Interspecific interaction is a biological concept within community ecology, or the study of the organization and functioning of the populations of species living within a particular habitat. As a part of the web of communities, interspecific interaction refers to when two unrelated species have certain types of interactions.http://www.britannica.com/EBchecked/topic/129392/community-ecology/70602/Interspecific-interactions-and-the-organization-of-communities# Examples of interactions can include pollination, nesting and feeding.http://www.youtube.com/watch?feature=player_embedded&v=NRqEYroujqA

Three types of interspecific interactions include mutualism, commensalism and parasitism. These interactions can benefit both species, neither benefit nor harm either species or benefit only one of the species while harming the other.http://www.youtube.com/watch?feature=player_embedded&v=NRqEYroujqA The organization and stability of biological communities result from the mix of these types of interactions.http://www.britannica.com/EBchecked/topic/129392/community-ecology/70602/Interspecific-interactions-and-the-organization-of-communities# 

Mutualism occurs when two unrelated species (species A and B) both benefit from a specific interaction (+,+). Often in mutualistic interactions, one species acts as the host while the other is the "visitor." One example involves bees and flowers - bees benefit from pollination because they need the flower's nectar to survive, while flowers benefit from pollination because it allows them to reproduce.http://www.youtube.com/watch?feature=player_embedded&v=NRqEYroujqA

The benefits that are received from these interactions can vary from one species to another. A species can gain food, protection from enemies, a nesting site or a combination of benefits.http://www.britannica.com/EBchecked/topic/129392/community-ecology/70602/Interspecific-interactions-and-the-organization-of-communities#

Commensalism occurs when species A benefits from the interaction, but species B remains neutral (+,0). Species B, then, does not benefit from nor is harmed by the interaction. In commensal interactions, species A may depend on species B for food, shelter, support, transport or a combination of all of these.http://www.britannica.com/EBchecked/topic/129392/community-ecology/70602/Interspecific-interactions-and-the-organization-of-communities# 

An example of commensalism is with anemone fish (clownfish) and sea anemone. Anemone fish, whose scales are immune to the anemone's lethal sting, can seek protection from enemies within the tentacles of the anemone.http://animals.nationalgeographic.com/animals/fish/clown-anemonefish/ The anemone, however, does not really benefit from this interaction.http://www.youtube.com/watch?feature=player_embedded&v=NRqEYroujqA

Parasitism is an interspecific interaction where species A benefits, but species B is harmed. In this case, the parasite lives and feeds on its host, thus decreasing the host's ability to survive, but not killing it. Parasites likely make up half of all living species and parasitic interaction is the way that these species survive.http://www.britannica.com/EBchecked/topic/129392/community-ecology/70602/Interspecific-interactions-and-the-organization-of-communities#

Examples of common parasites include lice, bed bugs and fleas, which attach to species such as humans and other mammals to feed on their blood. Though not fatal, these parasites easily spread from one host to another and can cause itching and other discomforts.http://www.nlm.nih.gov/medlineplus/headlice.html