gaika
08.01.10, 18:47
Nie wiem na jaki to temat(może patriotyzm i duma narodowa, polska
flaga osadzona w skamielinie, prawie powstanie dla odmiany wygrane),
ale to zupełnie fascynujące skąd i jak przybywamy. Wszyscy o
tym piszą i trąbią, ale w Naturze wygląda piękniej.
Tetrapod trackways from the early Middle Devonian period of Poland
The fossil record of the earliest tetrapods (vertebrates with limbs
rather than paired fins) consists of body fossils and
trackways. The earliest body fossils of tetrapods date to the Late
Devonian period (late Frasnian stage) and are preceded by
transitional elpistostegids such as Panderichthys and Tiktaalik that
still have paired fins. Claims of tetrapod trackways
predating these body fossils have remained controversial with regard
to both age and the identity of the track makers. Here
we present well-preserved and securely dated tetrapod tracks from
Polish marine tidal flat sediments of early Middle
Devonian (Eifelian stage) age that are approximately 18 million
years older than the earliest tetrapod body fossils and 10
million years earlier than the oldest elpistostegids. They force a
radical reassessment of the timing, ecology and
environmental setting of the fish–tetrapod transition, as well as
the completeness of the body fossil record.
docs.google.com/gview?a=v&pid=gmail&attid=0.4&thid=1260da237fe87102&mt=application%
2Fpdf&url=http%3A%2F%2Fmail.google.com%2Fmail%2F%3Fui%3D2%26ik%
3D7b4c760f7d%26view%3Datt%26th%3D1260da237fe87102%26attid%3D0.4%
26disp%3Dattd%26realattid%3Df_g46v407e3%
26zw&sig=AHIEtbSGkkk7LHf0MREBGxT9D7Huz7SbHw
