Ichthyology: Background information when reading Run

Ichthyology

This article relates to Run

Ichthyology is the branch of zoology that studies fish. This includes skeletal fish, cartilaginous fish and jawless fish.

There are at least 25,000 fish species in existence. Each year, about 250 new species are discovered and described.

The largest species of fish known is theWhale Shark, which can grow to up to 50 feet in length and can weigh 15 tons or more.

There is much debate over which is the smallest known species of fish. One contender is the tiny carp-like Paedocypris progenetica, that grows to a maximum of about 10mm.

Another is the male Photocorynus spiniceps which grows to about 6 mm at maturity; but he is hampered in his claim by the overly-large female spiniceps that grows to a record-destroying 4.5cm!

Possibly the strongest claimant is the Stout Infantfish that grows to about 10mm but weighs less than one-millionth of a kilogram. Supporters of the Stout Infantfish claim it is the winner because game-fishing records are based on weight not height; thus they argue that weight is the key measurement criteria for identifying the world's smallest fish. Not that there's much game fishing to be had with this particular species, considering it would take half a million of them to achieve the equivalent weight of a one-pound trout!

Filed under Medicine, Science and Tech

This "beyond the book article" relates to Run. It originally ran in September 2007 and has been updated for the July 2008 paperback edition. Go to magazine.