Impacts of Sea Lamprey Sex Ratio Variation Analysis based on L-V Model and P-P Model

As an important animal model for the study of biological evolution and disease, lamprey has attracted the attention of many scholars. Its variable sex ratio is also becoming the focus of studying because of the impact of ecological system. This paper utilizes mathematical method, and establishes the Lotka-Volterra Model to simulate the variations of the sex ratio among lamprey larvae populations. Additionally, Holling II function and Weak Alley Effect are adopted to establish a Predator-Prey Model of adult lampreys in three-tiered food chain, predicting the population dynamics of adult lamprey. The result of model simulation finds that low environmental capacity leads to a unexpectedly high ratio of male lampreys, which is up to 74.51% and proably causes population extinction. The study offers a novel insight into the interaction between ecosystems and fish species with variable sex ratios such as the lampreys.