Why Galapagos cormorants are flightless


This video from the USA says about itself:

How did the Galapagos cormorant lose half its wings? | UCLA Health Newsroom

UCLA geneticist Alejandro Burga explains how genetic mutations during evolution shortened the Galapagos cormorant‘s wings, leaving it the only one of the 40 cormorant species that’s unable to fly. The changes affect the same genes linked to a human bone disorder characterized by stunted arms and legs. The UCLA discovery may led to new treatments for people with skeletal ciliopathies.

From the University of California – Los Angeles Health Sciences in the USA:

How the Galapagos cormorant lost its ability to fly

Changes to same genes that clipped the bird’s wings also cause human bone disorders

June 1, 2017

Summary: Changes to the genes that shortened the Galapagos cormorant’s wings are the same genes that go awry in a group of human bone disorders characterized by stunted arms and legs, suggests new research. The findings shed light on the genetic mechanisms underlying the evolution of limb size and could eventually lead to new treatments for people with skeletal ciliopathies.

The flightless cormorant is one of a diverse array of animals that live on the Galapagos Islands, which piqued Charles Darwin’s scientific curiosity in the 1830s. He hypothesized that altered evolutionary pressures may have contributed to the loss of the ability to fly in birds like the Galapagos cormorant.

In a new study unraveling the cormorant’s DNA, UCLA scientists discovered genetic changes that transpired during the past 2 million years and contributed to the bird’s inability to fly. Interestingly, when these same genes go awry in humans, they cause bone-development disorders called skeletal ciliopathies.

Published June 2 in the journal Science, the findings shed light on the genetic mechanisms underlying the evolution of limb size and could eventually lead to new treatments for people with skeletal ciliopathies.

“A number of these iconic, salient evolutionary changes occurred in the Galapagos,” said senior author Leonid Kruglyak, chair of human genetics at the David Geffen School of Medicine at UCLA. “Darwin, just by looking at these changes, inferred the process of evolution by natural selection. We now have sophisticated genetic tools to reexamine these classic examples and uncover what happened at the molecular level.”

The Galapagos cormorant, with its short, scraggly wings, is the only one of 40 cormorant species that cannot fly. It is also the largest of the cormorants, and a strong swimmer that dives for its meals of fish.

Researchers, including Darwin, have proposed two evolutionary paths for the loss of flight. In some cases, changes that lead to flightlessness may help birds survive because they enhance their ability to do something else, like swimming — so-called positive selection.

Alternatively, the birds may have lost their ability to fly simply because they didn’t need to migrate or escape from predators. When flying isn’t essential for survival, the mutations that hinder flight can gradually accumulate in the gene pool.

“These two scenarios aren’t mutually exclusive,” said Kruglyak, who is also a Howard Hughes Medical Institute investigator. “You can start down the path because of passive loss of flight but then also have positive selection to keep reducing wings.”

A trip to the Galapagos Islands launched Kruglyak’s interest in the cormorants. Together with first author Alejandro Burga, a postdoctoral fellow in Kruglyak’s lab, they contacted Patricia Parker, a professor of zoological studies at the University of Missouri-St. Louis. She had obtained Galapagos cormorant DNA samples for a previous study and agreed to collaborate on this project.

The researchers sequenced the genomes of flightless cormorants and three other cormorant species to zero in on genetic changes possibly linked to flight. They next used a program capable of determining whether the genetic changes they identified were likely to affect protein structure and function.

Their analyses led them to a gene called CUX1, which was previously linked to shortened wings in chickens. The scientists noticed that Galapagos cormorants possessed a different version of CUX1 than its flying relatives.

“We saw a mutation in this gene that we’ve never seen in other animals,” Burga said. The team confirmed that the changes to the CUX1 gene altered the protein’s function, likely affecting wing size.

The team also found that the flightless cormorants have an abnormally high number of genetic mutations affecting cilia — small, hair-like structures that protrude from cells and regulate everything from normal development to reproduction.

Cilia play a critical role in bone growth. People born with skeletal ciliopathies have shorter limbs, narrowed chests and stunted rib cages — as do the Galapagos cormorants. The UCLA results suggest that CUX1 controls many aspects of cilia, some of which influence bone growth.

Future studies, Kruglyak said, will explore whether other flightless birds, like the ostrich and kiwi, share mutations with the Galapagos cormorant, and whether these genes can help biologists better understand evolution and limb development.

“Loss of flight is something that has taken place in birds frequently,” Kruglyak said. “There’s a pretty rich field trying to understand how all these changes happen and whether common trajectories exist between species.”

