The ancient Phoenicians may be largely forgotten, but they're not gone.
Rome destroyed the Phoenicians' greatest city -- Carthage -- centuries ago, but new genetic studies indicate that as many as one in 17 men living in communities around the Mediterranean may be descended from these ancient mariners. Originating from what is now Lebanon, the Phoenicians were early seafarers and traders who spread their culture, including a love for the color purple, to North Africa, Spain and other countries around the region.
But they seemed to fade from history after their main colony, Carthage, was defeated in a series of wars with Rome. Researchers led by Chris Tyler-Smith of the Wellcome Trust Sanger Institute in England were able to locate a genetic marker for the Phoenicians on the male-only Y chromosome.
First they studied references in the Bible and by Greek and Roman writers to determine where there had been Phoenician cities and colonies. Then the researchers compared the genes of residents in those areas to those of people living in other Mediterranean communities which had not been Phoenician settlements. They were able to find differences on the Y chromosome that occurred only in the Phoenician-settled areas, affecting more than 6 percent of the population there.
"When we started, we knew nothing about the genetics of the Phoenicians. All we had to guide us was history: We knew where they had and hadn't settled. But this simple information turned out to be enough, with the help of modern genetics, to trace a vanished people," Tyler-Smith said in a statement.
Added Daniel Platt, of IBM's Computational Biology Center: "The results are important because they show that the Phoenician settlement sites are marked by a genetic signature distinct from any that might have been left by other trading and settlement expansions through history, or which may have emerged by chance. This proves that these settlements, some of which lasted hundreds of years, left a genetic legacy that persists to modern times."
While it wasn't part of their study, the researchers said they also saw genetic indications of the spread of the Greeks around the Mediterranean. They suggested similar studies may be able to trace the genetic influence of the army of Alexander the Great in Asia and India, the Mongol invasion of Europe and the spread of the Vikings.
The findings are being published online Thursday by the American Journal of Human Genetics. The work was supported by National Geographic and IBM's Genographic Project, an effort to research the history of human migration.
Alpine 'Iceman' May Have Been Last of His Kind
The Neolithic mummy dubbed the Iceman likely has no relatives alive today on his mom's side of the family, finds a new study of the ancient guy's genes. The remains of the Iceman (also called Oetzi, Frozen Fritz and Similaun Man) were discovered accidentally in 1991 by German tourists in the eastern Alps.
Since then, a suite of tests has opened a window into the guy's life and death.
For instance, the Iceman was about 45 years old when he died; he was probably a hunter-gatherer while alive ; he sustained a shoulder injury from an arrow and might have died from head trauma ; and his last meal included unleavened bread and meat. Now, researchers have fast-forwarded genetically from 5,300 years ago, when Oetzi died, to the present to look at whether his maternal lineage is alive and kicking.
It's probably not.
Mom's genes
The research team, led by Franco Rollo of the University of Camerino, Italy, and Luca Ermini working at Camerino and the University of Leeds, England, extracted DNA from the Iceman 's rectum. They analyzed the genome of the cells' energy-making structures, called mitochondria.
"You only get mitochondrial DNA from your mother, and she gets it from her mother, and so on, so it forms an unbroken link all the way back to the common maternal ancestor of all of us," said researcher Martin Richards of the University of Leeds.
The results showed that Oetzi fits in genetically with a particular group of living individuals who share a common ancestral DNA sequence. Over time, different individuals and groups can branch off from the main group, genetically speaking. Oetzi's DNA belonged to a cluster of lineages whose members are still common throughout Europe today.
However, nearly all members of this cluster belong to one of three sub-lineages, or sub-clusters. Oetzi didn't. His DNA placed him on a completely distinct, fourth sub-lineage, for which there are no other members alive today -- or at least none have been found so far. His lineage branched away from his nearest modern relatives about 20,000 years ago. That means Oetzi's maternal lineage is either extremely rare or has died out altogether.
The finding is detailed in this month's issue of the journal Current Biology.
Finding ancestors
The results run counter to past research by Richards and his colleagues, which suggested Oetzi's relatives still exist today in Europe. But the past studied relied on just a short segment of the mitochondrial DNA , unlike the recent study in which the entire mitochondrial genome was analyzed. With less genetic material, as in the first study, fewer mutations show up.
It's these mutations that scientists match up across the genomes of a group of individuals to say whether the group has a common maternal ancestor. With more genetic material, as in the recent study, more mutations show up. And if scientists do find a match between different individuals based on those mutations, there is more certainty that the match-up is real and not some artifact of sampling or just due to chance, Richards said.
