- LUNGFISHES - FISHES THAT BREATHE
- Subclass Dipnoi
The lungfishes have an almost complete fossil record
in Australia, including superb three-dimensional skulls of Devonian
age from New South Wales and Western Australia. This record tells
us lungfishes acquired the ability to breathe air independently
of other vertebrates and are therefore not considered ancestral
to the first four-legged land animals, the amphibians.
The story of lungfish evolution is one of frantic and rapid change
during the Devonian, the “dipnoan renaissance”, with
a much reduced rate of evolutionary change from the end of Carboniferous
Period to recent times. The three living lungfish genera occur
in Africa, South America and Australia, all formerly parts of
ancient Gondwana. Fossils of the Australian lungfish indicate
that this species has remained unchanged for at least 100 million
years, making it the most enduring vertebrate known on Earth.
(See Chapter 8.)
Summary by Dr. Irwin Haydock of the book entitled The Rise
of Fishes, 500 million years of evolution, by John A. Long, Johns
Hopkins University Press, 1995. (See Chapter 8)
If you would like to learn more about the evolution of fishes,
we recommend Long's excellent book. It's loaded with information,
well written and easy to understand.
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