Inducible defences as key adaptations for the successful invasion of Daphnia lumholtzi in North America?

AUTOR(ES)

Engel, Katharina

FONTE

The Royal Society

RESUMO

The mechanisms underlying successful biological invasions often remain unclear. In the case of the tropical water flea Daphnia lumholtzi, which invaded North America, it has been suggested that this species possesses a high thermal tolerance, which in the course of global climate change promotes its establishment and rapid spread. However, D. lumholtzi has an additional remarkable feature: it is the only water flea that forms rigid head spines in response to chemicals released in the presence of fishes. These morphologically (phenotypically) plastic traits serve as an inducible defence against these predators. Here, we show in controlled mesocosm experiments that the native North American species Daphnia pulicaria is competitively superior to D. lumholtzi in the absence of predators. However, in the presence of fish predation the invasive species formed its defences and became dominant. This observation of a predator-mediated switch in dominance suggests that the inducible defence against fish predation may represent a key adaptation for the invasion success of D. lumholtzi.

Documentos Relacionados

• First record of Daphnia lumholtzi (Sars, 1885), exotic cladoceran, in São Paulo State (Brazil)
• What does the field of International Relations look like in South America?
• Cryptic invasion by a non-native genotype of the common reed, Phragmites australis, into North America
• 21. The Findings in North America
• Human cytotrophoblasts adopt a vascular phenotype as they differentiate. A strategy for successful endovascular invasion?