How body size and microclimate determine when solar absorptivity matters for insect body temperature

Solar absorptivity increases Australian jewel beetles’ steady-state body temperature by up to 2.3°C on average in hot, calm conditions, but wind and radiation strongly modulate the effect.

• Why it matters: The net thermal impact of solar absorption is hard to predict because it depends on nonlinear interactions between insect traits and microclimate.
• What they did: Biophysical modelling quantified solar absorption effects for Australian jewel beetles across absorptivity 0.67–0.93, mass spanning more than 2 orders of magnitude, and shape under naturally co-occurring microclimatic conditions across Australia.
• The result: In transient simulations, effects were substantially damped on a one-minute timescale; across daylight in spring–early summer, the absorptivity effect averaged 0.36°C, reaching 5.69°C in the largest beetles under extreme high-radiation, low-wind conditions.