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305"The earliest member of the Caninae is the genus Leptocyon. This genus was adapted to mesocarnivory(moderate carnivorous adaptations intermediate between hypo- and hyper-carnivory). The genus is notonly the first, but also the only representative of the family for most of its history, ranging from EarlyOligocene until Late Miocene. The radiation of Caninae started when several ecological niches becameavailable again, due to the extinction of all small Borophaginae (Wang et al., 2004). During the earlystages of this radiation all major clades of living Canidae appeared (Tedford et al., 2001).”"…due to the extinction of all small Borophaginae”: Klingt evolutionstheoretischvielleicht plausibel – stimmt nur nicht ( – "few fox-sized borophagines remained”siehe Zitat unten; Cynarctos z. B. ist noch relativ klein, kleiner als unsererRotfuchs). Außerdem schaffen Freiräume ("several ecological niches") nichtautomatisch neue Gene, abgesehen davon, das eine ganze Anzahl großerBorophaginae die übrigen Nischen über Millionen Jahre noch weitgehend besetzthielt (Borophagus, Epicyon, Carpocyon und andere).Tedford et al. 2009, p. 5 zu den Unterschieden zwischen Borophaginae undCaninae (aus dem Abstract):"The Caninae diverged from the Borophaginae in the narrowing and elongation of the premolarsseparated by diastemata and placed in a shallow ramus and narrow muzzle. These latter features allowthe Caninae to be recognized in the fossil record as early as the beginning of the Oligocene (34 Ma) andconstitute evidence that they represent a monophyletic group.In striking contrast to the history of the Borophaginae, the Caninae remain confined to a closely similargroup of fox-sized species (Leptocyon spp.) throughout the Oligocene and showing very limitedcladogenesis into the end of the medial Miocene (12 Ma), a span that saw marked adaptive divergence inthe Borophaginae and the origin of all its major clades. By 12 Ma (beginning of the Clarendonian LandMammal age) few fox-sized borophagines remained and most of those held hypocarnivorus adaptations.At that point the Vulpini appear both as mesocarnivores (Vulpes spp.) and hypocarnivores (Metalopex spp.)reproducing, on a much smaller scale, the range of adaptations shown in the initial radiation of theBorophaginae.By the end of the Clarendonian (9 Ma) the first members of the tribe Canini appear. 580 ”Bevor wir uns weiteren Merkmalen zuwenden, die die Unterfamilie der Caninaevon den beiden übrigen Unterfamilien, Hesperocyoninae und Boraphaginae,trennen, kurz eine Definition des Begriffs "Synapomorphy”: "In cladistics, asynapomorphy or synapomorphic character is a trait that is shared("symmorphy") by two or more taxa and their most recent common ancestor,whose own ancestor in turn does not possess the trait. A synapomorphy is thus anapomorphy visible in multiple taxa, where the trait in question originates in theirlast common ancestor. The word "synapomorphy" is derived from the Greek wordsσύν, syn = with, in company with, together with; ἀπό, apo = away from; andμορφή, morphe = shape." 581Die diagnostic synapomorphies der Caninae beschreiben Tedford et al. 2009, p.13 wie folgt (Numerierung von mir):"The diagnostic synapomorphies for the subfamily consist of the following features (branching-point C inTedford et al., 1995: fig. 2, slightly modified by this study, fig. 1): [1] horizontal rami of the mandibleshallow and thin; [2] premolars narrow and elongate; [3] posterior cusplets on p2–p3 weak or absent;[4] P2–P3 and p2–p4 separated by short diastemata; [5] P4 slender, protocone small, anteriorcingulum reduced or absent; [6] m1 trigonid elongate (particularly paraconid); [7] paroccipitalprocess directed ventrally and fused with bulla.”580 Nach der Darstellung von Wang und Tedford (2008/2010, p.179) jedoch ein Million Jahre früher: Metalopex und Eucyon existiertendemnach etwa 1 Million Jahre gleichzeitig mit Leptocyon.581 http://en.wikipedia.org/wiki/Synapomorphy (Zugriff 22. 4. 2013)