Tag Archives: Galapagos Islands

Ping iguala. Photo: Gabriele Gentile

Galapagos islands’ Wolf volcano erupts, threatening unique pink iguanas

This Monday morning, a volcano perched on one of  Ecuador’s Galapagos islands erupted spewing lava on its side and dark plume overhead. The Wolf shield volcano is the highest peak in the Galapagos Islands, reaching 1,707 m. Wolf is situated at the northern end of Isabela Island in the Galapagos, which is barely populated. The authorities have indeed confirmed that the population isn’t at risk, however the local, richly diverse fauna is another thing. The tiny island is the only place in the world that the pink iguana calls home.

Wolf volcano view from satellite. The volcano was named after Theodor Wolf a German geologist who studied the Galapagos Islands in the 19th century. Image: Wikipedia

Wolf volcano view from satellite. The volcano was named after Theodor Wolf a German geologist who studied the Galapagos Islands in the 19th century. Image: Wikipedia

Charles Darwin’s visit to the Galapagos in 1835 is one of the most famous few weeks in the history of science. Historians today seem to agree that those fleeting moments spent on the islands and all the marvelous animals and plants the young Darwin encountered later lend him to become an evolutionist. The world soon followed, though reluctantly at the beginning.

His account of the adventure contained many facts about Galapagos: he described the harsh, desert-like condition of the islands, their trademark giant tortoises, marine iguanas, sea lions and the many sea birds. The ping iguana, however, was not discovered by Darwin. In fact, it was identified as a distinct iguana species only recently, in 2009.

Ping iguala. Photo: Gabriele Gentile

Ping iguala. Photo: Gabriele Gentile

 

“What’s surprising is that a new species of megafauna, like a large lizard, may still be [found] in a well-studied archipelago,” Gabriele Gentile, of Rome’s University Tor Vergata.

If an animal the size of a giant lizard remained elusive to science for all this long, you can safely bet other species unbeknownst to biologists can be found on the islands. Maybe by the hundreds or thousands.

The finch known as Big Bird. Photo: Peter and Rosemary Grant

Biologists witness the birth of a new species before their very eyes

In his magnum opus, ‘On the Origin of Species’, Darwin writes about how evolution and natural selection is omnipresent and working ceaselessly for all living organisms, yet “we see nothing of these slow changes in progress, until the hand of time has marked the lapse of ages.” In other words, evolution works its magic so slowly that to us mortals won’t be able to witness it in action until our nephew’s nephews. Charles Darwin only spent a few months on the Galápagos Islands, however, compared to the past 40 years  British biologists Peter and Rosemary Grant have.

Evolution in action

Peter and Rosemary Grant on Daphne at work. Photo: K.T. Grant

Peter and Rosemary Grant on Daphne at work. Photo: K.T. Grant

If the two sound familiar, you might know them as being featured on the popular science book “The Beak of the Finch“, by Jonathan Weiner. Published in 1994, at a time when 50% of Americans refused to believe in evolution, the book provided an entertaining read on how evolution works. Now, writing for the New York Times, Weiner offers us a precious update of what the married biologist couple have been up to – their discovery is hailed as nothing short of a breakthrough in evolutionary biology.

The finch known as Big Bird. Photo: Peter and Rosemary Grant

The finch known as Big Bird. Photo: Peter and Rosemary Grant

The Grants have visiting the tiny uninhabited island of Daphne Major, the cinder cone of an extinct volcano, each year since 1973. The vigorous duo, now each 77 years of age, would camp in the same spot, near a cave, and exclusively study  the finches in the genus Geospiza – the same birds that offered Darwin key insights that led to the formation of his groundbreaking theory on evolution and natural selection.

They were looking to reconstruct the finches’ evolutionary history, but instead they found something else – the birth of a new species before their very eyes! Weiner writes in his editorial:

“Its own origins date to 1981, when a strange finch landed on the island. He was a hybrid of the medium-beaked ground finch and the cactus finch. He had the sort of proportions that touch our protective feelings: a big head on a stout body. In other words, he was cute. They called him Big Bird.

