EVOLUTION’S WORKSHOP: THE GALAPAGOS ISLANDS
The Galapagos Islands are exciting because both the sea and land animals allow you to get up close and personal. When my wife, Carla, and I were there, the blue-footed boobies and the iguanas showed their lack of fear of predators by standing in our footpath, forcing us to go around them. While on land the sea lions might snap at us for getting too intimate, in the water they would swim right around us.
The Galapagos, pinpoints of land on the equator 620 miles off the coast of Ecuador, have been a key player in the understanding of how species evolve. More than any other spot in the world, this natural workshop for the evolution of species has attracted scientists from around the globe. Their research on the flora and fauna of the islands has helped us to understand many of the mysteries of life on earth.
The interest in the Galapagos Islands started with Charles Darwin. Inspired by specimens he collected from the islands on the Voyage of the Beagle in 1831, he developed the theory of the origin of species by natural selection. His insights changed the way we view human’s place in the universe.
Reports from other travelers on the strange animals the ease of meeting them persuaded us to take a 10-day boat trip around the Galapagos Islands. The voyage lived up to the advanced publicity, and we were delighted with how much we saw and experienced.
What are they?
The Galapagos consists of 13 major islands, six small islands and scores of tiny islets. Volcanoes working their way up from 9,000 feet below sea level formed these black lava projections millions of years ago. By wind, wing, swimming and floating on debris, life slowly accumulated on the islands and formed a distinctly different collection of plants and animals from those on the mainland. Because each island supports its own form of tortoise, mocking bird, finch, etc., scientists have been able to learn much about how natural selection works to create new species.
". . .the different islands to a considerable extent are inhabited by a different set of beings. I never dreamed that islands, about fifty or sixty miles apart, and most of them in sight of each other, formed of precisely the same rocks, placed under a quite similar climate, rising to a nearly equal height, would have been differently tenanted . . .. (Darwin, 1845)
The Birds
We saw flamingos, waved albatross and penguins different from those that exist anywhere else in the world. There were three distinct kinds of boobies, and thousands of the masked boobies were nesting on the rough lava surface. We watched frigate birds steal food from other birds who had successfully captured prey. It seems they don’t have enough oil in their feathers to dive, so they watch the diving boobies and grab the fish out of their mouths after they come up from a successful dive. Occasionally, we saw a clumsy dive by a pelican who would come up with a bill filled with small fish.
When we were there, mating, nesting and baby rearing were going on all around us. The male frigate birds were inflating their bright red breast pouches to soccer ball size in hopes of attracting the most beautiful females. Boobies were doing their courting dances and if one got a step, wing flutter, song verse or bill movement wrong, the other would walk off to find someone who knew the correct sequence. Blue-footed boobies who got the courting dance right mate and hatch two eggs after which one of the chicks proceeds to kill the other.
Male frigate birds have a red soccer ball sized bladder on their chests. Females are attracted to the male with the largest bladder.
Some of the gulls had already hatched their eggs. We watched them as the nestlings whined and peeped the proper message that caused the parents to have an irresistible urge to regurgitate predigested food for them.
The famous 13 species of Darwin finches were harder to find. The finches are a small bird and have so much business to take care of that they are in constant motion. It is the variety of their bills that makes them such a valuable lesson in natural selection. The bills are developed as tools for eating special kinds of food, especially during periods when food is scarce.
As you would expect, the different species eat different kind of seeds, insects and plants. But perhaps the most unusual is the vampire finch. During droughts, these small birds land on the tail of a booby and peck at the base of its wing feathers causing it to bleed. They sip the blood and when they leave, others line up and treat it as a blood bank. As gruesome as it sounds, it doesn’t seem to do any great harm to the boobies.
Darwin theorized that evolution usually proceeded very slowly, but further research indicates that extreme changes in conditions such as climate can speed the process. Scientists are seeing that rapid change in the evolution in bacteria mutating in response to antibiotics and in insects responding to pesticides.
