A seed flying like a bullet: ballistic seed dispersal in Chinese witch-hazel (Hamamelis mollis OLIV., Hamamelidaceae).

ABSTRACT: The fruits of Chinese witch-hazel (Hamamelis mollis, Hamamelidaceae) act as 'drying squeeze catapults', shooting their seeds several metres away. During desiccation, the exocarp shrinks and splits open, and subsequent endocarp deformation is a complex three-dimensional shape change, including formation of dehiscence lines, opening of the apical part and formation of a constriction at the middle part. Owing to the constriction forming, mechanical pressure is increasingly applied on the seed until ejection. We describe a structural latch system consisting of connective cellular structures between endocarp and seed, which break with a distinct cracking sound upon ejection. A maximum seed velocity of 12.3 m s^-1, maximum launch acceleration of 19 853 m s^-2 (approx. 2000g)

SUBMITTER: Poppinga S 

PROVIDER: S-EPMC6731504 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature