Intra- and interspecific sequence variation in a portion of the mitochondrial ND6 gene in cuckoos

Abstract

A 474 base pair segment of the NADH dehydrogenase subunit 6 (ND6) mitochondrial gene was sequenced for four cuckoo species (family Cuculidae). To assess the potential of this little-studied gene for intra- and interspecific genetic analyses, we examined sequence variation between (1) individuals from sympatric populations of the Common Cuckoo (Cuculus canorus canorus) collected in Great Britain, (2) two subspecies of Common Cuckoo (C. c. canorus and C. c. telephonus) collected at the geographical extremes of this species' range, and (3) four representative Cuculids: the Common Cuckoo, the Rusty-breasted Cuckoo (Cacomantis sepulcralis), the Fan-tailed Cuckoo (Cacomantis flabelliformis), and Klaas's Cuckoo (Chrysococcyx klaas). Although we found little genetic divergence at the intraspecific level, the substantial amount of interspecific sequence variation indicated that ND6 may be most useful in resolving evolutionary relationships between cuckoo species rather than within species.