Relationships within the melanogaster species subgroup of the genus Drosophila ( Sophophora ). I. Inversion polymorphisms in Drosophila melanogaster and Drosophila simulans

Drosophila melanogaster from 67 collections have been analysed for their polymorphic inversions. Of the 53 inversions now known in this species 7 are widespread and 43 are endemic. The remaining 3 inversions may be widespread, but if so they are usually very rare. No X or fourth chromosome inversions were found. All the third chromosome inversions were paracentric, while six of the second chromosome inversions were pericentric. No inversions were found in D. simulans, of which 27 collections, from Africa, Europe, Australia and S. America, were studied.