Revista Chilena de Historia Natural 84 (4): 523-533, 2011
RESEARCH ARTICLE
Diet-induced developmental plasticity in life histories and energy metabolism in a
beetle
Adaptive phenotypic plasticity, has been recognized as an important strategy
by which organisms maximize fitness in variable environments, which vary through development. A disassociation among
stages should represent a null effect of the environment experienced during early ontogeny in the expression of adult traits.
Food quality greatly influences survival, development and reproduction in many arthropod herbivores. We examined the
effects of diet protein in physiological and life-history traits in the yellow mealworm beetle Tenebrio molitor
through ontogeny. We established four experimental treatments: Low Protein (LP), Low Protein Control (LPC), High
Protein (HP), and High Protein Control (HPC) with recently eclosioned larvae each. Individuals were maintained on the
same diet or transferred to the opposite diet for all pupae period and almost all adult period. Contrary to the expected, the
duration of life-cycle, larval growth rate and body mass in T. molitor were similar in diet treatments. We found
intra-individual trade-offs between environmental diet (rich or poor in protein content) during larval phase and egg number.
Larvae fed on a protein-deficient diet exhibited significantly higher respiratory rates than larvae fed on a rich protein diet.
Compensatory feeding could act in T. molitor larvae indicating differences in metabolism but not in growth
rate, body mass and life-cycle characteristics. Our results demonstrate the plasticity of reproductive and metabolic traits and
lifecycle characteristics of T. molitor and how changes that occur in relation to diet can have profound effects
on progeny and female fitness.
Key words:
CO<sub>2</sub> production, complex life-cycle, food quality, metabolism,
ontogeny
