Prehistoric fish discovery in China


This video says about itself:

A Silurian placoderm with osteichthyan-like marginal jaw bones

27 Sep 2013

An exceptionally-preserved placoderm from the Silurian of China. Digital dynamic restoration of specimen IVPP V18620 (holotype of Entelognathus primordialis gen. et sp. nov.) showing the cheek complex, sclerotic ring, mandible, submandibular and gular series in external and internal views.

By Molly Michelson in the USA:

Fish Face!

September 27, 2013

Meet your distant relative, Entelognathus primordialis, possibly the first earthling with a face. Or at least a familiar face.

Entelognathus primordialis (where Entelognathus means “complete jaw”) is described this week in Nature. Discovered in a quarry in China, the remarkably well-preserved fossil is somewhat 3D, displaying a modern type of jaw.

E. primordialis is a placoderm, an early class of fish that lived 430 to 360 million years ago. These fish were covered with an armor of bony plates and gave rise to two later groups—bony fish and cartilaginous fish.

The evolution of jaws is one of the key episodes in the evolution of vertebrates, but the gap between jawed and jawless vertebrates is so large that it has been hard to work out the individual evolutionary steps in the transition. Min Zhu and his colleagues hope to make the link with E. primordialis.

The 419 million-year-old fish fossil has jawbone features previously restricted to bony fishes, but has the full body armor seen in placoderms. It would have been around 20 centimeters (eight inches) long.

Prior to this recent find, most scientists agreed that placoderms had no jaw and were more similar to the cartilaginous fish, like modern day sharks, while the bony fishes are believed to be our ancestors. According to Nature News:

Such fishes went on to dominate the seas and ultimately gave rise to land vertebrates.

In addition to facing off with placoderms, the new study puts cartilaginous fishes into a whole new light—perhaps they are even more evolved than previously thought.

About these ads

4 thoughts on “Prehistoric fish discovery in China

  1. Pingback: South Africa: world’s oldest fossil lamprey found | Dear Kitty. Some blog

  2. Pingback: Triassic fossil fish discovery in Switzerland | Dear Kitty. Some blog

  3. Pingback: Silurian fossils found in Canada | Dear Kitty. Some blog

  4. Pingback: Devonian era animals and plants | Dear Kitty. Some blog

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s