The genus Aegilops represents the secondary gene pool of wheat. A better understanding of the germination behaviour of Aegilops species is important to improve their use in breeding programmes and strengthen their in situ/ex situ conservation. In this study, we investigated the germination behaviour of nine Aegilops species, five of them not yet investigated, under two alternating and two constant temperatures. Seed germination was higher than 60% in all temperature treatments and species. Alternating temperatures promoted higher germination rates in all the species and significantly enhanced seed germination in three species (Aegilops biuncialis, Aegilops geniculata and Aegilops neglecta), in comparison with constant temperatures. One of the rarest and least productive species in the genus (Aegilops uniaristata) displayed the highest germination. This study suggests that different (seed) regeneration strategies/niches occur across Aegilops species.