While the mitochondrial DNA findings suggest no modern-day Iceman relatives along his maternal line, the results say nothing about whether the Iceman had children, who would have inherited their mitochondrial DNA from their mother. In addition, the number of individuals with sequenced mitochondrial DNA is limited. That means there's a possibility individuals not in the database could hold mitochondrial DNA that matches up with that of the Iceman.
Next, the researchers hope to continue their search for modern-day relatives of the Iceman.
"It would be nice to go and look in the areas where he might have grown up and see whether maybe there is some valley which has lots of related lineages to him," Richards told LiveScience. "That would be very interesting, because it would pin down where he or his family and his ancestors lived in much more detail than we can do at the moment."
The research was funded by global pharmaceutical company Eli Lilly and Co.
A rare reptile with lineage dating back to the dinosaur age has been found nesting on the New Zealand mainland for the first time in about 200 years, officials said Friday. Four leathery, white eggs from an indigenous tuatara were found by staff at the Karori Wildlife Sanctuary in the capital, Wellington, during routine maintenance work Friday, conservation manager Rouen Epson said.
"The nest was uncovered by accident and is the first concrete proof we have that our tuatara are breeding," Epson said. "It suggests that there may be other nests in the sanctuary we don't know of."
Tuatara, dragon-like reptiles that grow to up to 32 inches, are the last descendants of a species that walked the earth with the dinosaurs 225 million years ago, zoologists say. They have unique characteristics, such as two rows of top teeth closing over one row at the bottom.
They also have a pronounced parietal eye, a light-sensitive pineal gland on the top of the skull. This white patch of skin -- called its "third eye" -- slowly disappears as they mature. A native species to New Zealand, tuatara were nearly extinct on the country's three main islands by the late 1700s due to the introduction of predators such as rats. They still live in the wild on 32 small offshore islands cleared of predators.
A population of 70 tuatara was established at the Karori Sanctuary in 2005. Another 130 were released in the sanctuary in 2007. The sanctuary, a 620-acre wilderness minutes from downtown Wellington, was established to breed native birds, insects and other creatures securely behind a predator-proof fence.
Empson said that the four eggs -- the size of pingpong balls -- were unearthed Friday but that there were likely more because the average nest contains around ten eggs. The eggs were immediately covered up again to avoid disturbing incubation.
If all goes well, juvenile tuatara could hatch any time between now and March, she said.
Beneath the tourist gondolas in the remains of a great Aztec lake lives a creature that resembles a monster -- and a Muppet -- with its slimy tail, plumage-like gills and mouth that curls into an odd smile.
The axolotl, also known as the "water monster" and the "Mexican walking fish," was a key part of Aztec legend and diet. Against all odds, it survived until now amid Mexico City's urban sprawl in the polluted canals of Lake Xochimilco, now a Venice-style destination for revelers poled along by Mexican gondoliers, or trajineros, in brightly painted party boats.
But scientists are racing to save the foot-long salamander from extinction, a victim of the draining of its lake habitat and deteriorating water quality. In what may be the final blow, nonnative fish introduced into the canals are eating its lunch -- and its babies.
The long-standing International Union for Conservation of Nature includes the axolotl on its annual Red List of threatened species, while researchers say it could disappear in just five years. Some are pushing for a series of axolotl sanctuaries in canals cleared of invasive species, while others are considering repopulating Xochimilco with axolotls bred in captivity.
"If the axolotl disappears, it would not only be a great loss to biodiversity but to Mexican culture, and would reflect the degeneration of a once-great lake system," says Luis Zambrano, a biologist at the Autonomous University of Mexico, or UNAM.
The number of axolotls (pronounced ACK-suh-LAH-tuhl) in the wild is not known. But the population has dropped from roughly 1,500 per square mile in 1998 to a mere 25 per square mile this year, according to a survey by Zambrano's scientists using casting nets.
It has been a steep fall from grace for the salamander with a feathery mane of gills and a visage reminiscent of a 1970s Smiley Face that inspired American poet Ogden Nash to pen the witticism: "I've never met an axolotl, But Harvard has one in a bottle."
Millions once lived in the giant lakes of Xochimilco and Chalco on which Mexico City was built. Using four stubby legs to drag themselves along lake bottoms or their thick tails to swim like mini-alligators, they hunted plentiful aquatic insects, small fish and crustaceans.
Legend has it that Xolotl -- the dog-headed Aztec god of death, lightning and monstrosities -- feared he was about to be banished or killed by other gods and changed into an axolotl to flee into Lake Xochimilco.
The axolotl's decline began when Spanish conquerors started draining the lakes, which were further emptied over time to slake the thirst of one of the world's largest and fastest-growing cities. In the 1970s, Lake Chalco was completely drained to prevent flooding. In the 1980s, Mexico City began pumping its wastewater into the few canals and lagoons that remained of Xochimilco.
