How an 18th-Century Mutiny May Help Explain Migraine Headaches

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On April 28, 1789, Fletcher Christian and 18 other sailors aboard the HMS Bounty wrested control of the ship from their commanding officer, Lieutenant William Bligh. The mutineers sent Bligh and the members of the crew loyal to him off in a lifeboat in the South Pacific, then set sail to some nearby islands for new lives in a tropical paradise. Over 220 years later, their actions may help researchers unlock the mysteries of the migraine.

A 1,222 Hour Tour

Without charts or a compass, and relying only on a quadrant and his pocket watch, Bligh navigated the lifeboat on a 47-day, 3,618-nautical-mile voyage and safely landed at Timor in the Dutch East Indies. From there he returned to England, two years after he left, and reported the mutiny. He eventually achieved the rank of Vice Admiral of the Royal Navy.

Meanwhile, the mutineers didn’t fare as well. They first attempted to settle on the island of Tubai, but abandoned it after three months of near constant harassment and attack by the natives. Some of the men settled in Tahiti, and the rest moved on to Pitcairn Island, where they burned the ship in what is now called Bounty Bay.  As the mutineers settled into island life, the Crown dispatched the HMS Pandora to retrieve the men and bring them home for trial. The Pandora arrived at Tahiti in early 1791 and 14 of the mutineers were arrested within a few weeks. The ship collided with a part of the Great Barrier Reef during its return trip, losing 31 crew and four of the prisoners, but the remaining ten mutineers eventually made it back to England, where they were tried in a naval court.

The mutineers on Pitcairn managed to avoid detection. Some of them married natives or Tahitians who had hopped aboard the boat when it stopped there. They started families. By 1855, they numbered around 200, and the 88 acres of usable land on the island could no longer sustain the population. Queen Victoria provided some relief and granted the mutineers' descendants Norfolk Island, a former penal colony a few thousand miles west. The next year, they abandoned Pitcairn and settled their new home. Some eventually went back to Pitcairn, and today about 50 people live there. All but a handful -- the pastor, the schoolteacher, and few others -- are direct descendants of the mutineers. The rest stayed at Norfolk, and today’s inhabitants include approximately 1,000 Bounty descendants, about half the island’s population.

No Day at the Beach

Life on Pitcairn and Norfolk can be tough. The only real way to reach Pitcairn is by boat, and storms and rough waters have derailed many of its thrice-annual supply ships. Mail service takes approximately three months, and for medical attention, islanders have to make a several-thousand-mile trip by boat to a New Zealand hospital. Norfolk, which eventually became an external territory of Australia, recently saw a drop in tourism and had to petition the Australian government for financial aid in 2010. As a result, the islanders had to pay income tax for the first time in their history.

And the Bounty descendants on both islands have another problem: headaches.

Migraine affects ~12?% of the Caucasian population worldwide, but among Bounty descendants, the number jumps to 23%, with approximately 12% of males and 33% of females afflicted. This prevalence, combined with their history and living situation, makes the children of the mutiny very attractive to scientists.

Migraine has a strong genetic basis but it’s what medical researchers call a “multifactorial disorder,” meaning that it involves a combination of genes plus environmental triggers, which makes it difficult to study. Two hundred years of geographic isolation, well-kept genealogical records, and restrictions on immigration have left Norfolk and Pitcairn Islands with relatively genetically homogeneous populations where environmental and genetic diversity is reduced enough for effective gene mapping studies, and the islanders are an ideal study sample for studying migraine.

X Marks the Spot?

A team of genomics researchers at Griffith University in Queensland recently studied the islanders at Norfolk, and confirmed earlier research suggesting that at least part of migraine’s genetic cause could be hidden on the X chromosome. Their analysis of the genetics of 377 Bounty descendants associated two mutations on the X chromosome with migraine, which helps explain its increased prevalence among women. Their results also implicated a few other genes with functions as varied as RNA packaging, cell change regulation, protein folding and lipid assembly. They’re now looking harder at these genes and trying to figure out where things are going wrong.

They also think that there’s more where this came from, and that even more genes -- dozens or maybe hundreds -- are involved. More studies like this could eventually isolate other potential migraine susceptibility genes and build up a catalogue of them that could paint a decent picture of the underlying biological pathways of migraine inheritance and susceptibility. In turn, that would help doctors develop better means of migraine diagnosis and treatment, and relieved migraine sufferers might ultimately be able to thank Bligh’s angry crew for putting an end to their misery.

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These Sparrows Have Been Singing the Same Songs for 1500 Years
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Swamp sparrows are creatures of habit—so much so that they’ve been chirping out the same few tunes for more than 1500 years, Science magazine reports.

These findings, published in the journal Nature Communications, resulted from an analysis of the songs of 615 adult male swamp sparrows found in six different areas of the northeastern U.S. Researchers learned that young swamp sparrows pick up these songs from the adults around them and are able to mimic the notes with astounding accuracy.

Here’s what one of their songs sounds like:

“We were able to show that swamp sparrows very rarely make mistakes when they learn their songs, and they don't just learn songs at random; they pick up commoner songs rather than rarer songs,” Robert Lachlan, a biologist at London’s Queen Mary University and the study’s lead author, tells National Geographic.

Put differently, the birds don’t mimic every song their elders crank out. Instead, they memorize the ones they hear most often, and scientists say this form of “conformist bias” was previously thought to be a uniquely human behavior.

