Junchang LĂź, David M. Unwin, Xingsheng Jin, Yongqing Liu and Qiang Ji
darmowy pdf => http://rspb.royalsocietypublishing.org/ ... l.pdf+html
abstract
luĹşny news:The fossil record is a unique source of evidence for important evolutionary phenomena such as transitions between major clades. Frustratingly, relevant fossils are still comparatively rare, most transitions have yet to be documented in detail and the mechanisms that underpin such events, typified by rapid large scale changes and for which microevolutionary processes seem insufficient, are still unclear. A new pterosaur (Mesozoic flying reptile) from the Middle Jurassic of China, Darwinopterus modularis gen. et sp. nov., provides the first insights into a prominent, but poorly understood transition between basal, predominantly long-tailed pterosaurs and the more derived, exclusively short-tailed pterodactyloids. Darwinopterus exhibits a remarkable ‘modular’ combination of characters: the skull and neck are typically pterodactyloid, exhibiting numerous derived character states, while the remainder of the skeleton is almost completely plesiomorphic and identical to that of basal pterosaurs. This pattern supports the idea that modules, tightly integrated complexes of characters with discrete, semi-independent and temporally persistent histories, were the principal focus of natural selection and played a leading role in evolutionary transitions.
Opisano nowego pterozaura z Ĺrodkowej bÄ dĹş późnej jury Chin, Darwinopterus modularis gen. et sp. nov., ktĂłry wypeĹnia morfologicznÄ lukÄ pomiÄdzy bazalnymi, w wiÄkszoĹci dĹugoogonowymi pterozaurami, a zaawansowanymi, wyĹÄ cznie krĂłtkoogonowymi pterodaktylami. Nowy rodzaj wykazuje siÄ niezwykĹÄ kombinacjÄ cech: czaszka i szyja sÄ typowe dla pterodaktyli, posiadajÄ liczne zaawansowane cechy, podczas gdy reszta szkieletu jest niemal kompletnie plezjomorficzna i identyczna z tÄ u bazalnych pterozaurĂłw. Nowo opisany takson pokazuje, Ĺźe u pterozaurĂłw wyjĹciowych dla pterodaktyli nastÄ piĹa najpierw modyfikacja czaszki, a dopiero później kluczowe zmiany w aparacie lotnym. Darwinopterus jest taksonem siostrzanym do pterodaktyli, tworzÄ c z nimi klad Monofenestrata.