Limited supply of at least one resource (such as food, water, and territory) used by both usually facilitates this type of interaction, although the competition may also exist over other 'amenities', such as females for reproduction (in case of male organisms of the same species).
Begrænsningen af mængden af mindst en resurse (såsom mad, vand og territorium), som anvendes af begge forøger normalt denne type interaktion, selvom konkurrencen også kan eksistere i forhold til andre "bekvemmeligheder", såsom hunner til reproduktion (i tilfælde af mandlige organismer af samme art).