The Dipnoi first appeared in the Early Devonian Epoch (about 419.2 million to 393.3 million years ago), and the extant species occur in rivers and lakes in Africa, South America, and Australia.

What did the lungfish evolve from?

It is generally agreed that their ancestors were lobe-finned fish. What is not agreed is how close either of the extant groups of lobe-finned fish, lungfish or coelacanths, is to the actual ancestor of the tetrapods. The soft anatomy of living lungfish shares many similarities with that of living amphibians.

Do lungfish prove evolution?

Lungfish are of great interest to evolutionary biologists, because they can provide key information on the pre-adaptations, changes in body plan and physiology and molecular changes that enabled the transition from aquatic to land life.