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Destination: Galapagos Islands Cyber Field Trip

Photo of Lynn Fowler
Q&A with Lynn Fowler

You can learn more about Lynn Fowler in Meet the Team.


Question We have been studying natural selection and how it has led to the development of several subspecies of finches on each island. Do the birds remain on their respective island or do they island hop? If so, can they interbreed with the other finches? (Kenneth Horvath, Middle School Teacher)
Answer Finches sometimes travel between islands when the islands are very close together - they are not strong fliers however, and don't go long distances. Finches can interbreed - or hybridize - and do so on several of the islands where there are many finch species living together.
Question My question is about the Galapagos dove. On which islands are they found? (Sarah Evans, Middle School Student -- I am the daughter of Toni Gower and Bruce Evans who went to the Galapagos with you. I am now in my mom's class.)
Answer The Galapagos dove is a beautiful little bird and is commonest on the islands of Hood, Tower, Pinta, James, Barrington and inside the crater of Fernandina. (Say hello to Toni and Bruce!)
Question What fossils have been found on the islands? What can the fossils tell us about evolution? (John Frank, High School Student)
Answer Since the Galapagos are volcanic we have not found old fossils here. A few remains of extinct finches and rice rats have been found in lava tunnels, but these aren't really old and preserved in rock as true fossils are.
Question How long is lonesome George expected to live and how old is he? (Kristan, Medina, Joe, Dave, Todd, Ryan, Middle School Students, NJ)
Answer Lonesome George is probably about 80 or 90 years old and we think he could live another 100 years!
Question How fast can a penguin swim? (Ken, Evan, Pat, Yasmin, Nikki, Mike, Middle School Students, N.J.)
Answer A penguin can swim at a speed of about 30 kilometer per hour.
Question On your site I read that the giant tortoise's main predator is the Galapagos hawk. How does that little bitty hawk eat that great big turtle, especially when the turtle has a shell?!? (Chris Worley, High School Student)
Answer The Galapagos hawks eat giant tortoise hatchlings, not the huge mature tortoises! Once a tortoise reaches about 10 years of age it has no natural or even introduced predators in Galapagos.
Question Do the sea lions use their whiskers the same way that cats use theirs? (Tyler Hahn, Middle School Student)
Answer Yes, basically sea lions do use their whiskers much as cats do. They are sensitive to touch and probably help the sea lion catch fish.
Question If the animals on the Galapagos Islands aren't scared of humans and other animals, then why do you think the giant Galapagos tortoises still have their shells? (Joe, Andrew, Jimmy, Carrie, Cathy, Ashleigh, Middle School Students, NJ)
Answer The giant tortoises' shell does a whole lot more than just protect his body from predators (which is does help to do when they are little, by the way). It is an integral part of the tortoise's skeletal system and we would need a heck of a long time, plus a selective advantage against shells, to see it disappear.
Question After seeing the effects of El Nino on the marine iguana, what are the expected effects of La Nina on the wildlife in the Galapagos? (Nick Depner, Granite Bay High School)
Answer La Nina will cause drought in the Galapagos, and dry conditions affect all the terrestrial species. Plants don't produce seeds when it doesn't rain. Finches, mockingbirds and all the other land birds can't find much food so they also don't breed very successfully. Little vegetation means the land iguanas don't have much to eat and there are fewer insects (as many of them also feed on plants) hence lava lizards go hungry, and skinny lava lizards means the Galapagos snakes also have less to eat....and so on and so on.
Question Who is responsible for naming the infamous 'Lonesome George'? (Vic Smartalot)
Answer There was a program in the US in the 70's starring George Goble who called himself Lonesome George. This name was given to the lone Pinta male by Dr. Craig MacFarland who was director of the Charles Darwin Research Station at the time that the Pinta "George" was found.
Question Our high school is preparing for our own expedition to the Galapagos in March. We are concerned about the impact that recent volcanic activity has had upon animal visibility and overall population stability. Have there been any noticeable changes? (Matt Hanson, High School Teacher)
Answer Wonderful that you have a high school group coming to Galapagos next year! The recent eruption of Cerro Azul on southern Isabela was not extensive enough to cause much damage to any wildlife populations. Apparently the media reported that we were lifting tortoises away from the eruption site with helicopters - when in reality we were really just moving a few adult tortoises from the flanks of the volcano (they weren't in any danger from the eruption) to the breeding center in the town of Villamil, and taking advantage of the presence of a helicopter in Galapagos during the eruption. So, make plans for that trip as things are great here in the islands and nothing has been changed by the eruption!
Question I realize that there must be laws dealing with your contact with the wildlife and plantlife on the islands. What are some of these guidelines, and how do they help or hinder research on the islands? (Megan McDaniel, High School Student)
Answer The Galapagos Archipelago is one of the most unique and well protected island system and national parks in the world. We use licensed naturalist guides who are trained by the national park and Charles Darwin Station to educate and control our visitors. Park rules include: No collecting of anything (not even a rock, stick or shell), No food on shore, No smoking on shore, No touching or feeding of the animals, Stay on the marked trails and remain with your naturalist guide at all times. To sum these up: Take only pictures and leave only footprints! Scientists who have applied for and received special permits to do research in the islands follow some of the same rules tourists do (for instance it is important that they don't introduce anything to the islands), but are often allowed to handle animals in order to gather scientific data about them. However, all the scientists' camps are outside the visitor areas, so tourists and scientists don't meet on shore. The national park rules are strongly supported by tourist and scientist alike in Galapagos and are an important part of the preservation efforts going on here.
