jellyfish are still alive!

As far as I know, our second batch of upside down jellyfish is still alive! This is the 1 month marker. We've also managed to take some data on the flow fields around the bell as they contract using piv (particle image velocimetry). The big problem is controlling the algae in the tank, but we've ordered a protein skimmer (to remove the debris the algae eat). We will need to redesign the tank though with a separate compartment for all of this filtering. 

The brine shrimp hatchery has arrived and I'm looking for the best place to set up. The grow light for the smaller set up seems to be working, but I don't have anything for the hatchery right now. We have no temperature control in the basement, and I think it's a little bit too cold for the shrimp. I have learned through trial and error that temperature is easily as important as light. So I'll need to find a warmer spot or find some way of heating the water.

The tunicates died back about two weeks ago. We thought we had perhaps poisoned them with the algae concentrate we had been using, but now it looks like they are growing back. Perhaps a natural life cycle? We'll see what happens this time. We discovered at least two other species of tunicate in the tank that apparently hitched in on the live rock. No idea on the identifications, but we'll see what we can find. It seems like every time I look into the tunicate tank, there is something new popping up. Very exciting!

After a false start with the first batch of Cassiopeia, we finally have a set of three gulf specimens relatively settled and happy. We're dealing with a golden algae bloom, probably hitchhikers from the jelly transport bags.

The algae cultures are snug in their new foil-lined lair. There are four cultures of distinct algae types and all seem to be growing nicely. Pictures and species names to follow soon!

Starting to put the tanks together

We just got in a 20 gallon and a 29 gallon tank and have started to set up the filtering systems for both. The first animals I'm going to order are some sea squirts, likely Clavelina picta. I've got to figure out how to culture algae to feed them before shipping them to North Carolina (it shouldn't be too hard, I hope). Once they arrive I'll definitely post some pictures!

The next step will be to order some of the upside down jellyfish like the mangrove jellyfish (see picture). Supposedly, they can be kept in normal tanks, but they don't really swim. They pulse their bell to generate currents for feeding. Since they can't see, we will be able to use particle image velocimetry (piv) to quantify the flow fields around the bell without worry of harming them with the laser.

Setting up salt water tanks

Now that we have a few rooms in the basement of Phillips Hall (and I have a little bit of time), we are going to try to set up a couple of salt water tanks. I'd like to try to keep the sea squirt Ciona savigny in the lab and use it to measure fluid flow induced by cilia and contractions through the siphon and body. We're going to try to do this using particle image velocimetry (piv). Hopefully, the flash of the laser will not startle them. It may also be a challenge to keep them alive. They need moving water and a constant supply of food (it is harder than it sounds). If all works out, eventually I'd like to work up to taking measurements of flow rates in their heart and blood vessels.

The next step is going to be to keep some jellyfish alive in the lab. This should be more exciting for students and visitors since they actually swim! The problem is that these animals do not do well with walls. They have a tendency to slam into them and get stuck. Supposedly, cylindrical tanks with a jet that flows around the wall can keep them in the center of the tank and happy. If we can get this to work, we should be able to get spatially and temporally resolved flow fields as they swim. John Dabiri at Caltech has gotten excellent data from these animals already. Hopefully we can reproduce some of the work as an outreach tool. 

 

Welcome to the Math Physiology Group's Blog!

Hopefully this will be a good way to keep group members and friends up to date on what is going on in our new math physiology lab at UNC. I'll post some information soon about our attempts to bring in sea squirts and keep them alive in Phillips Hall Basement!