Because bee orchids can also self-fertilize, and thus survive without their mutualistic partner, they’re an example of facultative mutualism. The blue streak cleaner wrasse, or cleaner fish ...

In some cases, the species are entirely dependent on each other (obligate mutualism) and in others, they derive benefits from their relationship but could survive without each other (facultative ...

known as obligate mutualism; and species that have a friends-with-benefits approach, known as facultative mutualism. This latter type gets something out of the relationship, but they'd survive ...

Or, it can be a looser association called facultative mutualism (some wrasse will pick parasites off larger fish, offering cleaning services in exchange for a small meal). It also doesn’t have ...

The signs of the intrinsic growth rates distinguish between facultative mutualism if the α i are positive and obligatory mutualism if they are negative. Structural stability is often defined as ...

They dubbed the relationship "facultative mutualism." When researchers flooded the environment with nutrients, the two strains became competitors, with one strain thriving and the other losing out.

With just a small amount of extra added nutrients, the strains established an "obligate mutualism," in which they were obliged to co-exist in order to survive. With more nutrients, a "facultative ...