Question With all the visitors and tourists to the islands, are there any provisions being made to keep the islands from being contaminated by invasive species -- such as something that might be tracked in on someone's boots, like seeds from a foreign plant? (Louise Wile)
Answer You are completely correct to worry and ask about the potential of introducing invasive species to Galapagos, and your example of a seed on someone's boot is a good one. We naturalist guides do our best to instruct and educate our groups so that such things will not occur. However, what we must do to protect Galapagos better is to set up a strict quarantine system. Scientists from the Darwin Station have a model of such a quarantine set up and are looking for funding to make it possible for it to be set in effect.
Question How can we help the Galapagos Islands? Is there any foundation or organization where I can donate or help out the endangered animals or environment? (Christina Hudson, Student, Coral Springs, FL)
Answer Thank you for your interest in helping with the preservation of the Galapagos Islands. Why don't you become a "Friend of Galapagos" with a $25 donation given to the Charles Darwin Foundation Inc.? Check our website for more information. We will be grateful for your help, and when you join our foundation we will send you up-to-date information on what has been happening in the Archipelago which will, I am sure, interest you!
Question Why are the Sally Light Foot crabs red and bright orange, they do not blend in with their surroundings, like most of the other animals do? (Joe, Chris, Angie, Sean, Katie, Student, NJ)
Answer Sally Light Foot crabs ARE bright red, blue and orange when they are adults; they are not at all cryptically colored or camouflaged. However, when they are young and are good food for several species of herons and other shore or seabirds they are black and match the lava almost perfectly. This helps them to avoid some of their predators. By the time they are mature and brightly colored, few birds can catch and kill them. They are too fast, have too hard a shell or are just too big for their enemies to handle, so hiding from predators is no longer so important.
Question Can scientists now clone more turtles from Lonesome George, and if so, can they make female turtles? (Jennifer Evans, High School Student)
Answer Cloning can't yet be done with reptiles and can't be done from a male.
Question What ever happened to Lonesome George, the last saddle-backed tortoise? What caused the great reduction in number of these tortoises, since I'm assuming Pinta island is uninhabited. (Paige Sturm, College student and future behavioral ecologist)
Answer Lonesome George is living happily at the Charles Darwin Research Station. He seems to be the last of his species as no other Pinta Island tortoises have been located either on the island of Pinta itself or in zoos and collections around the world. George is not the last of the saddle-backs - just the last saddle-back from Pinta. Goats were introduced to Pinta in 1959 and by 1975 the island was overrun by more than 20,000 goats. To date more than 40,000 goats have been eradicated from Pinta and now only a handful of these introduced animals remain on that island. Pinta is uninhabited but was often visited by ships that were in the Archipelago hunting seals, whales, and fishing. As tortoises can be stored alive in the hold of ships, and eaten at leisure (tortoises can survive in a ship's hold for 2 and occasionally even 3 years without food or water!) they were taken off the islands in the hundreds of thousands during the 1700 and 1800's.
Question If another turtle of Lonesome George's species was found -- a female - wouldn't the species still be doomed due to inbreeding problems? (Amy Kaut, High School Student)
Answer You have a good point that inbreeding would be a grave problem if we did find a female Pinta tortoise to mate with Lonesome George. It is possible that his species would be doomed in any case with only a pair of tortoises to breed. However, the 800 tortoises that we now have living and breeding on the island of Espanola are from 11 females and 3 males -- also a small population and they are just fine. It looks like we aren't going to find a mate or several mates for George so the Charles Darwin Station is considering various option of how to handle his lonely situation.
Question What are the most visited features of the Galapagos Islands and what do you find that the tourists are most interested in seeing? (Travis, Darrin, Josh and Brice, Students)
Answer Bartolome and South Plaza Islands are probably the most visited of all the islands in the Galapagos Archipelago. Both of these are small and extremely picturesque visitor sites. Tourists are always enchanted in particular with the lack of fear that the birds and animals show in Galapagos. Everyone enjoys the chance to get so close to nature in a natural setting and watch behaviors and events that under other circumstances are hidden from us humans.
Question When I show videos of my Galapagos trip to my high school zoology students they ALWAYS are intrigued with the male frigate's re "balloon". The one question that is asked over and over: "What if the air sac is punctured?" When I asked the guide on my trip, she did not know. During evolution, has nature provided the male with a " self-sealing device"? or what? Please answer this seemingly silly question. The kids really need to know and I told them I would find out. Thanks. (Hedy Hoffmann, High School Teacher, Queens, N.Y.)
Answer The pouch is made of skin and like all skin can heal itself when damaged. I have often seen frigates with pouches that have puckers or uneven patterns and this must be the result of healed tears.
Question What precautions are being taken to prevent further introduction of potentially destructive species (such as the Southeast Asian Brown Snake) into the Galapagos? (Jenny Ponisk, Marine Biology Hobbyist, Amateur Birdwatcher)
Answer One of the things we need in Galapagos to protect this fragile island ecosystem from the further introduction of alien species is a quarantine system that would check all cargo and passengers coming into the archipelago by both ships and planes. This year, during the El Nino, frogs made it out to Galapagos! Apparently they traveled in the damp hold of a cargo ship coming from Ecuador and made it to shore with the cargo. Because the Islands were so wet these frogs managed to survive in the town of Puerto Ayora. Hopefully however, as the climate returns to its normal dry conditions the frogs will die off and be unable to establish.

