On Weds evening, Ian arrived in Southern California (Los Angeles) to visit the Echinoderms Collection at the Natural History Museum of Los Angeles County. Ian had previously worked with the Collections Manager, Cathy Groves, and Curator of Echinoderms, Gordon Handler, on historical sea stars in 2014 as part of our wider study into SSaDV in asteroids on the Pacific Coast; this aspect of the project revealed that SSaDV had been present on the west coast of North America for >72 years based on amplification of two genes on SSaDV’s genome. One of the goals of our new project is to examine how genomes have varied across their entire length between then and now, and also geographically. To this end, Ian sampled an additional 45 asteroids, from the 1940s and late 1990s from southern California. The process of sampling these animals is quite complicated, as first the specimens need to be located amongst the collection, then they need to be documented, tube feet excised, then the specimens labeled to reflect that they had been sampled. The reason for this is that, sometime in the future, other researchers may come along and find tube feet missing – which may be interpreted as an actual injury or perhaps a deformity!
Three specimens sampled: Left are Pisaster ochraceus, middle is Pisaster gianteus and right two photos are Pycnopodia helianthoides.
A key part of this sampling were the large number of juveniles. In the current epidemic, SSaDV has very much higher load and prevalence in really, really small juveniles, so it will be useful to know whether these are also harboring SSaDV in such high loads.
Two photos of juvenile Pisaster ochraceus
Next, Ian gave a talk on the wasting disease work, which details efforts made in 2013 – 2014, and our current work. All in all it was a productive day, and samples are now safely back in LA.
One of the most amazing museums in the US – the Echinoderm collections at the NHM (and others) represent enormously valuable resources for scientists who wish to look through time at the biology of invertebrates.
Next up Ian will travel back to Ithaca to analyze these samples with Elliot, as well as work on some new material which has arrived in the lab.