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Lower Cambrian vertebrates reported in Nature
the Online Nature extracts just listed the following:
>Lower Cambrian vertebrates from south China
>D-G. SHU, H-L. LUO, S. CONWAY MORRIS, X-L. ZHANG, S-X. HU, L. CHEN, J.
HAN, M. ZHU, Y. LI & L-Z. CHEN
>The first fossil chordates are found in deposits from the Cambrian period
>(545-490 million years ago), but their earliest record is exceptionally
>sporadic and is often controversial. Accordingly, it has been difficult to
>construct a coherent phylogenetic synthesis for the basal chordates. Until
>now, the available soft-bodied remains have consisted almost entirely of
>cephalochordate-like animals from Burgess Shale-type faunas. Definite
>examples of agnathan fish do not occur until the Lower Ordovician (475 Myr
>BP), with a more questionable record extending into the Cambrian. The
>discovery of two distinct types of agnathan from the Lower Cambrian
>Chengjiang fossil-Lagerstätte is, therefore, a very significant extension of
>their range. One form is lamprey-like, whereas the other is closer to the
>more primitive hagfish. These finds imply that the first agnathans may have
>evolved in the earliest Cambrian, with the chordates arising from more
>primitive deuterostomes in Ediacaran times (latest Neoproterozoic, 555 Myr
>BP), if not earlier.
not Dinosaurs, but - somewhat indirectly and long windedly - ancestral...
-- Neil Taylor "Creo Imaginem Mente"
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