NANFA-- Lampreys and hagfish and ostracoderms.

Hoover, Jan J WES (
Thu, 13 Jan 2000 14:04:18 -0600

There was an excellent recent article on the evolutionary importance of
jawless fishes:

Forey, P. and P. Janvier. 1994. Evolution of the early vertebrates.
American Scientist 82: 554-565.

It is well-written and has several photographs of fossil forms, and one
each of a living lamprey and hagfish, and some excellent drawings showing
jawless fishes in their formerly diverse glory. Also some neat color
diagrams fish brains and phylogenenetic trees.

Authors point out that there are conflicting theories on jawless fish
relatedness to each other and to jawed fishes. According to one viewpoint,
absence of jaws and paired fins, and similar gill pouches suggest that
lampreys and hagfishes are more closely related to each other than to jawed
fishes. According to another, similarities of the brain, kidney, and heart
suggest that lampreys are more closely related to jawed fishes than to

/"Unless stated otherwise, comments made on this list do not necessarily
/ reflect the beliefs or goals of the North American Native Fishes
/ Association"
/ This is the discussion list of the North American Native Fishes Association
/ To subscribe, unsubscribe, or get help, send the word
/ subscribe, unsubscribe, or help in the body (not subject) of an email to
/ For a digest version, send the command to
/ instead.
/ For more information about NANFA, visit our web page,