AskBiography Logo   Latest News  Follow Us on Twitter  Follow Us on Google Buzz  Became Fan - Facebook  Subscribe to RSSRSS   Bookmark and Share

     Home | time scale | Devonian

The Devonian is a geologic period and system of the Paleozoic Era spanning from the end of the Silurian Period, about 416.0 ± 2.8 Mya (million years ago), to the beginning of the Carboniferous Period, about 359.2 ± 2.5 Mya . It is named after Devon, England, where rocks from this period were first studied.

During the Devonian Period the first ray finned and lobe-finned bony fish evolved. The pectoral and pelvic fins of lobe-finned fish evolved into legs as they started to walk on land as tetrapods around 397 Ma. Various terrestrial arthropods also became well-established.

The first seed-bearing plants spread across dry land, forming huge forests.

In the oceans, primitive sharks became more numerous than in the Silurian and the late Ordovician. The first ammonite mollusks appeared. Trilobites, the mollusc-like brachiopods, as well as great coral reefs were still common. The Late Devonian extinction severely affected marine life.

The paleogeography was dominated by the supercontinent of Gondwana to the south, the continent of Siberia to the north, and the early formation of the small supercontinent of Euramerica in between.

Warning: simplexml_load_file( [function.simplexml-load-file]: failed to open stream: HTTP request failed! HTTP/1.0 410 Gone in /home/askbio/public_html/index_bio.php on line 257

Warning: simplexml_load_file() [function.simplexml-load-file]: I/O warning : failed to load external entity "" in /home/askbio/public_html/index_bio.php on line 257

Fatal error: Call to a member function children() on a non-object in /home/askbio/public_html/index_bio.php on line 260