Freshwater Sponges: A Most Ancient and Wonderful River Friend
The leaves are falling again, and soon enough we’ll view without obstruction the muscular bodies of our hills and valleys.
I think of geology when I see our biome bared: the thermochemical transformations that over eons have given us our sandy happy valleys and smooth rounded granite ridges.
400 million years ago our mountains were the first and tallest in what is now North America; 200 million years ago the subterranean lava leaks that are now Mt Holyoke and Mt Tom were spluttering; 90 million years ago the Atlantic Ocean formed, splitting North America off from what is now Europe and Africa; and very recently, only 13,000 years ago, the Laurentian Ice Sheet crushed the mountains into boulders and pebbles, then melted and those waterfalls and rivers spewed the grits out into the ocean, where they formed Long Island and Cape Cod. Yes—the sands of P-town come from here, where we live!
The shared identity of our lovely highlands and the beaches we visit in summer is something I’m constantly fascinated by, mainly because where so many see difference I perceive unity. This holistic perspective is a product of my passionate embrace of ecology, a science that unites biology with geology and climatology. It is also drawn from my love for Transcendentalism, the wonderful tree-hugging religion invented in Massachusetts by, amongst others, Ralph Waldo Emerson, who wrote:
“There is a property in the horizon which no [person] has but [s/he] whose eye can integrate all the parts, that is, the poet.”
The most obvious reason I can’t separate our hills and valleys from the beaches is because whenever I riverwalk I see lobsters, whoops, I mean crayfish and clams, whoops, I mean fresh water mussels. Once upon a time, the ancestors of these crayfish and mussels lived in salt water. Given that these ancestors were alive over 350 (for crayfish) and 250 (for mussels) -million years ago, it is safe to say that the crayfish and mussels we find in our rivers survived the geological and climatic changes that gave rise to and killed off the giant dinosaurs, whose footprints we find in Holyoke and Montague. How did they do it? I don’t know—but I love to think about it!
Of all the river beings who remind us of the unity of our highlands and our beaches, the most startling is the lime-green freshwater sponge that you sometimes encounter downstream of swamps and beaver dams. Its ancestors lived in salt water over 500 million years ago—100 million years before the mountains that form the basis of hills and valleys rose to Himalayan heights. I am always blown away when we meet each other around here, not only because they are most venerable of the multi-celled river beings, but also because—if you click on that last link—you’ll find that they are not documented as living around here yet!
According to the DEP, “Only two populations of Smooth-Branched Sponge have been found in Massachusetts in ponds in Dukes and Worcester counties” and the “true range of this species is unknown.”
It is only by being there that we can sense what is being—so, please, get out and get walking; visit your local river and get to know it. Once you do, you’ll love it, and when that happens your world will be bigger, wilder and more beautiful—I promise!
ABOUT THE AUTHOR
Kurt Heidinger, Ph.D. is the Executive Director of Biocitizen, non-profit school of field environmental philosophy, based in the Western MA Hilltown of Westhampton, MA where he lives with his family. Biocitizen gives participants an opportunity to “think outside” and cultivate a joyous and empowering biocultural awareness of where we live and who we are. Check out Kurt’s monthly column, The Ripple, here on Hilltown Families on the 4th Monday of every month to hear his stories about rivers in our region. Make the world of rivers bigger than the world of pavement inside of you!
[Photo credit: (cc)]