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Spotted Salamander Pond
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As you will read, when I went online to learn more about the particular species I had come upon, even more marvels began to emerge. Thanks to a scientific discovery published only one year earlier, I would now have the opportunity to journey back even farther — long before vertebrates evolved, long before eukaryotes evolved. I would experience, in microcosm, the primordial time when the bacterial realm was assembling the chemical cycles essential for life. Spotted Salamander egg masses enabled me to journey back in my imagination to that Archaean time because they so visibly display, what I like to call, Gaian symbiosis in miniature.
I'll begin this report with an entry I made in my journal. There you will see my excitement begin to build for, what would turn into, an opportunity to relive two profound transitions in our evolutionary heritage. As background, know that my husband and I were on a writing retreat in a cabin alongside the very rural home of our friend Tobey Miller in the northeastern corner of Alabama, from February 23 to April 24, 2011.
MARCH 1 journal entry:
Later on March 1: "This afternoon I discovered 5 blobs of eggs in Salamander Pond — new because three were attached to a large stick I tossed in just a day or two earlier."
 
ABOVE RIGHT: March 2, I temporarily pulled out to examine a glob of salamander eggs that had probably been laid the night before during the rain. The glob is attached to a leaf that was resting on the bottom, so it may have been laid a day or so before I tossed some hefty sticks into the pond in hopes of improving habitat for salamanders. (I knew big sticks are valued because, while living in the Pacific Northwest two decades earlier, I had come upon an ephemeral forest pond and noticed masses of newt eggs attached to floating or partially buried sticks.)
 
 
ABOVE RIGHT: March 17 - This was the first day I detected the transformation. Notice how within the jelly mass, each embryo has its own protected sphere to develop within. Now notice how those spheres have turned bright green! Just the spheres are turning green — not the enveloping protective jelly. What's going on?
  Scientists have stumbled across the first example of a photosynthetic organism living inside a vertebrate's cells. The discovery is a surprise because the adaptive immune systems of vertebrates generally destroy foreign biological material. In this case, however, a symbiotic alga seems to be surviving unchallenged — and might be giving its host a solar-powered metabolic boost.
LYNN MARGULIS is best known for her success in advocating that some of the major transitions in evolution (notably, the birth of the eukaryotic cell) occurred through an intimate form of symbiosis called symbiogenesis. The scientific community now agrees that several of the components within eukaryotic cells were absorbed directly as bacteria from the surrounding environment, from which a mutual dependency emerged. Chlorophyl plastids within the cells of all photosynthesizing plants had spent hundreds of million of years entirely as free-living, sun-loving bacteria before the merger occurred. As well, the oxygen-consuming powerhouses in all plant and animal cells (the mitochondria) began as free-living bacteria, too. So why do I call the alga-rich embryo sacs of Spotted Salamanders "Gaian symbiosis in miniature?" I do so because the crux of my 1990 scientific paper is that it is a remarkable thing indeed that Planet Earth, while open to the sun's energy, must be entirely capable of keeping all of the matter essential for life circulating freely between the oceans, the atmosphere, the soils, the life forms themselves, and the far slower circulation of rocks propelled by plate tectonics. Technically, Earth and its biosphere is a "closed system". In the very early evolution of life, every time some essential element (notably, nitrogen) got stuck somewhere in the cycle, bacteria would evolve a new form of metabolism to "mine" that stuck resource and get it back into circulation.
From my observations in the spring of 2011 at Sallie Pond, I noticed a profound difference in the structural integrity of Spotted Salamander jelly blobs versus the jelly masses laid by various species of frogs and toads. As massive spring rains and winds jostled the denizens of the pond, all the jelly masses except those of the Spotted Salamander tended to disintegrate. As well, there was a much shorter time between egg laying and egg hatching for the smaller species, so they didn't need robust jelly for as long. Hence my hypothesis: Because Spotted Salamander nymphs take so long to develop, a sturdier jelly would have been selected for by evolution. If a jelly mass can hold onto its stick or pond-bottom perch away from the danger of a diminishing and drying shoreline, then as the pond waters swirl, and waters rise and fall with the rains, the jelly mass will not become stranded ashore. The downside, of course, is that the sturdier the jelly, the less porous it is to air transfer. Thus, acquiring symbiotic algae would have given the species an opportunity to fortify its jelly — without diminishing its metabolic rate. Further speculation: Salamander embryos that did not enter into this form of algal symbiosis would have taken longer to develop, given the same robustness of jelly. They would have been "lost to the gene pool" because this trait would be a dangerous disadvantage. Certainly at the Sallie Pond I observed, the danger for slow hatching is that in some years, the ephemeral pools dry up before this large salamander has time to trade its gills for lungs. Stretching out the time for embryo development is thus a bad idea. Why not simply switch from temporary forest ponds to perennial water bodies? The answer is safety from predators. Perennial freshwaters of high enough quality to support salamanders would inevitably carry fish. Fish are dangerous predators for new hatchlings. But in an ephemeral forest pond, Spotted Salamander nymphs are the top aquatic predator!
 
