The Galapagos Islands – A Brief Introduction

Origin of the Name Galapagos

The Galapagos Islands were discovered on March 10, 1535, when the Bishop of Panama, Friar Tomas de Berlanga, was blown off course while sailing to Peru. Cartographers Ortelius and Mercator included the islands on their world map of 1570. The islands were labelled Insulae de los Galopegos, Islands of the Turtles.

Philologists believe the word galápago is derived from the pre-Roman Spanish calappacea or calappaccu which are cognate with the English word, carapace. In Early Modern Spanish of the 16th Century, galápago signified turtle, tortoise or terrapin. Today, the Spanish word galápago is used specifically to classify several species of terrapin.

Legend has it that 16th Century Spanish sailors named the giant tortoises galápagos after their resemblance to a particular type of saddle. (Confusion also comes from the similarity to the Spanish word galopar, to gallop.) This apocryphal story ignores the fact that the Galapago Saddle is actually a type of English light saddle first noted in the mid-1800s.

Bartolome Island, Galapagos Islands

The stark volcanic landscape of Bartolome Island, Galapagos Islands

Formation of the Galapagos Islands

Home to unique species of flora and fauna, the Galapagos Islands are located on the Equator in the Pacific Ocean, 1000km from the Ecuadorian coast. Having formed from a volcanic hotspot, the result of tectonic plate separation, the 19 islands of the Galapagos are unique in that they have never been part of any other landmass.

To the west of the archipelago, the islands are born by a combination of volcanic and seismic activity. The younger western islands of the archipelago are mountainous, featuring active volcanoes and rugged, barren terrain. The older islands to the east are flat, green and forested and are gradually sinking beneath the ocean’s surface.  Due to continental drift, the islands gradually move to the southeast at a rate of approximately 3 inches per year.

The entire archipelago is an island-making conveyor belt running from the northwest where the islands erupt from beneath the sea to the southeast where they will succumb to the waves. The Galapagos Islands that we visit today are only the latest in a long sequence of islands which, over millennia, have risen from and fallen into the ocean.

Animals of the Galapagos

The Galapagos Islands are positioned at the confluence of three major ocean currents which throughout the year bring warm water along the equator (Cromwell Current and South Equatorial Current) and cold water from the south (Humboldt Current). The combination of geological and climatic influences has resulted in the astonishing biodiversity for which the islands are famous.

The Galapagos Penguin is the only species of penguin found in the northern hemisphere and which breeds in the tropics.

The Marine Iguanas of the Galapagos are the only marine lizard species in existence.

The Flightless Cormorant is free of land predators and with little need to fly, over time it has evolved stunted wings which are incapable of flight.

Finches throughout the islands have evolved beaks of varying sizes and shapes to facilitate consumption of island-specific foodstuffs.

Giant Tortoises have evolved different shell shapes on different islands of the archipelago. One subspecies, predominantly found in drier locations, has a high neck arch which enables the tortoises to extend their necks and feast on low-hanging tree branches.

Giant Tortoise, Galapagos Islands

The Giant Tortoise – Namesake of the Galapagos Islands

Charles Darwin and The Origin of Species

In 1835, during his expedition on the HMS Beagle, young geologist and biologist Charles Darwin visited the Galapagos Islands. Fascinated by the relatively young age of the Galapagos Islands, Darwin’s observations of the similarities between species, particularly mockingbirds and finches, likely inspired his initial musings on evolution.

Influenced by Lyell’s theories on geological time and Malthus’s theories on population and the struggle for survival, on the journey back to England, Darwin began formulating a theory which was to revolutionize the world. His theory was that all species – including humans – were not “fixed” but had evolved over time. His work refuted the commonly-held belief that all life on earth had been created by a deity.

Anticipating the reaction that his theory would receive from friends and colleagues within the scientific community, Darwin took great pains to ensure the accuracy of supporting evidence for his work.

The catalyst which finally prompted Darwin to publish an abstract of his work was a letter from scientist Alfred Russell Wallace which outlined his own independently-developed theory of natural selection.  Darwin was encouraged by his friend Lyell, to publish his work immediately so that his work was not eclipsed by Wallace’s planned publication. Today, both Darwin and Wallace are considered co-founders of the theory of evolution by natural selection.

In 1859, more than 20 years after he had visited the Galapagos Islands, Darwin published his masterwork: On the Origin of Species by Means of Natural Selection. In subsequent editions, it was entitled The Origin of Species. Since publication of the first edition, the book has never been out of print.

The idea that “man had evolved from apes” and not divine creation was a notion ill-received by the church and soon after the publication fierce debates raged between scientists and Creationists. They continue to this day.