Two species of closely related swallows live on the same continent. the black swallow lives in coniferous forests, and the yellow swallow lives in deciduous forests. on an island where the black swallow has never been introduced, the yellow swallow lives in both coniferous and deciduous forests. explain this difference in observed yellow swallow habitats in terms of niches and interspecific competition.

These two closely related species have evolved to use the resources of an ecosystem in a different way, in order to be able to cohabit and coexist. Niche is an ecological term used to refer to the ecological roles of species in an ecosystem. In the same context, niche differentiation refers to the process by which competing species use the environment differently in a way that helps them to coexist. In addition, interspecific competition is another ecological term used to describe how individuals of different species compete for the same resources in an ecosystem. When individuals of these two species of swallows live on the same ecosystem, they compete against the resources (food and habitat) that are available in this habitat. Due to niche differentiation, they are able to coexist in the same ecosystem by limiting their habitat. 

The answer is a because it say when u add the h+ ions in the periodic table