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Puerto Rican parrots at Rio Abajo (photo by Brendan Borrell)

Last Friday, David Logue, an old friend and biologist from the University of Puerto Rico-Mayagüez took me out to see the island’s imperiled parrots and explain how deciphering their duets could improve efforts to save them.

The Puerto Rican parrot (Amazona vittata) is the only extant parrot native to the United States and is considered one of the most endangered birds in the world. When Christopher Columbus arrived on the island in 1493, there were probably a million Iguaca–as the locals called them–but as colonists chopped down forests, their numbers plummeted. By 1968, just two dozen animals remained.

That’s when the U.S. Forest Service launched its captive breeding project in the El Yunque National Forest. Then, in 1989, the Puerto Rican Department of Natural Resources got in on the act, establishing an aviary at the Rio Abajo State Forest where Logue has brought me to meet his soon-to-be graduate student, Brian Ramos. For the last 11 years, Ramos has been working at the aviary and has nearly mastered the art of avian matchmaking.

After disinfecting our feet, Ramos guided us out a muddy track to the flight cages where the emerald-feathered birds are allowed to mingle. Birds bond with one another by performing a duet–a song-like conversation between the male and female–and Ramos allows the couples with most enthusiastic duets to mate with one another. Currently, the aviary has 198 birds in captivity and is pumping out as many as 30 new chicks each year.

While Ramos has a great record, he thinks he can do better. After all, just 68 birds currently survive in the wild. “We have many fertile pairs, but not all of them are able to raise their chicks,” he says. “I want to have a better understanding of which birds to choose for mating.”

So in the fall, Logue and Ramos will begin filming parrot pairs and recording their duets together to look for subtle clues about how well they are able to work together. Logue, who has studied such duets in black-bellied wrens in Panama, says a key variable in these duets is how quickly the female responds to the male and vice versa. To me, it just sounds like a bunch of random squawking, but Logue insists there’s a logic to this cacophony.

Brendan Borrell will be guest blogging this month. He lives in New York and writes about science and the environment; for Smithsonian magazine and Smithsonian.com, he has covered the ecology of chili peppers, diamonds in Arkansas and the world’s most dangerous bird.

Many Brazilians have a mixed racial background that makes developing medication difficult. Image courtesy of Flickr user robonline

“At my age and with so much mixed blood I no longer know for sure where I belong.  Nobody knows it in these lands … and I believe it will take centuries to know it,” Colombian writer Gabriel Garcia Marquez once wrote. He was referring, of course, to the mixing of genomes that took place in Latin America after the arrival of European colonists and the rise of the African slave trade in the 15th century.

While racial identity is a touchy subject in just about any country, understanding the genetics of mixed populations is becoming a key issue as we discover how drugs can interact with an individual’s genetic makeup. Appropriately, Marquez was quoted by a Brazilian geneticist with a half-German half-Spanish name, Guilherme Suarez-Kurtz, at the 1st Latin American Pharmacogenomics and Personalized Medicine Congress here in Puerto Rico.

During a riveting talk yesterday, he explained how three of the “colors” listed on Brazil’s census forms—white, brown, and black—had a limited relationship with an individual’s genetic background. For instance, Brazilians who labeled themselves “black” ranged from having less than 5 percent to more than 90 percent European ancestry based on their DNA. Such variation becomes important because different populations possess variants of genes that influence how well they are able to metabolize drugs, which impacts the drugs’ effectiveness and, potentially, their safety.

Unfortunately, most of the world’s drugs have been tested primarily on Caucasian populations. Suarez-Kurtz argues that running clinical trials on “admixed” populations in Latin America could be of wider relevance. Other talks examined the level of admixture in different Mexican and Puerto Rican populations, and geneticists are working overtime to understand what this complex heritage means for the future of medicine.

In fact, an organization called PGENI, PharmacoGenetics for Every Nation Initiative, has even sprung up to help developing nations select essential drugs that match their country’s genetic makeup. Kevin Long, the organization’s information guru, told me it is still too expensive to provide personalized medicine to everyone today, but “population-ized” medicine is already becoming a reality.

Brendan Borrell will be guest blogging this month. He lives in New York and writes about science and the environment; for Smithsonian magazine and Smithsonian.com, he has covered the ecology of chili peppers, diamonds in Arkansas and the world’s most dangerous bird.

Spur-thighed tortoises seized by French customs officials.

For as long as people can remember, the spur-thighed tortoise, Testudo graeca graeca has been found on both sides of the Strait of Gibraltar: in North Africa, southern Spain, and a few Mediterranean islands.

An estimated 64.5 percent of children in southern Spain keep or have kept a spur-thighed tortoise in captivity—mostly those that they’ve found in their own backyards. Tortoise-keeping, in other words, is as Spanish as cured ham. Spur-thighed tortoises, however, are not.

As it turns out, no spur-thighed tortoises fossils have ever been found in Spain. Moreover, a paper published last year in Conservation Genetics posits that the tens of thousands of animals now in captivity or roaming the wilds there have their roots in Morocco and Algeria, where the wild populations are much more diverse. Some tortoises may have once lumbered across an ancient land-bridge, but today the endangered critters are ferried across the strait every year with the help of tourists.

On a recent afternoon in the traditional market, or souk, in Marrakech, Morocco, a vendor offered me a string of dozen dried chameleons for a couple of dollars “for my garden” as he put it. Another had a tattered leopard skin on the offing for $60, although I’m sure it could be had for far less. And in a nearby basket, six or seven spur-thighed tortoises clambered atop each other: a pocket-sized souvenir from the timeless wildlife trade.

In Smithsonian’s December issue, Charles Bergman wrote about animal trafficking in the Amazon, but the phenomenon is all the more shocking here in Morocco where such items are sold directly to tourists who probably should know better. Last August, customs officials in France seized 20 tortoises imported from Morocco without the proper paperwork, and in December officials in the United Kingdom nabbed four. In that recent genetic study, one of the tortoises reported to be wild-caught from Spain had the genetic fingerprint indicating it was an introduction from west Morocco.

All this raises questions about how to conserve a “native” species in a region where people may have been moving animals around for tens or even hundreds of thousands of years. The authors of the Conservation Genetics paper suggest that endangered tortoise populations in North Africa and Spain be managed independently because they have each adapted to their local environments. But one could also argue that a little African blood in Spain could give those tortoises the genetic variability they need to survive in the long-term.

Brendan Borrell will be guest blogging this month. He lives in New York and writes about science and the environment; for Smithsonian magazine and Smithsonian.com, he has covered the ecology of chili peppers, diamonds in Arkansas and the world’s most dangerous bird.