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Here are some images and videos of our work:

The ciliate Strombidium oculatum feeding on Ulva sp. zoospores
This short clip shows the ciliate Strombidium oculatum grazing on thalli of the green macroalga Ulva sp (formerly Enteromorpha). The whitish area of the alga, where the ciliates are congregated, is reproductive tissue. That is where the alga releases swarmer cells that function in reproduction and dispersal. These cells are approximately 10 micrometers in size, just right for ingestion by the ciliate. (see MCMANUS, G. B., H. ZHANG, and S. LIN. 2004. Marine planktonic ciliates that prey on macroalgae and enslave their chloroplasts. Limnol. Oceanogr. 49: 308-313) [pdf link].
Strombidium stylifer undergoing cell division (l) and the tintinnid Metacylis angulata (r) "hanging out"
Stylifer dividing
Tiarina fusus , live cells. The ciliate's calcium carbonate internal skeleton can be seen.
Favella sp. under DIC, showing a cyst held inside the lorica (left) and Strombidium oculatum (right) with its orange eyespot
Strombidium stylifer under DIC (left) and fluorescence (right) illumination. Right image shows the macronucleus stained with the fluorochrome DAPI
Fabrea salina cyst
Cyst resting stage of the ciliate Fabrea salina. Rachel isolated this ciliate from the Salton Sea. It can survive at salinities above 100! We are trying to find factors that cause it to encyst and are hoping to do some single-cell transcriptomics to find out what genes may be expressed while the ciliate is encysted.
Light microscope pictures of the S. stylifer/oculatum coplex


These images show the morphological variation in ciliates collected from a single population in a tide pool in Dublin Bay, Ireland in 2002. All of the ciliates are grass-green and contain an orange-red eyespot. We initally identified them as Strombidium oculatum, a species that has been well-studied by other researchers (see references below). However, DNA sequencing has shown that there are at least a dozen different forms that differ by as much as 16%, a level that is much greater than what is found within species in other organisms. Now we are trying to solve a puzzle: How do all of these different forms co-exist in a single tidepool, eating the same food (green algae), without one of them outcompeting the others to extinction, as ecological theory would suggest? Somehow, they partition the habitat in many ways. At this point, we have only been able to cultivate one of the "species", which we are calling Strombidium stylifer. When we can get more of the forms into cultivation, we hope we can do experiments to help us understand how they are ecologically different.


FAURE-FREMIET, E. 1948. Le rythme de maree du S. oculatum Gruber. Bull. Biol. France-Belgique 82: 3-23.

JONSSON, P. R. 1994. Tidal Rhythm of Cyst Formation in the Rock Pool Ciliate Strombidium-Oculatum Gruber (Ciliophora, Oligotrichida) - a Description of the Functional Biology and an Analysis of the Tidal Synchronization of Encystment. Journal of Experimental Marine Biology and Ecology 175: 77-103.
KATZ, L. A. and others 2005. Reframing the 'Everything is everywhere' debate: evidence for high gene flow and diversity in ciliate morphospecies. Aquatic Microbial Ecology 41: 55-65.
MCMANUS, G. B., H. ZHANG, and S. LIN. 2004. Marine planktonic ciliates that prey on macroalgae and enslave their chloroplasts. Limnol. Oceanogr. 49: 308-313.
MONTAGNES, D. J. S., C. LOWE, A. POULTON, and P. R. JONSSON. 2002. Redescription of Strombidium oculatum Gruber 1884 (Ciliophora, Oligotrichia). Journal of Eukaryotic Microbiology 49: 329-337.
MONTAGNES, D. J. S., D. WILSON, S. J. BROOKS, C. LOWE, and M. CAMPEY. 2002. Cyclical behaviour of the tide-pool ciliate Strombidium oculatum. Aquatic Microbial Ecology 28: 55-68.