To the Aquarium! by Darsi Fouillade

I love fieldtrips like these, as much as I loved reading Magic School Bus stories to my kids when they were younger.  It is one thing to learn about science in a classroom, but it is a whole different experience to take that learning and apply it in a more natural setting.  Instead of one Ms. Frizzle, we had our fearless teacher Gwen Schlichta and countless volunteers ready to answer our Metazoan questions.  I chose the aquarium fieldtrip because it had been awhile since I had been there, many of my classmates would be there too and as such, a great chance to use our newfound Phyla knowledge as we explored the different types of aquatic organisms.   

And there were so many different examples from the major sections of the animal kingdoms!

In just this one place, we could view Porifera, Cnidaria, Nematodes, Arthropods, Mollusca, Echinodermata, and many, many examples of Chordates.  After being assessed on phylogenies already twice, this third exposure was gratifying and real.   

Scallop living on the "Edge"

Take that of the Scallop.  This bivalve of the Mollusca phyla feeds off phytoplankton from the natural stream of water the aquarium pumps from outside Puget Sound water.  The scallops filter through this material via their gills.  They have a hard shell that they can open and close depending on how protected they need to be from predators and wave action.   And as fellow student pointed out, "See how they have so many eyes!"

Another example is the Sea Star, which is pentaradial and from the Echinodermata family.  They grip tightly to rocks and each other to prevent being moved by wave action.  During their Wednesday feeding, many oysters were dropped near them.  They were in no rush to feed, but when they are ready, they sense the food and then move over it.  The volunteer explained how they use their feet to open the shell and then their stomach comes out of their mouth to ingest contents and then returns back into the sea star.  Although they are soft to the touch, they have tough enough skin flexible hydrostatic skeleton to avoid abrasion from the moving waves and contents.  For further protection, they also congregating together, interweaving their arms with the other nearby sea stars.

The third example was the Calcareous Tube worm, which is part of the Annelid family.  These worms make a calcified (calcite and argonite) slightly curved home attached directly to rocks.  Their body stays protected in this tube and their top end can peak out of this home wit

Tube worm

h the feather duster type of head to filter feed any nutrients (phytoplankton and detritus) that are moving by. They then retract their head when needed.  They have an excellent way of avoiding desiccation and abrasion to wave action, they just make their cement type hard home and stay there for the good.  Watch out for those slow-moving sea stars though!  By the way, there is an example of this type of worm on page 878 of our book.

The fourth example Is from the Arthropod family, and that is the Hermit Crab.  These cute guys acquire their shells from the recycling market.  Their shell not only shelters them from wave action, temperature extremes, but also is a reservoir for water when the tide is in.  They were eager to eat some chopped fleshy sample during feeding time, although they will also eat phytoplankton.

Giant Tropical Clam

My favorite organism represents adaptive radiation at its best.  The Mollusca phyla is a great example of adaptive radiation because even within this phyla, there is such great diversity: from a garden snail, to a clam to an octopus.  This organism appeared to be a clam which had opened into this beautiful phosphorescent mantle.  It was enormous, tropical looking and amazing!  Apparently these giant clams can get as a large as a meter wide.  My question is what is the adaptive advantage here, to be big and glowingly amazing?  Could it be that its rapid growth rate is due to its ability to cultivate algae in its body tissue like the Tridacna maxima species can?  Clams in general are filter feeders, so this one must have it down to an art.  Literally.  So why the beautiful mantle surface?  In a Ms. Frizzle voice, "Let's Take a Closer Look!" It seems it is the symbiotic relationship with zooxanthellae that live on this mantle surface.  Part of the color comes from the clam, the other part comes from this hosted single celled algae.  Outstanding!

We were able to hit many of the feeding times that day, from the already mentioned intertidal zone organisms, to the large aquarium and the seals.  There was some time spent walking through the bird and salmon exhibits too.  These shorebirds use the beaches, cliffs and rocky shores by way of feeding and nesting.  The long-billed curlew uses its long beak to search for food in the rocky crevices in the coastal tidal mudflats.  When they nest they look for dirt mounds and rocks for camouflaging.  Shoreline modification and coastal erosion could have an impact on these birds because they will have less areas to mate and less rocks and flats to camouflage their nests.

Sturgeon - he has been here for awhile.

The Pacific salmon also face threats from the effects of urbanization and farming too.  One hazard is the increase in river temperature.  If there is not enough trees and coverage upstream, this will increase the river temperatures.  Salmon will not make their run upriver if the temperatures are too warm and instead stay in the oceans longer.  They do not eat while they are on their trip upriver but do need enough water running in the streams (enough snow melt) so they can return to the stream they were born in (hopefully) and lay eggs for the next generation.  Finally, another threat to them is competition from the hatchery fish. 

Jelly Fish

This fieldtrip really connected class concepts to actual organisms and helped me really appreciate how much diversity there is in the animal kingdom, and how this diversity came about.  Overall, this field trip refreshed my commitment to the efforts of acquiring knowledge of a stem subject like biology.  It takes some to grasp how things are connected, but it is so worth it to be able to go into a place like the aquarium and to come up with possible answers of how the structure, function and location of these organisms characteristics allows them to fulfill the niches that they do.   It seems it is magical, just like being on an actual magic bus ride.  And signing off with one last Ms. Frizzle quote, that resembles the failure bow of learning new material:

"Take Chances, Get Messy, Make Mistakes"