Hybrids are not unknown among Darwin’s 13 species of finches, but they are rare. Because they evolved so recently, birds of these different species can mate but ordinarily choose not to. (Our own ancestors seem to have felt the same way about Neanderthals.)

Big Bird had a strange song that none of the finch watchers had ever heard. His feathers were a rich, extra-glossy black. He had more tricks in his repertory than his neighbors: He could crack the spiky, troublesome seeds of the Tribulus plant, normally the specialty of the big-beaked ground finch, as well as small seeds favored by the small-beaked ground finch. He could dine on the nectar, pollen and seeds of the cactus, which belongs to the cactus finch.

Big Bird mated with a medium-beak on Daphne. Their offspring sang the new song of Big Bird. And slowly, Big Bird became a patriarch. He lived 13 years, a long time for one of Darwin’s finches. His children, grandchildren and great-grandchildren all sang his song, and they were clannish. They roosted in hearing distance of one another on the slopes of Daphne Major. What’s more, they bred only among their kind, generation after generation.

Big Bird’s lineage has now lasted for 30 years and seven generations.”

The findings top more than 30 years of pain staking observations, providing perhaps some of the best empirical evidence that supports the theory of evolution. Notable figures in the field did not shy away from praising the effort.

“The Grants’ work is possibly the most important research program in evolutionary biology in the last half-century,” Dr. Losos said. “It has reshaped both how we understand evolution and how we study it. Before their work, no one was trying to study evolution in action — now it seems that everyone is.”

The island of Daphne Major. Photo: D. Parer and E. Parer-Cook

The island of Daphne Major. Photo: D. Parer and E. Parer-Cook

While still healthy, sadly the Grants lack their youthful vigor that once helped them return to Daphne Major each year, but their pioneering observations will definitely spark other researchers to follow in their footsteps, either on the same tiny volcanic island or on some of the myriad of tiny ecosystems this planets shelters that are perfectly fit to study evolution at its finest. If you’d like to read more about the Grants’ story, consider reading their latest book authored together – “40 Years of Evolution.”

Giant Galapagos Tortoises in Isabela Island, Galapagos. Adults of large subspecies can weigh over 300 kilograms (660lb) and measure 1.2 meters (4 ft) long. Although the maximum life expectancy of a wild tortoise is unknown, the average life expectancy is estimated to be 200 years.

Giant Galapagos tortoise extinct for 150 years might still be alive

Giant Galapagos Tortoises in Isabela Island, Galapagos. Adults of large subspecies can weigh over 300 kilograms (660lb) and measure 1.2 meters (4 ft) long. Although the maximum life expectancy of a wild tortoise is unknown, the average life expectancy is estimated to be 200 years.

Giant Galapagos Tortoises in Isabela Island, Galapagos. Adults of large subspecies can weigh over 300 kilograms (660lb) and measure 1.2 meters (4 ft) long. Although the maximum life expectancy of a wild tortoise is unknown, the average life expectancy is estimated to be 200 years.

A subspecies of the the giant Galapagos tortoise, Chelonoidis elephantopus, long thought to be extinct for more than 150 years, is now believed to might still exist, scientists say.

Yale University researchers conducted a highly thorough genetic analysis of various Galapagos giant tortoises in the region, which allowed them to speculate that at least a few dozen specimens of the elusive Chelonoidis elephantopus might still be alive!

In 1835 during his antological Beagle expedition to the archipelago, Charles Darwin extensively studied the giant tortoises there, which he reserved a special chapter in his theory of evolution by natural selection. Sadly, just a few years before Darwin set fist foot on the islands, the C. elephantopus, a native of the Floreana Island, was already considered extinct due to excessive whaling – the only signs left behind of its once existence were its giant shells.