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New frog species discovered in Ecuador


This video says about itself:

25 May 2017

In the Amazonian lowlands of Ecuador, scientists discovered a new glassfrog. Hyalinobatrachium yaku is differentiated from all other species by having small, middorsal, dark green spots on the head and dorsum, a transparent pericardium, and a tonal call that lasts 0.27–0.4 s. H. yaku is closely related to Hyalinobatrachium pellucidum.

From ScienceDaily:

New species of frog from the Neotropics carries its heart on its skin

May 29, 2017

Summary: In the Neotropics, there is a whole group of so-called glassfrogs that amaze with their transparent skin covering their bellies and showing their organs underneath. A recently discovered new species from Amazonian Ecuador, however, goes a step further to fully expose its heart thanks to the transparent skin stretching all over its chest as well as tummy.

In the Neotropics, there is a whole group of so-called glassfrogs that amaze with their transparent skin covering their bellies and showing their organs underneath. A recently discovered new species from Amazonian Ecuador, however, goes a step further to fully expose its heart thanks to the transparent skin stretching all over its chest as well as tummy.

The new amphibian is described by a team of scientists led by Dr. Juan M. Guayasamin, Universidad San Francisco de Quito, Ecuador, in the open access journal ZooKeys.

It can also be distinguished by the relatively large dark green spots at the back of its head and the foremost part of the body. Additionally, the species has a characteristic long call.

The new frog is named Hyalinobatrachium yaku, where the species name (yaku) translates to ‘water’ in the local language Kichwa. Water and, more specifically, slow-flowing streams are crucial for the reproduction of all known glassfrogs.

The reproductive behaviour is also quite unusual in this species. Males are often reported to call from the underside of leaves and look after the egg clutches.

Having identified individuals of the new species at three localities, the researchers note some behavioural differences between the populations. Two of them, spotted in the riverine vegetation of an intact forest in Kallana, have been calling from the underside of leaves a few metres above slow-flowing, relatively narrow and shallow streams. Another frog of the species has been observed in an area covered by secondary forests in the Ecuadorian village of Ahuano. Similarly, the amphibian was found on the underside of a leaf one metre above a slow-flowing, narrow and shallow stream.

However, at the third locality — a disturbed secondary forest in San José de Payamino — the studied frogs have been perching on leaves of small shrubs, ferns, and grasses some 30 to 150 cm above the ground. Surprisingly, each of them has been at a distance greater than 30 metres from the nearest stream.

The researchers note that, given the geographic distance of approximately 110 km between the localities where the new species has been found, it is likely that the new species has a broader distribution, including areas in neighbouring Peru.

The uncertainty about its distributional range comes from a number of reasons. Firstly, the species’ tiny size of about 2 cm makes it tough to spot from underneath the leaves. Then, even if specimens of the species have been previously collected, they would be almost impossible to identify from museum collection, as many of the characteristic traits, such as the dark green marks, are getting lost after preservation. This is why the conservation status of the species has been listed as Data Deficient, according to the IUCN Red List criteria.

Nevertheless, the scientists identify the major threats to the species, including oil extraction in the region and the related water pollution, road development, habitat degradation and isolation.

“Glassfrogs presumably require continuous tracts of forest to interact with nearby populations, and roads potentially act as barriers to dispersal for transient individuals,” explain the authors.

Ecuadorean farmers against DynCorp mercenaries


This video from Britain says about itself:

More US militants to help Saudi Arabia’s massacre in Yemen

24 March 2016

The first batch of mercenaries from the private US military firm DynCorp has arrived in the Yemeni city of Aden to replace paid militants from another American company.

Under a USD-3-billion contract between the United Arab Emirates (UAE) and DynCorp, mercenaries from the company are to be deployed to Yemen, where UAE forces are fighting against the Yemeni army and Popular Committees on Saudi orders, Khabar News Agency quoted an official with Yemeni Defense Ministry as saying.

DynCorp International is a USA-based private military contractor. Begun as an aviation company, the company also provides flight operations support, training and mentoring, international … Wikipedia

Headquarters: McLean, Virginia, United States, CEO: James E. Geisler, Founded: 1946, Parent organization: Cerberus Capital Management.

Subsidiaries: DYNCORP INTERNATIONAL OF NIGERIA LLC. The official, who spoke on condition of anonymity, said the first group of the mercenaries recently arrived in the port city of Aden to replace those of Blackwater, a notorious American group now renamed Academi. He added that the new militants included special naval forces, who entered the port of Ras Omran southwest of Aden. DynCorp is a rival of Blackwater, which hires mercenaries and sends them to fight in foreign countries on paid missions.

