Sono magri ed agili e hanno una caratteristica che li contraddistingue: a 12 anni sono, o meglio erano, completamente sdentati. Di chi si tratta? Di piccoli dinosauri, noti col nome "Limosauro", di cui sono stati trovati resti in Cina.
Questi esemplari hanno vissuto 160 milioni di anni fa e, stando ai risultati pubblicati sulla rivista Science, questa trasformazione ha permesso loro di diventare erbivori. Alla nascita, infatti, avevano una dentatura che dava la possibilità di nutrirsi di carne, ma crescendo la perdevano completamente modificando quindi le loro abitudini in termini di cibo.
"Questa scoperta è importante per due ragioni'', spiega il co-autore dello studio James Clark, paleontologo della George Washington University. ''Innanzitutto è molto raro trovare una serie di esemplari di dinosauro che vanno dalla nascita all'età adulta. In secondo luogo, questo inusuale e drastico cambiamento anatomico indica un'importante variazione nella dieta dall'adolescenza all'età adulta", ha aggiunto. Questo fenomeno è presente anche in animali moderni, come ad esempio l'ornitorinco.
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