Maintenance of the ‘atrophie gonadique’ character in Drosophila melanogaster: Theoretical models for natural and experimental evolution

✍ Scribed by G. Périquet

• Publisher: Springer Netherlands
• Year: 1979
• Tongue: English
• Weight: 880 KB
• Volume: 51
• Category: Article
• ISSN: 0016-6707
• DOI: 10.1007/bf00139496

✦ Synopsis

Analysis of the 'atrophie gonadique' polymorphism shows that its maintenance might be explained as the result of zygotic temperature dependent selection [in which elimination of (ag) is caused by sterility] compensated by an apparent gametic selection amplified by the (ag) advantage in drastic larval competition for food.

To analyse the role of temperature penetrance a frst evolutionary model was built. Simulations showed that a temperature of 20°C or temperatures that fluctuate as in nature, allow the (ag) character a relatively favorable situation which would assure its persistance at an observable frequency for over 16 years. Temperature protection creates a transient polymorphism compatible with the observed (ag) persistance in natural populations. Nevertheless, comparison with experimental evolution showed significant discrepancies.

Thus, simulations with a more general model including gametic-zygotic selection were performed and resulted in a better fit of the observed data. This model appears to correctly describe the (ag) polymorphism with a very weak advantage of the (ag) gametes, also showing how variations of gametic adaptive values might produce alternate phases of transient and stable polymorphisms.

The possibility that relatively simple rules may approximate fitness components as controlled by a complex genetic system is discussed.