About 20 years ago, African tilapia were introduced into Xochimilco in a misguided effort to create fisheries. They joined with Asian carp to dominate the ecosystem and eat the axolotl's eggs and compete with it for food. The axolotl is also threatened by agrochemical runoff from nearby farms and treated wastewater from a Mexico City sewage plant, researchers say.
Local fisherman Roberto Altamira, 32, recalls when he was a boy, and the axolotl was still part of the local diet.
"I used to love axolotl tamales," he says, rubbing his stomach and laughing. But he says people no longer eat axolotls, mainly because fishermen almost never find them.
"The last one I caught was about six months ago," says Altamira, a wiry gondolier with rope-like muscles from years of poling through Xochimilco's narrow waterways.
Meanwhile, the axolotl population is burgeoning in laboratories, where scientists study its amazing traits, including the ability to completely re-grow lost limbs. Axolotls have played key roles in research on regeneration, embryology, fertilization and evolution.
The salamander has the rare trait of retaining its larval features throughout its adult life, a phenomenon called neoteny. It lives all its life in the water but can breathe both under water with gills or by taking gulps of air from the surface. On a 9-foot-wide canal covered by a green carpet of "lentejilla" -- an aquatic plant that resembles green lentils -- Zambrano's researchers test water quality and search for axolotls. The air smells of sulfur and sewage.
A team member suddenly points to the trademark water ripple of an axolotl, and the crew hurls its net. But they only come up with two tilapia in a sopping-wet mass of lentejilla.
So far, scientists disagree on how to save the creature. But a pilot sanctuary is expected to open in the next three to six months in the waters around Island of the Dolls, so-called because the owner hangs dolls he finds in the canals to ward off evil spirits.
Zambrano proposes up to 15 axolotl sanctuaries in Xochimilco's canals, where scientists would insert some kind of barrier and clear the area of nonnative species. Without carp, the water would clear, and plants the axolotl needs to breed could flourish again, said Bob Johnson, the curator of amphibians and reptiles at the Toronto Zoo.
"If you take the insults away, the lake has an amazing latent potential to heal itself," he said.
Veterinarian Erika Servin, who runs the Mexico City government's axolotl program at Chapultepec Zoo, is studying the possibility of introducing axolotls from the lab into the canals. But more study is needed to make sure the process doesn't lead to diseases and genetic problems from inbreeding.
Xochimilco residents could be another source of resistance. Hundreds of people make a living pulling tilapia from canals or growing flowers, lettuce and vegetables on nearby land. Efforts to remove the fish or shut down polluting farms could face stiff opposition. But while the debate goes on, time is running out. Given its role in research alone, Johnson says, "We owe it to the axolotl to help it survive."
New York City Takes Hunt for Rats Online
The city wants to make sure rats have no place to hide, at least online. A Rat Information Portal, complete with a searchable map of rat inspections and violations, debuted Thursday on the city's Web site. Beyond providing advice on rousting the rodents, the site aims to encourage residents to act as rat watchdogs, using the map to track trouble spots and pressure property owners who are slow to address them.
"It's so they can better understand what's expected of the people in charge but also what they can do to help push it along," said Dan Kass, an assistant commissioner of the city Department of Health and Mental Hygiene.
The rat portal, which also offers photos of rat droppings and tips on choosing an exterminator, is the city's latest move to turn up the heat on the rodents. In recent years, the city has dispatched inspectors with handheld computers to canvass neighborhoods for signs of the vermin, hired a renowned rodent expert and stepped up efforts to evict the pests from parks.
Rats have long been a part of life in the nation's largest city, but some high-profile infestations have put a spotlight on the scurrying vermin. Television footage of rats scampering around a Manhattan KFC/Taco Bell restaurant after closing time in February 2007 became an Internet sensation, leading parent company Yum Brands Inc. to close the location permanently and the city to ramp up restaurant inspections.
Later last year, city officials acknowledged they were fighting a rat problem in the park surrounding City Hall. Kass said the city is seeing encouraging results from its neighborhood-wide inspections, which began in the Bronx last winter. The idea is to check for infestations in an area, instead of react to complaints about individual properties.
Preliminary results show the approach is improving eradication efforts, Kass said.
Health officials aren't the only ones doing their part to combat rats, said a spokesman for the Rent Stabilization Association, which represents the owners of about 1 million city apartments.
Find out more at http://www.nyc.gov/rats
Walter
FOX News, Wellcome Trust Sanger Institute, IBM's Computational Biology Center, American Journal of Human Genetics, University of Camerino, Karori Wildlife Sanctuary, Autonomous University of Mexico, NYC Department of Health and Mental Hygiene.
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