Using acoustic analysis software, researchers broke down each individual note of the sparrows’ songs—160 different syllables in total—and discovered that only 2 percent of sparrows deviated from the norm. They then used a statistical method to determine how the songs would have evolved over time. With recordings from 2009 and the 1970s, they were able to estimate that the oldest swamp sparrow songs date back 1537 years on average.

The swamp sparrow’s dedication to accuracy sets the species apart from other songbirds, according to researchers. “Among songbirds, it is clear that some species of birds learn precisely, such as swamp sparrows, while others rarely learn all parts of a demonstrator’s song precisely,” they write.

According to the Audubon Guide to North American Birds, swamp sparrows are similar to other sparrows, like the Lincoln’s sparrow, song sparrow, and chipping sparrow. They’re frequently found in marshes throughout the Northeast and Midwest, as well as much of Canada. They’re known for their piercing call notes and may respond to birders who make loud squeaking sounds in their habitat.

[h/t Science magazine]

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10 Scientific Benefits of Being a Dog Owner
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The bickering between cat people and dog people is ongoing and vicious, but in the end, we're all better off for loving a pet. But if anyone tries to poo-poo your pooch, know that there are some scientific reasons that they're man's best friend.

1. YOU GET SICK LESS OFTEN.

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If cleaning commercials are to be believed, humanity is in the midst of a war against germs—and we shouldn't stop until every single one is dead. In reality, the amount of disinfecting we do is making us sicker; since our bodies are exposed to a less diverse mix of germs, our entire microbiome is messed up. Fortunately, dogs are covered in germs! Having a dog in the house means more diverse bacteria enters the home and gets inside the occupants (one study found "dog-related biodiversity" is especially high on pillowcases). In turn, people with dogs seem to get ill less frequently and less severely than people—especially children—with cats or no pets.

2. YOU'RE MORE RESISTANT TO ALLERGIES.

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While dog dander can be a trigger for people with allergies, growing up in a house with a dog makes children less likely to develop allergies over the course of their lives. And the benefits can start during gestation; a 2017 study published in the journal Microbiome found that a bacterial exchange happened between women who lived with pets (largely dogs) during pregnancy and their children, regardless of type of birth or whether the child was breastfed, and even if the pet was not in the home after the birth of the child. Those children tested had two bacteria, Ruminococcus and Oscillospira, that reduce the risk of common allergies, asthma, and obesity, and they were less likely to develop eczema.

3. YOU'LL HAVE BETTER HEART HEALTH.

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Everything about owning a dog seems to lend itself to better heart health. Just the act of petting a dog lowers heart rate and blood pressure. A 2017 Chinese study found a link between dog ownership and reduced risk of coronary artery disease, while other studies show pet owners have slightly lower cholesterol and are more likely to survive a heart attack.

4. YOU GET MORE EXERCISE.

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While other pets have positive effects on your health as well, dogs have the added benefit of needing to be walked and played with numerous times a day. This means that many dog owners are getting 30 minutes of exercise a day, lowering their risk of cardiovascular disease.

5. YOU'LL BE HAPPIER.

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Dog owners are less likely to suffer from depression than non-pet owners. Even for those people who are clinically depressed, having a pet to take care of can help them out of a depressive episode. Since taking care of a dog requires a routine and forces you to stay at least a little active, dog owners are more likely to interact with others and have an increased sense of well-being while tending to their pet. The interaction with and love received from a dog can also help people stay positive. Even the mere act of looking at your pet increases the amount of oxytocin, the "feel good" chemical, in the brain.

6. YOU HAVE A MORE ACTIVE SOCIAL LIFE.

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Not only does dog ownership indirectly tell others that you're trustworthy, your trusty companion can help facilitate friendships and social networks. A 2015 study published in PLOS One found that dogs can be both the catalyst for sparking new relationships and also the means for keeping social networks thriving. One study even showed that those with dogs also had closer and more supportive relationships with the people in their lives.

7. YOUR DOG MIGHT BE A CANCER DETECTOR.

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Your dog could save your life one day: It seems that our canine friends have the ability to smell cancer in the human body. Stories abound of owners whose dogs kept sniffing or licking a mole or lump on their body so they got it checked out, discovering it was cancerous. The anecdotal evidence has been backed up by scientific studies, and some dogs are now trained to detect cancer.

8. YOU'LL BE LESS STRESSED AT WORK.

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The benefits of bringing a dog to work are so increasingly obvious that more companies are catching on. Studies show that people who interact with a pet while working have lower stress levels throughout the day, while people who do not bring a pet see their stress levels increase over time. Dogs in the office also lead to people taking more breaks, to play with or walk the dog, which makes them more energized when they return to work. This, in turn, has been shown to lead to much greater productivity and job satisfaction.

9. YOU CAN FIND OUT MORE ABOUT YOUR PERSONALITY.

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The kind of dog you have says a lot about your personality. A study in England found a very clear correlation between people's personalities and what type of dogs they owned; for example, people who owned toy dogs tended to be more intelligent, while owners of utility dogs like Dalmatians and bulldogs were the most conscientious. Other studies have found that dog owners in general are more outgoing and friendly than cat owners.

10. YOUR KIDS WILL BE MORE EMPATHETIC.

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Though one 2003 study found that there is no link between pet ownership and empathy in a group of children, a 2017 study of 1000 7-12 year olds found that pet attachment of any kind encouraged compassion and positive attitudes toward animals, which promoted better well-being for both the child and the pet. Children with dogs scored the highest for pet attachment, and the study notes that "dogs may help children to regulate their emotions because they can trigger and respond to a child's attachment related behavior." And, of course, only one pet will happily play fetch with a toddler.

A version of this story originally ran in 2015.

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