The relationship between Gracilaria & Diopatra
photo: http://www.dnr.sc.gov
A Relationships between biotic components of a given ecosystem can take many forms. When we are speaking of more long-term, close interactions between different species, the relationship can be described as symbiotic. So close in fact, many formal definitions of symbiosis include the phrase "living together".
There are several ways to categorize symbiosis. The relationship can be beneficial to both organisms involved (mutualism), good for one and bad for the other (parasitism), or good for one with nothing either beneficial or harmful to the other (commensalism).
The Sotka lab is interested in how the invasive algae, Gracilaria vermiculophylla, interacts with biotic components of the mud flats it is found on. One of those interactions is with the plumed worm, Diopatra cuprea.
The plumed worm is a common sight on Southeastern shorelines. This omnivorous worm glues sediment and plant material together to build a hooded tube that protrudes from its soft surroundings. Check out a neat video of it building its home here. As Gracilaria has invaded our coast, Diopatra has made use of it by adding it to its tubes, in return anchoring the plant to the mud flat. Can you hypothesize what kind of interaction is between the algae and the worm?
There are several ways to categorize symbiosis. The relationship can be beneficial to both organisms involved (mutualism), good for one and bad for the other (parasitism), or good for one with nothing either beneficial or harmful to the other (commensalism).
The Sotka lab is interested in how the invasive algae, Gracilaria vermiculophylla, interacts with biotic components of the mud flats it is found on. One of those interactions is with the plumed worm, Diopatra cuprea.
The plumed worm is a common sight on Southeastern shorelines. This omnivorous worm glues sediment and plant material together to build a hooded tube that protrudes from its soft surroundings. Check out a neat video of it building its home here. As Gracilaria has invaded our coast, Diopatra has made use of it by adding it to its tubes, in return anchoring the plant to the mud flat. Can you hypothesize what kind of interaction is between the algae and the worm?
A noval Mutualism
Nicole's research showed that Diopatra decorating its tubes with Gracilaria can be beneficial to the algae. This is because Gracilaria vermiculophylla can anchor to the mudflut at a tidal height favorable for growth. In return, Gracilaria indirectly provides Diopatra with a food source. Results from lab experiments suggested that Diopatra benefits more from consuming the invertebrates that live on Gracilaria than from consuming Gracilaria directly.
Nicole also found that given the right conditions in the field, the growth of Diopatra is correlated with the density (how much stuff is in a given space) of Gracilaria. There was also a positive relationship between the density of Gracilaria and the invertebrates present on the seaweed.
Nicole also found that given the right conditions in the field, the growth of Diopatra is correlated with the density (how much stuff is in a given space) of Gracilaria. There was also a positive relationship between the density of Gracilaria and the invertebrates present on the seaweed.