We need to thoroughly check everything that comes into the islands to make sure that not even something as small as an ant arrives! We also need increased public awareness and education about the dangers of bringing species foreign to the islands so that the people who live here won't even be tempted to bring pets, plants and other things that they shouldn't be bringing.
Question How did the animals get on the islands since the islands were formed by volcanoes? Is there a theory about what was the first animal ever to live on the islands? (Eric Allegree and Michael Allen, Middle School Students)
Answer The Galapagos Islands are indeed oceanic, volcanic islands that have never been connected to the mainland by a land bridge. All the species that live on the archipelago had to travel over at least 600 miles of open ocean to arrive to the islands.

Many of the plant species that are now found in Galapagos were probably originally brought here on the wind or by birds (either after having been eaten as a seed by a bird, or coming stuck to their feathers or feet). Reptiles and rice rats apparently came on vegetation rafts - clumps of plants or logs that broke off inland, floated down rivers and, as little islands, floated all the way out from mainland South America to the Galapagos. Seabirds and marine mammals swam out on the ocean currents.

We can't say for certain which species arrived first to Galapagos, but it was undoubtedly one of the species that is now most distinct and different from its original ancestors, For animals, maybe the iguanas or finches and for plants maybe the Scalesia or one of the cactus? I have never heard of any theory that proposes one species as the first to inhabit Galapagos.
Question If Charles Darwin were visiting the Galapagos Islands with you today, would he see essentially the same islands and biological systems he saw 165 years ago? (Berch Carpenter, High School Teacher)
Answer Darwin would see many of the same species today that he saw when he traveled to Galapagos in 1835, but if he visited the four islands that he visited 165 years ago -- San Cristobal, Floreana, Isabela and Santiago -- he would find these islands greatly changed. Many species of plants and animals have been introduced to the archipelago since Darwin was here and some of these are causing serious harm to the fragile island ecosystem.

The four islands where Darwin landed have all had human inhabitants (Santiago is no longer inhabited -- the other three islands still are) and thus have many introduced species. Some of the smaller or remote islands in the archipelago -- for instance Genovesa and Fernandina - are among the most untouched and pristine islands in the world, having no species of introduced plants or animals on them. However, Darwin did not visit either of these islands! Darwin spent over a week camped on the island of Santiago and wrote that he had trouble finding a spot to pitch his tent on that island because there were so many land iguana burrows.

