By Emma McGeary, with scientific information provided by Dr. Tim Pearce, Curator of Collections & Head in the Section of Mollusks
This activity has a few steps, but it’s a great way to explore something really unique— the fluorescing slime of various land snails!
Dr. Pearce says that malacologists (people who specialize in the study of mollusks, like snails and slugs) aren’t sure yet as to why some snails have fluorescing slime, they have a few theories. For example, the slime of Mountain Tigersnails (Anguispira jessica), does not typically fluoresce. However, the slime produced as a defense mechanism by Mountain Tigersnails, which is a yellow-orange color, does fluoresce. With this information, Dan Dourson, a Biologist, suggested that the fluorescing slime could possibly be a way for the snails to protect themselves. If a predator saw the bright slime under the light of the moon, it could make them no longer want to prey upon the snail. Flamed Tigersnails (Anguispira alternata) have been found to have fluorescing slime as well.
Dr. Pearce also mentioned that this fluorescence may also be something not meant to be functional, but rather a “side effect” of evolution that serves little purpose. Because scientists are still searching for an answer, they have to look critically at all different kinds of possibilities.
Questions to Consider
Could the slime be a functional way to keep the snails safe? If so, when might they encounter UV light in the wild? Is the fluorescing quality of this snail slime a byproduct, or result, of evolution? If that’s the case, what evolved traits could have caused it? If you think that the fluorescent slime has nothing to do with defense or a random act of evolution, then what else could be behind the mystery? Using your knowledge of the natural world, see if you can think of explanations as you work on your own snail slime sensory bag.
Make-Your-Own Snail Sensory Bag
What You’ll Need
- 1 Bottle (6oz) of Elmer’s Clear Glue (this type of glue works best)
- 1.5 Teaspoons Baking Soda
- 1.5 Teaspoons Contact Lens Solution (I’m using Bio True)
- Spoon (or another mixing utensil)
- Sealable plastic bag
- Food coloring or paint (optional)
- Permanent Marketing (optional)
- Beads (optional)
- UV light (optional)
- Empty your bottle of clear glue into your bowl. If you are adding food coloring or paint, this is the best time to add it!
- Add your baking soda to the glue and stir.
- Add your contact solution and stir.
- You may need to knead this slime with your hands to have it become less sticky.
- Add your slime to your bag and close it. If you would like to turn this sensory bag into a sensory activity, draw a snail onto the front of the bag. Make sure the shell is large!
- Add your beads, if you would like. You can use your fingers to move the bead in the bag around. See if you can color in the snail shell by moving the beads into it!
I made sure to use a neon paint for this bag so that it would glow under my UV light! The beads I added were glow-in-the-dark beads, which also meant they glowed under the UV light.
The mystery of fluorescing snail slime is only one of the many things that have caught Dr. Pearce’s interest. He has also been researching their decline and disappearance throughout Northeast North America, which may be attributed to past decades of acid rain and determining the amount of Anguispira species there are on the continent as well. Dr. Pearce says that the attempt to find that number is a large collaborative effort that involves looking at the snail’s DNA and taking trips out to collect specimens. While out in the field, Dr. Pearce has also attached spools of thread to snail shells to track their movement in the wild!
Sometimes, finding an answer to a scientific question can take a long time and many discussions with others. Now that you’ve learned a little more about how snail slime works and the unique type of slime that certain snails have, think about how you could put your own theories to the test, and what else you could learn about snails by observing them in their natural environment!
Of course, no discussion of snails could be complete without one of Dr. Pearce’s famous snail jokes:
What do tiger snails have that NO OTHER animal has?
Baby tiger snails!
Emma McGeary is a Gallery Experience Presenter in CMNH’s Life Long Learning Department.