Geographic variation in the growth rates ofLittorina littoreaandL. saxatilis

✍ Scribed by S. Behrens Yamada

• Book ID: 104756559
• Publisher: Springer-Verlag
• Year: 1987
• Tongue: English
• Weight: 492 KB
• Volume: 96
• Category: Article
• ISSN: 0025-3162
• DOI: 10.1007/bf00397970

✦ Synopsis

The two intertidal grazers Littorina littorea and L. saxatilis occupy extensively overlapping distributions on both sides of the Atlantic. Morphological, electrophoretic and physiological evidence suggests that the direct developer L. saxatilis is more geographically differentiated than the planktonic developer L. littorea. This hypothesis was tested by collecting both species in 1980 and 1981 from three geographically separated beaches in Massachusetts, USA, marking them, and releasing them in two of the sites. Individuals from all three L. littorea populations, grown at a common site, tended to grow at similar rates, while L. saxatilis exhibited consistent population differences in individual growth. This study supports the view that L. saxatifis achieves its broad geographic distribution via locally adapted ecotypes, while L. littorea achieves its distribution by individual physiological plasticity.