Final answer:
Competition in biology refers to the struggle between organisms for limited resources. It includes intraspecific competition within the same species leading to adaptations, and interspecific competition between different species that can result in one organism's advantage over another or in the specialization of both species.
Step-by-step explanation:
Competition is a fundamental ecological interaction where organisms vie for the same limited resources such as food, water, light, and space. This struggle can occur within the same species, which is called intraspecific competition, or between different species, known as interspecific competition. Intraspecific competition often leads to adaptations within a species, improving their chances of survival in their environment. For instance, when two trees of the same species compete for sunlight, the one able to grow taller to receive more light has a competitive advantage. Conversely, interspecific competition may result in one species outcompeting another, potentially leading to the other's extinction or both species evolving unique specializations to coexist. This process is famously exemplified by character displacement, where species develop specialized traits to utilize different resources when they inhabit the same area.