The Yale team visited Volcano Wolf on the northern tip of Isabela Island in 2008 and took blood samples from more than 1,600 tortoises. These samples were then compared with other genetic signatures from an extensive genetic database filled with all the known living and extinct species of tortoises. What the reserachers found was nothing short of amazing.

Galapagos islands giant tortoise From the slew of samples, the scientists observed that the C. elephantopus genetic signature was present in 84 Volcano Wolf tortoises, meaning one of their parents was a purebred member of the missing species.  Some hybrids are only 15 years old, so their parents are likely to be alive,  given that they can live to over 100 years old.

“Around Volcano Wolf, it was a mystery – you could find domed shells, you could find saddlebacks, and anything in between,” recounted Gisella Caccone, senior scientist on the new study.

“And basically by looking at the genetic fingerprint of the hybrids, if you do some calculations you realise that there have to be a few elephantopus around to father these animals.

“To justify the amount of genetic diversity in the hybrids, there should be something like 38.”

Alright, but if they were declared extinct and no specimen was sighted since then, how can this giant tortoise subspecies still be roaming  the wild? The leading theory at the moment is that, while the species was wiped out by hunters in its native Floreana Island, the same hunters must have brought them along on their ships. Some tortoises must had made it to shore on Isabela, somehow, and established a presence.

This might sound plausible, but what then of these living specimens – where are they if this is the case? Well, one might think that spotting a giant, slowpoke Galapagos tortoise is an easy feat, however this couldn’t be farther away from the truth. The local vegetation of the Volcano Wolf is hard and lush, making it extremely difficult to explore it. Also, the perfectly camouflaged carapace of the tortoises make them extremely difficult to spot, and only a highly trained eye might have a chance. Dr. Caccone brought in 40 people during her last expedition in search for specimens or even clues of the C. elephantopus existance, however they were forced to stop after a while when supplies ran out.

“To our knowledge, this is the first report of the rediscovery of a species by way of tracking the genetic footprints left in the genomes of its hybrid offspring,” says former Yale postdoctoral researcher Ryan Garrick, now assistant professor at the University of Mississipi.

Even if no purebreds can be found, there’s a good chance that the species can be resurrected through the intensive breeding of hybrids. Curious, isn’t it, how man chases down ghosts of the past he himself slew.

source

357 dead sharks found on illegal fishing ship in Galapagos Park

(c) Galapagos National Park

A patrol by park rangers and an Ecuador navy ship made the largest shark seizure in the country’s history, when they detained a fishing vessel as it was casting its nets 20 miles inside the Galapagos Marine Reserve. On board they found 357 dead sharks.

The government news agency says criminal proceedings will be pursued against the crew of the Ecuadorean fishing boat, in a report which also stats that the boat was detained last Tuesday southeast of Genovesa island inside the marine reserve.

John Bruno, a University of North Carolina marine biologist teaching at the Galapagos Science Center, wrote on his blog, 

“As sad as it is,” he wrote, “I am really encouraged that the park now has the capacity to detect and apprehend illegal fishers in the marine reserve.”

Among the 357 dead sharks, law enforcement officers found 286 bigeye thresher, 22 blue sharks, 40 Galapagos sharks, 6 hammerhead sharks, 2 tiger sharks, and 1 mako shark. Shark poaching is a blooming trade, especially in Ecuador which ships a good chunk of the demand for shark fin soup in Asia. In the Galapagos, illegal shark fishing and finning — the act of cutting off the fins — took off in the late 1990s when the local sea cucumber fishery collapsed. The bodies of sharks are frequently dumped at sea after the fins are cut off.

Currently, 30 fisherman are currently detained and are awaiting their hearing. This may come as little discouragement for those still practicing shark poaching, who make a lot of money worth the risk a fine or a little jail time. The practice has put pressure on many shark species, some of which have become endangered or threatened with extinction.

The Galapagos, made famous by famous naturalist Charles Darwin, was declared an U.N. World Heritage site in 1979.