An underdescribed sound change in Germanic is the shift of initial kl and gl to tl and dl respectively. Though not widely known, KL > TL has occurred more than once in the history of Germanic. Relevant phonetic factors include coarticulation and perceptual similarity. A third structural factor in Germanic and elsewhere is a pre-existing TL gap. KL > TL gives rise to common TL clusters, though, under many phonological analyses, TL clusters are disfavored or marked. Typological comparison suggests that TL clusters are not marked, but that contrasts between KL and TL are disfavored.
©Walter de Gruyter