WEBVTT - What Is Commensalism?

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<v Speaker 1>Welcome to brain Stuff, a production of I Heart Radio,

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<v Speaker 1>Hey brain Stuff, Lauren Vogelbaum. Here in nature, there's a

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<v Speaker 1>certain ethos of all scratch ere back if you scratch mine.

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<v Speaker 1>Living things never exist in isolation, and organisms of different

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<v Speaker 1>species occasionally need to cooperate in order to get stuff done,

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<v Speaker 1>And sometimes one organism takes the benefit from another while

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<v Speaker 1>that other one blithely lives its life unharmed but blissfully

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<v Speaker 1>unaware of the service it's performing. Collegists call this form

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<v Speaker 1>of half passive cooperation commence all is um, and it's

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<v Speaker 1>different from some other ways that members of an ecosystem

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<v Speaker 1>can interact. For instance, commence allism isn't the same thing

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<v Speaker 1>as parasiteis m, where one partner the parasite lives on

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<v Speaker 1>or in the body of a host and only one

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<v Speaker 1>partner actually benefits while the other is harmed. It's also

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<v Speaker 1>not exactly the same as mutualism, where both partners benefit

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<v Speaker 1>from the partnership. But think about the relationship between bees

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<v Speaker 1>and flowers. Of the bee gets food while the flower

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<v Speaker 1>accomplishes its reproductive goals. Commence ali is um involves one

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<v Speaker 1>organism just going about its business while one or more

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<v Speaker 1>others called commence als just sort of hang out and

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<v Speaker 1>benefit from that one guy's hard work. We spoke with

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<v Speaker 1>Amanda Hips, director of Communications and Development at wild Landscapes International.

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<v Speaker 1>She said, one of my favorite commensal relationships is the

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<v Speaker 1>one of Eastern screech owls and blind snakes. The owls

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<v Speaker 1>bring live blind snakes to their chicks, while some of

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<v Speaker 1>the snakes are eaten. The lucky ones burrow into the

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<v Speaker 1>nest and eat insect larva that they find there, lava

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<v Speaker 1>that would likely parasities the chicks. A study by scientists

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<v Speaker 1>from Baylor University found the chicks who grew up in

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<v Speaker 1>nests with blind snakes grew faster and experienced lower mortality

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<v Speaker 1>rates compared to nests without blind snakes. We can observe

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<v Speaker 1>three main types of commence all is um in Quillinism

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<v Speaker 1>is when one species lives on or inside of another species,

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<v Speaker 1>the way that our gut bacteria live inside us or

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<v Speaker 1>within a nest, burrow or dwelling created by another species.

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<v Speaker 1>For instance, gopher tortoises, which are native to the southeastern

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<v Speaker 1>United States, did long burrows for shelter, some of them

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<v Speaker 1>reaching forty feet or twelve meters in length. Hundreds of

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<v Speaker 1>other animals have been recorded using these burrows. Some of

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<v Speaker 1>them have even evolved to require the burrows of the

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<v Speaker 1>gopher tortoise in order to survive. Most of the commence

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<v Speaker 1>als are insects, but these burrows are also important to

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<v Speaker 1>a variety of species of snakes, frogs, and small mammals.

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<v Speaker 1>Hips said, there are fourteen recognized insects that are fully

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<v Speaker 1>reliant on gopher tortoises. One of these species is a

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<v Speaker 1>moth that feeds exclusively on the keratin of the shells

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<v Speaker 1>of dead gopher tortoises. Some of the remaining insects feed

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<v Speaker 1>on gopher tortoise doung Others feed on pest flies or

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<v Speaker 1>other organic matter inside the tortoise burrows. I like to

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<v Speaker 1>think of them as a housekeeping service to the gopher tortoise.

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<v Speaker 1>Although the impacts they have on gopher tortoises is not

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<v Speaker 1>yet understood, they likely lower parasite loads for tortoises and

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<v Speaker 1>the other vertebrates that also take advantage of the burrows.

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<v Speaker 1>Another kind of commence all is um is called metabiosis,

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<v Speaker 1>wherein one organism unintentionally forms a habitat for another while

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<v Speaker 1>just going about its normal business. For example, maggots need

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<v Speaker 1>to live somewhere, and it's often on or in the

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<v Speaker 1>carcass of a dead animal that, to be fair, wasn't

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<v Speaker 1>using that carcass anymore. Similarly, the gilo woodpecker makes its

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<v Speaker 1>nest in the cavity of the saara cactus, and hermit

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<v Speaker 1>crabs protect themselves and the discarded shells of snails and

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<v Speaker 1>other gastropods that have outground them. Meanwhile, for a c

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<v Speaker 1>is a type of commence ali is um when one

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<v Speaker 1>animal attaches to another in order to catch a ride

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<v Speaker 1>from one place to another. For instance, a nematode or

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<v Speaker 1>might can't really get very far on its own unless

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<v Speaker 1>it climbs on board a bee or a fly. The

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<v Speaker 1>might or nematode gets a huge benefit from the exchange,

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<v Speaker 1>whereas the bee or fly doesn't really benefit or suffer

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<v Speaker 1>from the interaction. While commence all um is a huge

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<v Speaker 1>benefit for some of the organisms in the deal, it

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<v Speaker 1>can be really tricky for an ecosystem under stress. Hips said, Ultimately,

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<v Speaker 1>I think having more commence ali is um in an

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<v Speaker 1>ecosystem could make an ecosystem more vulnerable if you lose

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<v Speaker 1>one species you could lose another If gopher tortoises went extinct,

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<v Speaker 1>we will undoubtedly lose other species along with it. Today's

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<v Speaker 1>episode was written by Jescelin Shields and produced by Tyler Klain.

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<v Speaker 1>For more on this and lots of other topics, visit

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