Blackwater had decided to withdraw from Bab-el-Mandeb region after the Yemeni forces inflicted heavy losses on them. The UAE was forced to bring in the new mercenaries from DynCorp for the same reason. Yemen has been under military attack by Saudi Arabia since late March last year. At least 8,400 people have been killed so far in the aggression and 16,015 others sustained injuries. The strikes have also taken a heavy toll on the impoverished country’s facilities and infrastructure, destroying many hospitals, schools, and factories.

From daily The Morning Star in Britain:

Ecuador small farmers’ day in US court over crop spraying comes closer

Wednesday 5th April 2017

MORE than 2,000 Ecuadorean small farmers began a joint legal action against US military contractor DynCorp on Monday, claiming that it unlawfully invaded Ecuador in 2000 and sprayed farms with toxic chemicals.

International Rights Advocates (IRA), representing the farmers before a jury at Washington District Court, hailed the trial as a positive step.

The group has been trying to take DynCorp to court since 2001 in the face of numerous attempts by the transnational to dismiss the case.

“This is an historic case — a finding against DynCorp will bring justice to the Ecuadorean farmers, who have been waiting a long time to have their day in court,” said IRA executive director Terry Collingsworth.

“A jury will finally get the chance to hear the evidence that DynCorp aerially sprayed a toxic poison that was designed to kill hardy coca plants on thousands of Ecuadorean farms and killed their crops, their animals and caused untold misery for the farmers and their families.”

For the Ecuadorean farmers and their supporters, the trial is long overdue.

Former president Bill Clinton awarded $1 billion in military aid to then Colombian president Andres Pastrana, launching Plan Colombia.

The military campaign was allegedly intended to combat drug traffickers but was directed against the Farc liberation movement and poor rural communities seen as supporting the left-wing guerillas.

DynCorp was hired as part of Plan Colombia to carry out aerial spraying of Colombian farms with glyphosate to eliminate coca crops.

The plaintiffs claim, however, that DynCorp illegally entered northern Ecuador, spraying and causing serious damage to local crops, animals and residents’ health.

New Galapagos giant tortoise species discovery


This video says about itself:

New species of giant tortoise discovered in Galapagos

23 October 2015

The new species is named “Chelonoidis donfaustoi” after a retiring park ranger and is also known as the Eastern Santa Cruz tortoise, lives on the eastern side of the island and is genetically different from tortoises on other islands.

From Wildlife Extra:

New species of giant tortoise discovered in the Galapagos Archipelago

Scientists have discovered there are two species of giant tortoises, not just one, living on the island of Santa Cruz in the centre of the Galapagos Archipelago.

There are two populations of giant tortoises on the island: a large population on the west side in an area known as the “Reserve” and another on the lower eastern slopes around a hill named Cerro Fatal. It was previously believed that group of 250 or so giant tortoises living on the east of the island were the same species as those living on the west, but genetic testing have now proved they are two different species.

“This is a small and isolated group of tortoises that never attracted much attention from biologists previously,” said Dr. James Gibbs, from the SUNY College of Environmental Science and Forestry in Syracuse, New York. “But we now know that they are as distinct as any species of tortoise in the archipelago. Their discovery and formal description will help these tortoises receive the scientific and management attention they need to fully recover.”

The new species has been named Eastern Santa Cruz Tortoise (Chelonoidis donfaustoi) in honour of a longtime Galapagos National Park ranger who spent decades developing methods still used today for breeding endangered tortoises. His name is Fausto Llerena Sánchez, known to his friends and colleagues as Don Fausto.

Don Fausto dedicated 43 years (1971-2014) to giant tortoise conservation as a park ranger for the Galapagos National Park Directorate. He was the primary caretaker at the Tortoise Breeding and Rearing Center on Santa Cruz, which now bears his name. The restoration of several tortoise populations is due in part to Don Fausto’s dedication and efforts.

“It’s to honour Don Fausto for all his dedication and hard work,” Gibbs said. “He devoted his life to saving many critically endangered tortoises through captive breeding. It isn’t easy to breed tortoises in captivity. He didn’t have many resources or much guidance. He figured it out through patient observation, great creativity and intelligence, and tremendous resourcefulness.”

Giant tortoises have been among the most devastated of all Galapagos creatures because of human exploitation, introduced species and habitat degradation. The Giant Tortoise Restoration Initiative is a collaborative project of the Galapagos National Park Directorate, Galapagos Conservancy, Caccone’s group at Yale University and others that works toward the long-term restoration of all Galapagos tortoise populations.

Baby Tortoises Show Up In The Galapagos Islands For The First Time In 100 Years. Read more here.