2024美赛A题思路：资源可得性和性别比例Resource Availability and Sex Ratios_sex determination in lampreys

解析：解析传送

虽然一些动物物种存在于通常的雄性或雌性之外，但大多数物种都是雌雄同体。
基本上不是男性就是女性。虽然许多物种在出生时表现出1：1的雌雄比例，但其他
物种的雌雄比例偏离了平均值。这被称为适应性雌雄比例变异。举个例子来说，
美国短吻鳄巢内孵化蛋的温度会影响它们在不同温度下的雌雄比例。
出生时。
七鳃鳗的角色是复杂的。在一些湖泊栖息地，他们被视为寄生虫与一个
对生态系统有重大的影响，而七鳃鳗也是一些地区的食物来源。
世界，如斯堪的纳维亚半岛，波罗的海，和一些土著人民的太平洋
位于北美洲的西北部。
雌雄比例的海鳗可以根据外部环境的变化。海七鳃鳗成为
雄性或雌性取决于它们在幼虫阶段的生长速度。这些幼虫的生长
费率受食物供应情况的影响。在食物可利用性低的环境中，
增长率将较低，男性的比例可能达到约78%的人口。
人口数量。在食物更容易获得的环境中，雄性的百分比
据观察，约占人口的56%。
我们关注的是男女比例及其对当地条件的依赖问题，具体为
海七鳃鳗。海七鳃鳗生活在湖泊或海洋栖息地，并迁移到河流产卵。任务
是研究一个物种改变其雌雄比例的能力的利与弊
这取决于资源的可用性。您的团队应该开发和检查一个模型，以提供
对生态系统中产生的相互作用的见解。While some animal species exist outside of the usual male or female sexes, most species are
substantially either male or female. Although many species exhibit a 1:1 sex ratio at birth, other
species deviate from an even sex ratio. This is called adaptive sex ratio variation. For example,
the temperature of the nest incubating eggs of the American alligator influences the sex ratios at
birth.
The role of lampreys is complex. In some lake habitats, they are seen as parasites with a
significant impact on the ecosystem, whereas lampreys are also a food source in some regions of
the world, such as Scandinavia, the Baltics, and for some Indigenous peoples of the Pacific
Northwest in North America.
The sex ratio of sea lampreys can vary based on external circumstances. Sea lampreys become
male or female depending on how quickly they grow during the larval stage. These larval growth
rates are influenced by the availability of food. In environments where food availability is low,
growth rates will be lower, and the percentage of males can reach approximately 78% of the
population. In environments where food is more readily available, the percentage of males has
been observed to be approximately 56% of the population.
We focus on the question of sex ratios and their dependence on local conditions, specifically for
sea lampreys. Sea lampreys live in lake or sea habitats and migrate up rivers to spawn. The task
is to examine the advantages and disadvantages of the ability for a species to alter its sex ratio
depending on resource availability. Your team should develop and examine a model to provide
insights into the resulting interactions in an ecosystem.美赛、数学建模、美国大学生数学建模、美赛思路、美国大学生数学建模思路、2024美赛、2024美国大学生数学建模竞赛、2024美赛思路、2024美赛数据、2024美赛A题、2024美赛B题、2024美赛C题、2024美赛D题、2024美赛E题、2024美赛F题、 2024美赛数据、2024美赛论文、2024美赛解析、2024美赛思路、美国大学生数学建模竞赛思路、美赛解析、美赛免费思路