Final answer:
Lifetime reproductive success (LRS) is influenced by individual health, number of mating partners, and parental care investment. Life history strategies, which determine energy allocation for growth, maintenance, and reproduction, play a crucial role in shaping these factors. High investment in parental care usually means fewer offspring, improved offspring survival, and increased relative fitness of those offspring.
Step-by-step explanation:
Lifetime reproductive success (LRS) depends on a combination of factors that contribute to an organism's ability to survive and reproduce efficiently. These include a) individual health, ensuring the organism is physically capable of reproduction; b) the number of mating partners, which may increase the likelihood of successful reproduction; c) parental care investment, as there is often an inverse relationship between the number of offspring and the amount of care each receives, affecting their survival and development. A high parental care investment often means having fewer offspring, which reduces the likelihood of rapid population increases but increases the individual survival and health of the offspring.
Life history strategies, which are patterns of living in which species partition energy for growth, maintenance, and reproduction, strongly influence LRS. These strategies, which arise through natural selection, impact how and when organisms reproduce and how much care they provide to their progeny. Parental care investment, for example, can range from none at all, leading to many offspring with low survival rates, to substantial, resulting in fewer offspring who are more likely to survive to adulthood.
Ultimately, the relative fitness of an organism within its environment is a combination of these factors and will influence its overall reproductive success throughout its lifetime.