During our journey in the Galapagos, I was reading Charles Darwin’s journal from when he visited here, and comparing notes with this particular fellow traveler has given me some context in which to place my own experiences. Interestingly, when Darwin left on his voyage, he did so as a naturalist whose main interest was in the field of geology. During his time abroad, however, he could not help but focus his attention on the amazing organisms of the lands he visited. For myself, I may be having a similar, but opposite, experience. Coming from a biological background, I am coming to realize how much of what makes the Galapagos so amazing is its striking geology. The volcanic islands rise up out of seas in the eastern tropical Pacific in which rain is scarce. When air passes over the tall mountains, however, a lot of water condenses, feeding lush cloud forests. In contrast, the lower zones of the islands are arid; only the hardiest cacti and other desert plants, as well as a number of stalwart giant reptiles, eke out an existence here. The barren landscape, frequently repaved by new lava flows, is craggy and stark. But perhaps some water does flow down through the arid zone, but out of reach of light and thus the plants, in deep fissures and recesses in the rough new rock. When this freshwater reaches the coast, however, it is welcomed by mangroves, which in some places grow much taller than expected in such an arid climate. Perhaps subterranean freshwater flow from the mountaintops helps support the oases of mangrove growth situated between the barren desert and the open ocean. Fascinating questions about the natural world can be found everywhere in this amazing place—enough to spend a lifetime exploring. Yet, Darwin only had a few months here, and I have just a few weeks. There’s no time to waste!—back to the field!
Author: Matthew Coasta
PhD student, SIO
Matthew Costa is a Regents Fellow 2013-4 and NSF Graduate Research Fellow 2014-present, and is pursuing a Ph.D. in biological oceanography as part of the Gulf of California Marine Program. He is interested in community ecology, biodiversity and functional diversity, and coastal ecosystem processes and services. His research focuses on carbon storage in sediments of the mangrove forests in the southern Gulf of California. Prior to study at SIO, he completed a B.A. in Ecology and Evolutionary Biology at Princeton University studying mangrove species zonation in Bermuda.