Final answer:
Researchers use life tables to study mortality rates at different developmental periods and to explore hypotheses about the post reproductive period in humans. These studies include examining patterns in female fertility decline until menopause and investigating the biological and evolutionary significance of an extended post reproductive lifespan.
Step-by-step explanation:
Human Post reproductive Period Hypotheses: Researchers have formulated several hypotheses regarding the human post reproductive period, particularly focusing on the extended lifespan beyond the reproductive years. One of these hypotheses posits the importance of the life table, which is a tool that can help calculate mortality rates at various age intervals to understand survival patterns within a species. This approach could be utilized to test the proposition that mortality rates are extremely high during certain developmental periods—whether before or after sexual maturity is reached. In the context of female reproductive system aging, fertility peaks in the twenties and gradually diminishes until 35 years, after which it declines more rapidly until menopause—the cessation of the menstrual cycle due to the loss of ovarian follicles. The hypotheses around this period may include the evolutionary benefits of having postreproductive individuals in a population, such as the 'grandmother hypothesis' which suggests that older individuals can contribute to the survival of grandchildren, thus enhancing their own genetic legacy. The study of reproductive physiology, covering mechanisms of inheritance, hormonal control of reproduction, and the interplay between ovarian and menstrual cycles, also influences understanding of the postreproductive period. Specifically, the role of male and female reproductive hormones and the events associated with menopause are imperative components when constructing hypotheses regarding the decline in reproductive capabilities and the associated implications on overall mortality and health during the postreproductive years.