The animals
On some islands, there is a profusion of animal life: sea lions in abundance on beaches and in the sea, land and marine iguanas, and if you look closely, darting lava lizards and Sally Lightfoot crabs.
Sea lions were nursing pups that we were warned not to pet. With our smell on them, the mother could reject them and we would have created a starving orphan.
No mammals other than the rice rat made it to the Galapagos, so turtles became the big land animal and existed there by the thousands when sailors first found the islands. The giant turtle’s ability to go months without food and water almost resulted in its extinction.
My wife, Carla, gets up close to the endangered tortoises.
Ships passing by took as many as a hundred at a time into their holds. Placed upside down, they could live for months without food or water, insuring the sailors fresh meat on their long sea voyages. This use of the islands as a meat locker reduced the numbers drastically and helped push some species toward extinction.
There may be as many as 4,500 giant tortoises weighing up to 400 pounds roaming Isabela Island. Several writers have said that some of these giants may be 200 years old. That means there may be ancients among them who were alive when Darwin visited the Galapagos.
The environment destroyers
The first invaders to upset the established ecology were rats off the ships. It is difficult to control rats because they learn quickly to avoid poisons. As a result of the rat’s taste for turtle eggs, the Darwin Research Station collects turtle eggs, hatches them and raises the young turtles to an age when they can defend themselves against rats.
Wild goats, pigs and donkeys introduced by man are also a problem because they eat the food of the endemic species of animals. Although they have been eradicated from some islands, on others obeying Darwin’s rules of natural selection, they have evolved into shy types who will seldom show themselves to hunters.
Most travelers stay on small yachts; we were on this 44 passenger ship.
Touring the islands
As a tourist you will have both wet and dry landings from the dinghy that takes you from the ship to shore. Wet means that you must wade to shore in knee-deep water. Dry means that there is a dock or more likely a rock platform that one steps on from the dinghy. In either case, at first visitors have trouble stepping out of a dinghy that is bouncing up and down on the waves. After a day or two, you get the rhythm and don’t always need a guide on either side of you insuring you don’t fall into the surf.
There is still much raw lava landscape on some islands, and it is difficult to walk across parts of it. You need to be in moderately good condition to really enjoy the trip. You will wonder at times at how life of any sort ever took hold here. Several of the islands are exceptionally barren and seem to consist of little more than raw black rippled lava. Other islands, particularly on their west sides are rich in foliage and, in May, are exceptionally green.
We awoke the first morning on board with the ship rolling from side to side. A number of people were seasick. Everyone was having trouble with their sea legs and occasionally bouncing off the walls. The wide-legged straddle walk was something that took several days to develop. When we got back on land after eight days on the boat, it continued to feel as if the ground under us was gently rocking.
All boats that take tourists around the islands must have trained nature interpreters. About 65,000 people a year come here and they and the boats that carry them are tightly controlled by the park system.
There are 79 boats taking care of the tourist trade in the area with sizes varying from small boats taking eight passengers up to large boats taking a hundred. The number of boats is strictly limited to protect the islands from further destruction. On our boat of 44 passengers, there were 28 staff members, so we were well taken care of. There was even a full time medical doctor on board. The most he had to deal with, however, was some seasickness and a few cases of sunburn.
To protect the islands tourists are limited to 79 boats, some of them quite small.
This is a very relaxed way to travel and you need only casual clothes, bathing suits, and shorts. You also need good walking shoes, sunscreen, a hat and sunglasses. The guides take you on two shore excursions a day, one right after breakfast and one after your noon lunch and siesta. After dinner, you will usually get a presentation from one of your guides on the activities for the next day.
Your traveling companions are likely to have been many places before coming to the Galapagos. It is not on most people’s top 10 places to see unless they have combined it with Macho Picchu in Peru, Quito in Ecuador or a trip down the Amazon River. Travelers find the Galapagos an exciting place to visit and recommend the trip to their friends.
Some popular books that give some good background information are "The Beak of the Finch" by Jonathan Weiner, "Origin, A Biographical Novel of Charles Darwin," by Irving Stone.
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