolarbegan…" einmal als richtig voraussetzt).Ein paar weitere Details zu Cimolestes cerberoides:(Nach J. David Archibald: A Study of Mammalia and Geology Across Cretaceous-Tertiary Boundary in Garfield County, Montana. University of CaliforniaPublications, Geological Sciences, volume 122, 1982, p. 162.) Man beachte, wievielematerialbedingte Unsicherheiten in dieser Beschreibung vorkommen:"Cimolestes cf. C. cerberoides Lillegraven, 1969C. cerberoides Lillegraven, 1969, p. 61Type. UA 2973, fragment of left side of skull with P 3-4 , M 1 , M 3 (Lillegraven, 1969, fig. 31-3).Type locality. Loc. KUA-I, Scollard Formation, Alberta.Referred specimens. LM 2 lacking parastylar lobe and part of the paracone, UCMP 117661Locality. UCMP loc V72207.Distribution. Scollard Formation, Alberta, and Hell Creck Formation. Montana (both Lancian).Description. One upper molar fragment, UCMP 117661, from the Hell Creek Formation is tentatively (indicated by "cf” 510 )referred to Cimolestes cf. C. cerberoides. The parastylar lobe is missing, but the indented ectoflexus and the well developed metastylarlobe suggest that the tooth is an M 2 . The paracone is also broken off near its base, but when present it was definitely larger and tallerthan the metacone. In both C. cerberoides and C. incisus the disparity in size between the paracone and metacone increases goingfrom M 1 through M 3 .Two weak characters favor a tentative assignment of this tooth to Cimolestes cf. C. cerberoides. First, as in C. cerberoides, theprotocone region is relatively less anteroposteriorly compressed than in C. incisus. The second character is size. Only the posteriorwidth of UCMP 117661 can be measured. This dimension (W-P = 4.32 mm) is very close to the mean posterior width of C.cerberoides (Lillegraven, 1969, table 13). The value is also within the range of the posterior width of C. incsus (Clemens, 1973, table2) but is at the extreme lower end.If this tentative referral of UCMP 117661 to Cimolestes cerberoides is correct, it constitutes a geographic range extension of thespecies.”Kenneth D. Rose kommentiert die paläontologische Situation zur Evolution derCarnivora in seinem Werk The Beginning of the Age of Mammals wie folgt (2006,p. 129) 511 ; man beachte Formulierungen wie (zunächst das sachlich fragliche)"general agreement”, dann "plausibly”, "suggested”, "may have”, "hypothesisraises the possibility”, "according to”, "might have”, "could have”, "Fox andYouzwyshyn […] postulated”, mit dem Ergebnis "the precise timing of the originof Carnivora is unknown” – wobei hinzuzufügen ist, dass nicht nur precise timingunbekannt ist, sondern die gesamte evolutionstheoretische Ableitung überhaupt:"Following the work of Lillegraven (1969) there has been general agreement that the teeth of bothcarnivorans and creodonts can be plausibly derived from those of Cretaceous Cimolestidae, such asCimolestes (Fig. 8.10). Hunt and Tedford (1993) suggested that Cimolestes is more closely related toCarnivora than to Creodonta and that different lineages of the genus may have given rise to the twofamilies of miacoids (Viverravidae and Miacidae). This hypothesis raises the possibility that the orderCarnivora is diphyletic and that the classic synapomorphy of the order, P 4 /M 1 carnassials, arose more510 "In biology, the abbreviation [cf.] has one additional use in open nomenclature: it denotes specimens or populations that resemble a knowntaxon, but differ in details; they thus may or may not refer to an undescribed taxon. For example, a cory catfish was once known as Corydoras cf.reynoldsi, meaning that it resembles but is not identical to typical Corydoras reynoldsi. In this particular case, it indeed turned out to be a newspecies, later described as Corydoras tukano.” Vgl. https://en.wikipedia.org/wiki/Cf. (Zugriff 1. 4. 2013)511 K. D. Rose (2006): The Beginning of the Age of Mammals. The John Hopkins University Press. Baltimore (428 pp.; Rose is Professor, Centerfor Functional Anatomy and Evolution Graduate Program, The John Hopkins University School of Medicine, Baltimore; also ResearchAssociate, National Museum of Natural History, Smithonian Institution and Carnegie Museum of Natural History.