title: A new approach to sympatric speciation.
abstract: Sympatric speciation has always been a controversial issue. Recently, the debate has centred around the possibility that host race formation in phytophagous insects occurs as a first stage in this process. Now a new approach to host race formation - examining the population genetics of performance on alternative hosts - is challenging a major underlying assumption of this model. The evidence suggests that improved performance on one host is not generally accompanied by reduced performance on others.
authors.affiliation: Roger Butlin is at the Dept of Zoology, University College, PO Box 78, Cardiff CF1 1XL, UK.
authors.forename: R
authors.initials: R
authors.lastname: Butlin