Have you ever reached for a bag of chips at the same moment as another shopper? These small moments of competition reflect a bigger ecological puzzle: Why doesn’t one species grab every resource for itself?
Resources such as sunlight, water, and nutrients form part of what's called a species’ niche—which includes all the requirements a species needs to thrive, as well as how it affects other species around it. Think of the resource portion of a niche as a shopping list. When two species have identical lists, competition in nature’s grocery store can be fierce. But when their lists differ, even slightly, both species have a better chance of sticking around.
Researchers tested this idea with a computer model of two species sharing resources. Their “digital organisms” could adjust two things: which resources they targeted, and how efficiently they used them. The team then widened or narrowed the virtual grocery store to mimic habitat variety.
The simulations tell a clear story. In broad environments, packed with resource options, each species slides into its own spot in niche space. Overlap shrinks, much like shoppers drifting into different aisles of a well-stocked market, and both species survive. In narrow environments, where choices are few, overlap is unavoidable. One species may soon edge the other out.
These results explain why richer habitats usually support more life. Extra resource variety creates extra elbow room in niche space. Conservation that protects or restores that variety therefore safeguards biodiversity. Think of it as restocking nature’s shelves so every species can grab its favorite brand—and avoid those awkward collisions in the aisle.
A special thanks goes to Jennifer Lau, Indiana University, for reviewing today's episode. This script was written by Hongxi Li as part of Dr. Heather Reynolds’ class Z620 Ecological Niche Service-learning
Further Reading
Pastore, A. I., G. Barabás, M. D. Biller, M. M. Mayfield, and T. E. Miller 2021. The evolution of niche overlap and competitive
Differences. Nature Ecology & Evolution 5:330-337.