Insightful and spiritual thoughts on everyday life related to the natural world, accompanied by photographs and artwork by the author.
Friday, April 16, 2010
Millions of Hiding Places
A brownish cloud had suddenly appeared in one of the small aquaria and was squirming with life. Did I know what it was? Calling during his lunch break, the outreach instructor could not wait to tell me what he’d discovered while carrying our marine life lessons into a local elementary school. From his description I wasn’t sure, but could not wait to find out. Later that day, when he returned to the Marine Science Center, we managed to catch a few of the tiny creatures and view them through a microscope. One look told me - barnacle babies.
These amazing creatures begin life as microscopic larvae that swim about with feathery legs. In a short period of time their bodies change, resembling small shrimp with transparent umbrellas attached to their backs. Within the immense ocean, attracted by specific chemicals, they are able to locate others of their same species and search for a place to “settle”. Crawling among the shells of other adult barnacles, they check out each nook and cranny until they find a spot they deem satisfactory. Producing a natural glue - among the toughest substances known - they attach themselves head-down; extracting calcium from the sea water, they form six hard plates around their bodies. For added protection, they make a 4-part door at the top of their shelter, which they can open and close at will. Their bodies have undergone yet another change so that they no longer resemble the original larval form, nor the shrimp-like creatures they once were. They are quite unique - upside down and permanently attached to their shell.
Each barnacle spends the rest of its days, trapped if you will, within the confines of a small, sturdy fortress it has constructed for itself. As it grows, it must shed its skin and enlarge its shell plates. In order to feed, it must warily open its door and comb the water with its feathery legs, pulling bits of plankton inside to where its mouth is located. In doing so, does the barnacle feast on the young of its own kind? I suspect it does. Life in the sea is a dogfish-eat-dogfish world, so billions of young are produced to ensure survival of each species.
For the barnacle, securely attached to one place for life, finding a mate could be a problem. It can’t roam around to find one but it can, and does, settle close to one. Each animal is both male and female, but they cannot produce offspring alone. The fertilized eggs of each are brooded within the shell of the adult until they develop into the first larval stage. Then a cloud of up to 13,000 larvae is released, with each tiny creature on its own in the waters of the deep. Most are eaten, or otherwise perish.
Some do survive, however, to built their unique hiding places and continue to live out of sight. Their rugged little shelters protect them from most predators, careless feet, violent waves, winter cold, summer heat and dehydration during twice-daily low tides. And as each tide flows in, flooding them anew with fresh, cold water, they open their doors to the feast that surrounds them.
As days lengthen and we stroll the docks, beaches and shorelines, may we pause to contemplate the common barnacles; may we marvel at the lives lived within those plain, rugged shells.