Unfortunately, Darwin would be disappointed if he returned now to Santiago as he would find that the land iguanas are now extinct from that island. Feral pigs and dogs that have been introduced to the islands prey on the fearless land iguanas.
Question Our science book talks about Darwin's finches. A bloodsucking, vampire finch was mentioned. Tell me more! I can't find any info. Thanks for your help. My students are dying to know. (Wendy Walker-Livingston, Middle School Teacher)
Answer There are 13 species of Darwin's finches in Galapagos and a 14th species of Darwin's finch is found on Cocos Island, Costa Rica. The sharp billed ground finch which occurs on Genovesa, Pinta, Santiago, Fernandina, Wolf and Darwin is a "vampire" only on the remote northern islands of Wolf and Darwin. On these islands the sharp billed ground finches have learned to peck at the elbow and base of the tail feathers of boobies and draw blood which they then lap up. (They don't really suck the blood!) This is an important source of food for these birds particularly under drought conditions. Individuals in populations on the other islands listed above have not learned to do this; they feed on seeds and insects like the rest of the Darwin finch species.
Question Are there any species on the Galapagos Islands that are considered endangered? (Jason Timm, Student, Big Bear City, California)
Answer Several of the subspecies (or races) of giant tortoises and several of the populations of the land iguanas are endangered, as are the mangrove finch, the dark-rumped petrel and a couple species of the rice rats. All of these animals and birds are endemic species that are found only in Galapagos and no where else in the world, except for the dark-rumped petrel (also known as the Hawaiian Petrel) which is found in Galapagos and Hawaii.
Question Are there any animals on the Galapagos Islands that have no natural predators? If so, what keeps them from destroying the food chain? (Jeanine Scheidler, Student, Zion, Illinois)
Answer Young tortoises, land iguanas and marine iguanas are occasionally preyed on by the Galapagos hawks -- but as adults these species have few or no natural predators. However, their populations are naturally limited by the availability of food and resources. The harsh climate of the Galapagos Islands serves to keep the populations in check.
Question How big is the smallest island in the Galapagos? How big is the largest? (Ty Cobb, Middle School Student)
Answer Isabela Island - 4588 square kilometers in size -- is by far the largest of the islands in the Galapagos Archipelago. It makes up more than half the total land area -- which is 7882 square kilometers -- of the Archipelago. South Plaza Island -- .13 square kilometers -- is the smallest island that is regularly visited by tourists during a cruise in the islands. However, if you define an island as any land mass that has a single vascular plant on it, then there are about 140 islands in all in the Galapagos and the smallest of these would be very small indeed!
Question Have many species been introduced to the Galapagos Islands since Darwin did his first research there? And have any of these introduced species caused problems to the ecosystems? (Raymond, High School Student)
Answer Hundreds of species of plants and tens of species of insects have been introduced -- some on purpose, some by accident -- to the Galapagos. The large inhabited islands have populations of horses, cattle, donkeys, pigs, goats, dogs, cats, rats and mice. The introduced plants and animals have wrecked havoc with the fragile island ecosystem. During the El Nino an entire new class of animals -- Frogs! -- came on cargo ships and have survived on the island of Santa Cruz during this unusually rainy season. Hopefully they will die out as the islands return to their normal dry conditions. Introduced species are the cause of the major problems that threaten the unique and fragile ecosystem of the Galapagos.
Question What's the record size and age for large tortoises? (Kevin, Student, Big Bear City, California)
Answer Giant tortoises may weigh up to 250 kilos and measure 150 cm over the curve of the carapace. As tortoises are very long lived, it has been hard for us to measure their maximum age in the field. However, we now know that they reach sexual maturity by about 20 years of age and probably live for at least 150-200 years. What is also amazing about giant tortoises is their ability to go for long periods of time without food or water. Information taken from the logs of sealing and whaling vessels that visited the Galapagos during the 1800's show that tortoises could live in the holds of these ships for up to 3 years without food or water! Unfortunately because of this ability we estimate that 100,000 -- 200,000 tortoises were taken from Galapagos in the 1800's, stored in the holds of ships and used as food by sailors.


Scientific American Frontiers
Fall 1990 to Spring 2000
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