April 1 I collected the smallest Spotted Salamander jelly mass, plus extra pond water, and backpacked it to the cabin. Lo, two hatched by the time I got there, from the jostling. An hour later we left for gigs in Atlanta.After the program, I poured the contents of the bowl back into several jars (as I had added additional plain pond water to the bowl), and my husband and I made the return drive to Lookout Mountain. Upon arrival, Tobey and I immediately walked to the pond and released all the baby salamanders back into the cool waters of home. They had done such fabulous work! I then pulled off a single-egg-sac chunk of one of the untouched egg masses in the pond and put it in my jar to carry back to the cabin. I wanted to have one unstressed nymph to care for in the remaining weeks before we were scheduled to head north.
 
 
This is because Spotted Salamader nymphs are total carnivores. In fact, they have been described as the T. rex of ponds. At first I named my hatchling T. rex, but I soon substituted the name Triceratops. It just looked like Triceratops! See the photo above left with the feathery external gills stretching outwards, like the bony fringe plate that protected Triceratops' neck. In my quest to gather food for my temporary pet, I discovered a whole new world in the pond! And, I was amazed to occasionally see an impossibly tiny polliwog appear overnight in the extra jar of daphnia-and-algae-rich pondwater I kept for restocking Triceratops' home. Apparently, there are amphibian species that lay invisible eggs in the algal masses. Looking down into the jar or through the side, I watched Triceratops a lot. But only twice did I see this lurking predator jut out in an instant and swallow something that had been passing directly overhead. Nonetheless, the daphnia and roundworms I kept adding to the mix tended to disappear. On April 22 I wrote this email to a friend: "In 2 days we leave this paradise, so "Triceratops" will be carried back to its pond to join the other hatchlings. If we continue to get lots of rain, Triceratops will likely mature and maybe live another 20 years. If not, it will be salamander-eat-salamander, as I have read. I have no idea if my guy/gal is bigger for the early hatching, or smaller — as maybe the size of the jar would limit its growth. Its front legs became visible about 5 days ago."
 
ABOVE RIGHT: April 24 - Tobey watches Connie return "Triceratops" to its natal home.
All the remaining viable egg sacs in the pond had long since hatched. Despite best efforts, Connie could locate no "wild" nymphs in samples of nearshore detritus she searched through. These salamander nymphs are, after all, lurkers not swimmers. And perhaps they found deeper waters more to their liking.
MONTHS LATER: Tobey told Connie that the summer produced good rain; the drought that had swept the southeastern United States for several years was in hiatus. Surely, a good many Spotted Salamanders (like the one at the top of this page, which I found 40 feet from a pond in the Finger Lakes area of New York the previous August) had crawled out of Sallie Pond and found their way to abundant fallen logs and rocks. Deep below these surface features they would live the life of a cold-blooded mole — venturing near surface only in the moistest of times.
I'd like to think that Triceratops was among them. If so, my little friend will eventually grow to 8 inches in length — and it could, quite possibly, outlive me. This species is known to live as long as 32 years!
Good luck, Triceratops! May you and your descendants continue to make annual pilgrimages to precious forest pools. And may my own species learn the joys of making pilgrimages to Sacred Sites of the Epic of Evolution!
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