but what special difficulty is there in believing that it might profit the modified descendants of the penguin, first to become enabled to flap along the surface of the sea like the logger-headed duck, and ultimately to rise from its surface and glide through the air?
baina ba al da zailtasun berezirik sinesteko atal horiek onuragarri izan zekizkiekeela pinguinoaren ondorengo eraldatuei lehenik, dortoka-burudun ahateak bezala4, ur-azala hegoez astinduz itsasoan zehar ibiltzeko eta, azkenerako, azaletik gora egin eta airean zehar irristatzeko?