Of the periods listed below, which one is the earliest period when ost

1.	Of the periods listed below, which one is the earliest period when ostracoderms, the jawless and finless fishes, appeared?(a) Devonian period(b) Cambrian period(c) Carboniferous period(d) Silurian period
Answer» Answer is : (b) Cambrian period The class Ostracodermi is represented by the fossil vertebrates of late Cambrian period. The earliest known vertebrates to appear in fossil record were jawless primitive fish-like animals collectively called ostracoderms. These animals resembled the present day cyclostomes (lampreys and hagfishes) in many respects.

Of the periods listed below, which one is the earliest period when ostracoderms, the jawless and finless fishes, appeared?(a) Devonian period(b) Cambrian period(c) Carboniferous period(d) Silurian period

Answer»

Answer is : (b) Cambrian period

The class Ostracodermi is represented by the fossil vertebrates of late Cambrian period. The earliest known vertebrates to appear in fossil record were jawless primitive fish-like animals collectively called ostracoderms. These animals resembled the present day cyclostomes (lampreys and hagfishes) in many respects.

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Of the periods listed below, which one is the earliest period when ostracoderms, the jawless and finless fishes, appeared?(a) Devonian period(b) Cambrian period(c) Carboniferous period(d) Silurian period

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