Tuesday, November 20, 2012

New Babies – Peanut Worms!

We have some new babies in the lab this week.

Newly hatched.   And a new kind of invertebrate for us to work with: Sipunculan worms.

These little guys were spawned in a dish last week and we are keeping our eyes on them to see how they grow.   What kind of development they have.  How long before they settle.  At this early stage it’s a bit hard to imagine how they are going to grow.

Sipunculid worms are often relegated to the “The Lesser Phyla” in invertebrate text books.    It’s true they are not well-known or well-studied.  But they hold great potential to answer some very interesting questions about developmental processes and how the body plans of different invertebrate larvae evolve.   Dr. Michael Boyle will be joining the CollinLab early in 2012 so we will all be learning more about these funny looking little worms.

Friday, November 16, 2012

Hunting Peanut Worms in the Caribbean

Last month some of the Collin Lab members set out to the field at first light.  They were headed all the way across the country (a full hour’s drive!) to Galeta Marine Laboratory on the Caribbean coast of Panama.  This lab hosts research but is primarily used for outreach and education for kids in the city of Colon.  

Panamanian students learning about their 
environment from STRI Nature Guides.

With seagrass lagoons, mangroves and coral 
reef patches, Galeta is one of the most 
well-studied Caribbean sites in Panama.
The goal of the trip was to hunt for peanut worms.  They are the center of a biological controversy.  Are they regular segmented annelid worms that have lost their segments.  Or is the un-segmented body with a strange inverting proboscis unique and evolved independent of other worms?  We join Tupper Postdoctoral fellow Michael Boyle in a search of these peanut worms.
Intern Allan Carrillo searches for substrate

The worms are often found inside rock crevices and coral rubble or mud flats.  That’s why, we needed to collect rocks and coral rubble from shallow water (0.3-2 m).

We didn’t just see worms.  If course, we saw slugs and snails too.   The reef-flat is full of interesting invertebrates and seaweeds. 

But, most important, we found them!!! A bunch of specimens of Phascolosoma perlucens and Aspidosiphon sp. that with luck, will spawn.   If they do, Michael might use them as a model for his studies of evolution of development.

Michael carefully cracks open dead
coral heads to look for the worms.

And....after all that hard work... here he is!  

Phascolosoma perlucens!

Post prepared by:  Allan Carrillo