GEOL 388 Field Studies II:
The Natural History of the Galápagos Islands

Introduction: In Darwin's Footsteps

by Thomas R. Holtz, Jr.
Director, College Park Scholars - Earth, Life & Time Program
Department of Geology
August, 2006

The University of Maryland in the wilderness of Rábida Island.

Charles Darwin was one of the most influential thinkers of the last two hundred years. His theory of evolution by means of natural selection not only transformed humanity's concept of the origin of species and the history of life, but also produced a new understanding of our place in the natural world.

The location that most profoundly inspired Darwin's hypothesis, among all the places he visited on the voyage of the H.M.S. Beagle, was the Galápagos Archipelago. Although he was only in the islands for five weeks in late 1835, the diversity of the wildlife and their adaptations to the local physical environment made a great impression on the young naturalist:

    " is astonished at the amount of creative force, if such an expression may be used, displayed on these small, barren, and rocky islands; and still more so, at its diverse yet analogous action on points so near each other. I have said that the Galapagos Archipelago might be called a satellite attached to America, but it should rather be called a group of satellites, physically similar, organically distinct, yet intimately related to each other, and all related in a marked, though much lesser degree, to the great American continent." Charles Darwin, The Voyage of the Beagle, 1845

The islands are the home to a vast array of land and sea bird species, land and marine iguanas found nowhere else, lava lizards and giant tortoises, as well as a diverse and unusual flora. Each species reveals suites of physical and behavioral adaptations to its own particular local environment.

As important as it was for understanding the concept of biological evolution by natural selection, the Galápagos also demonstrate important aspects of the Earth Sciences. Plate tectonics (the greatest geological discovery of the 20th Century) produced the archipelago in an unusual combination of a mantle plume and an oceanic spreading center. These particular set of circumstances is manifested in the various volcanic flows, cones, and other structures that form the framework of the islands. Wind, rain, and waves have produced new landforms via the process of erosion.

Oceanographically, the Galápagos Islands are situated in an interesting meeting point of great ocean currents: the rich cool water upwelling in this region supports a diverse community of fish, marine turtles and mammals, and many invertebrates. The annual cycles of wet and dry seasons on the islands are interrupted on occasion by the El Niño phenomenon.

A small ground finch (male), one of Darwin's finches.

Although most famous for Darwin's investigations in 1835, during the past centuries the Galápagos Archipelago was also home to pirates and whalers, prison colonies and failed utopian communities. In the middle of the 20th Century a new appreciation for the conservation of wildlife led to the establishment of the Charles Darwin Research Station, and ultimately to the transformation of the islands into a National Park of Ecuador and a UNESCO World Heritage Site.

There are few other places on the planet where evolutionary biology, geology and other earth systems sciences, natural history and human society are so obviously integrated. It was for this reason that in the summer of 2004 the directors of the College Park Scholars - Earth, Life & Time program returned once again to the Islands to follow up on the successes of their Summer 2000 and 2002 field courses. This time, the class consisted of a team of thirteen students, who investigated these various aspects of the Galápagos Archipelago. We visited nine of the islands in the Achipelago while travelling on board the power catamaran Millenium.

The power catamaran Millenium off Puerta Egas, Santiago Island.

This website represents the results of their own experiences, observations, and investigations, created to provide an educational resource on these diverse topics. We offer this information so that teachers, students, and explorers of all ages can benefit from our experiences on these Enchanted Islands.

Lizard City!! Marine iguanas on Española.