How are niches influenced by competition?

The finches of the Galapagos Islands are a well-studied example. It is thought that a single population of finches migrated to the remote islands; no other birds were present on the recently formed volcanic islands; there were several niches available; distinct populations of finches carved out distinct niches.

With competition forcing them to find new niches and means of survival on the semi-desert islands, finches have been reduced in number to an estimated 13 subspecies on the islands. Among them are large beaked ground finches that can eat large seeds, medium and small beaked ground finches, and finches that eat cactus.

Competition influences niches by shaping the availability of resources and the distribution of species within an ecosystem. Intense competition can lead to resource partitioning, where species adapt to use different resources or occupy different niches to reduce direct competition. This can result in niche differentiation, where species evolve to occupy distinct ecological niches within the same habitat, allowing them to coexist despite competition for resources. Additionally, competition can drive evolutionary adaptations, leading to niche specialization and the development of unique traits or behaviors that enhance a species' competitive advantage within its niche. Overall, competition plays a significant role in shaping the structure and dynamics of ecological niches within ecosystems.