Seasonal synchronicity and stage-specific life-cycles

In his study on Catops nigricans (Coleoptera: Leiodidae), Topp [1] (W. Topp, Selection for an optimal monovoltine life-cycle in an unpredictable environment: Studies on the beetle C. nigricans Spence. Oecologia 84: 134–141 (1990).) observed that the times of eclosion and oviposition of a population of this European beetle are tightly synchronized to the local seasonal environment. Topp proposed that the key mechanism producing such synchrony is the developmental response that individuals exhibit to seasonal fluctuations of temperature and light at discrete stages of their life cycle. Here, an individual-level model of the C. nigricans life cycle is constructed and parameterized with the complete set of Topp's stage-specific development data. Seasonal variations of temperature and light are replicated by sinusoidal functions of time. Simulations are carried out to investigate the temporal behavior of lineages (generated from an arbitrary cohort) exposed to these periodic environmental variations over several generations. Our results support the hypothesis that stage-specific development in a periodic environment produces a powerful mechanism by which life-cycle synchronization can occur