Question

Which factors influence life history strategies? How are species classified on the basis of life history strategies?

Short answer

Life history strategies are influenced by environmental, physiological, and genetic factors. Species can be classified into r-selected and K-selected species based on these strategies. r-selected species exhibit rapid growth rates, early reproduction, numerous offspring with low survival rates, and low parental investment. In contrast, K-selected species exhibit slower growth rates, delayed reproduction, fewer offspring with higher survival rates, and high parental investment. Species may show a mix of r- and K-selected traits, depending on their environment and evolutionary history.

Step-by-step solution

Life History Strategies Factors

Life history strategies are the ways in which species allocate energy towards growth, reproduction, and survival. They are influenced by various factors, which can be categorized into: 1. Environmental Factors: These factors include the availability of resources, competition, predation, and environmental conditions such as temperature, moisture, and light availability. 2. Physiological Factors: These factors include an individual's metabolic rate, body size, and reproductive modes. 3. Genetic Factors: These factors determine the potential of an organism to develop certain traits or adapt to specific environmental conditions. Now that we have identified the factors influencing life history strategies, let's discuss how species are classified based on these strategies.

Classification of Species Based on Life History Strategies

Species can be broadly classified into two primary groups based on their life history strategies: r-selected species and K-selected species. 1. r-selected species: These species usually exhibit: - rapid growth rates - early reproduction - the production of numerous offspring with low survival rates - low parental investment - a high rate of population increase \( (r) \) - the ability to colonize new habitats rapidly Examples of r-selected species include insects like mosquitoes and plants like dandelions. 2. K-selected species: These species exhibit: - slower growth rates - delayed reproduction - lower numbers of offspring with higher survival rates - high parental investment - a stable population size near carrying capacity \( (K) \) - the ability to compete effectively for limited resources Examples of K-selected species include larger animals like elephants, whales, and humans. It's essential to remember that the classification of species into r-selected and K-selected species is based on a continuum of life history traits and strategies. Species may show a mix of r- and K-selected traits, depending on their environment and evolutionary history.