Phenotypic response to different predator strategies can be mediated by temperature

Area of Science:

• Ecology
• Evolutionary Biology
• Environmental Science

Background:

• Temperature fluctuations impact species interactions and community stability.
• Antipredator responses are crucial for prey survival and are increasingly recognized as temperature-dependent.
• Understanding these responses is vital for predicting ecological dynamics under climate change.

Purpose of the Study:

• To investigate how temperature affects the phenotypic antipredator responses of the ciliate Paramecium caudatum.
• To determine if predator hunting strategy influences temperature-dependent antipredator responses.
• To quantify behavioral and morphological changes in P. caudatum under different temperature and predation regimes.

Main Methods:

• Utilized a high-throughput automated robotic monitoring system for precise tracking of P. caudatum behavior and morphology.
• Exposed P. caudatum to two predator types (Homalozoon vermiculare and Didinium nasutum) with distinct hunting strategies.
• Assessed responses across two temperature regimes (15°C and 25°C) over a 24-hour period.

Main Results:

• Swimming speed of P. caudatum changed with temperature but was not affected by predator presence.
• P. caudatum exhibited a significant temperature-dependent morphological response (elongation) to Didinium nasutum at 15°C, but not at 25°C.
• No significant morphological response was observed in the presence of the predator Homalozoon vermiculare.

Conclusions:

• Temperature significantly modulates prey morphological responses to predation, with effects contingent on predator hunting strategy.
• The findings highlight the complex interplay between temperature, predator behavior, and prey adaptation.
• Emphasizes the need to consider synergistic antipredator responses in ecological studies of environmental change.