Influence of food on morphological characteristics of Daphnia galeata (Cladocera, Daphniidae) from Lake Baikal

Abstract

The study shows the influence of feeding conditions on morphological characteristics of Daphnia galeata (Sars, 1863) in different areas of Lake Baikal. At high food concentrations and in the absence of invertebrate predators of the species Leptodora kindti, the daphnids have a large body size, low helmets and short tail spines. At low food concentrations, crustaceans with small-sized shells, poorly developed helmets and tail spines dominate. In the presence of the predators, an abrupt shift of adaptive variation occurs: at low food concentrations, the crustaceans have a large body size, and at high ones, small adult daphnids with well developed protective patterns dominate.