"Chili Pepper" Siphonophore
The team has seen several siphonophores during our exploration of the Gulf of Mexico in 2014 and 2015. Siphonophores are not one organism, but rather colonies of multiple symbiotic organisms co-existing in one structure.
On this leg of the expedition, we will return to cold methane seeps and brine pools investigated during the 2014 season to continue an examination of the symbiosis between the mussels that live at the seeps and the bacterial symbionts that they host. Previous work has shown that different species of Bathymodiolus mussels have different combinations of symbionts that allow them to survive under varied conditions at the seeps. The symbionts utilize hydrogen sulfide or methane. Sulfide-oxidizing symbionts use the energy from sulfide to grow using CO2 as their sole carbon source.