Fig. 2.

Species-specific temperature-size responses (% change in mass per °C) expressed as a function of the organism size (dry mass) in aquatic (marine and freshwater) and terrestrial environments, including both uni- and multicellular organisms. Terrestrial species have a significant positive regression (PCM = −1.72 + 0.54 × log₁₀DM, R² = 0.15, df = 53, P < 0.01, solid line); aquatic species have a significant negative regression (PCM = −3.90 – 0.53 × log₁₀DM, R² = 0.14, df = 53, P < 0.01, thick dashed line). Because there is no significant change in the temperature-size response with mass in unicellular species, the mean response is given by the thin dashed horizontal line (−1.80%°C⁻¹).