Degree of high phenotypic plasticity in wild populations of Daphnia in early spring


Inducible defenses have been empirically known as defensive phenotypes that are triggered by predator kairomones. We hypothesized that morphological defense of wild Daphnia varies not only with predator density, but also with the predator regime in the field. We observed how the morphological defenses of two Daphnia species (D. ambigua and D. pulex) changed according to the population density in the water column at daytime of predatory insect larvae Chaoborus flavicans in Lake Fukami-ike, Japan, from February to July. In both Daphnia species, the inducible defense morphology was highly expressed in March and April. Its degree of expression decreased, and did not change with increases in predator density from May to July. These seasons are generally considered as when the number of the larvae and fish increases, and predation becomes more active due to their growth and breeding. We suggest that the degree of inducible defense of Daphnia is higher at the end of the overwintering season, when Chaoborus larvae began to inhabit the water column during the daytime and is constant in other seasons regardless of predators regime changes. Field observation of wild populations is important for understanding the seasonal changes in the morphology, and to provide more realistic explanations of phenomena in inducible defense.



PlumX Metrics


Download data is not yet available.
Original Articles
Inducible defense, morphological plasticity, phenotypic plasticity, predator-prey interaction, principal component analysis.
  • Abstract views: 838

  • PDF: 216
  • Supplementary: 76
  • HTML: 21
How to Cite
Nagano M, Doi H. Degree of high phenotypic plasticity in wild populations of Daphnia in early spring. J Limnol [Internet]. 2018Mar.21 [cited 2021May7];77(2). Available from: