Welcome to BrainStuff, a production of I Heart Radio.

Hey Brain Stuff, Lauren Bogobam here.

In nature, there's a certain ethos of all scratch your back if you scratch mine.

Living things never exist in isolation,

and organisms of different species occasionally need to cooperate

in order to get stuff done.

And sometimes, one organism takes the benefit from another

while that other one blithely lives its life,

unharmed but blissfully unaware of the service it's performing.

Colologists call this form of half passive cooperation, commensilism, and it's different

from some other ways that members of an ecosystem can interact.

For instance, commensilism isn't the same thing as

parasiteism, where one partner, the parasite, lives on or in the body of a host and

only one partner actually benefits while the other is harmed.

It's also not exactly the same as mutualism,

where both partners benefit from the partnership.

But think about the relationship between bees and flowers.

The bee gets food while the flower accomplishes its reproductive goals.

Commensilism involves one organism just going about its business,

while one or more others called commensals just sort of hang out and benefit from that one guy's hard work.

We spoke with Amanda Hips, Director of Communications and Development at Wild Landscapes International.

She said, one of my favorite commensal relationships is the one of

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