Scientists Finally Crack the Sunflower’s Genetic Code

3268zauber via Wikimedia Commons // CC BY-SA 3.0
3268zauber via Wikimedia Commons // CC BY-SA 3.0

Take that, sunflowers. The convoluted genetic code that has thwarted scientists for so long has finally been cracked. Scientists published their findings in the journal Nature.

Sunflowers (Helianthus annuus L.) make compelling research subjects for a number of reasons. Their richly hued faces are both appealing and iconic, figuring in some of the world’s most famous art. Sunflower seeds and sunflower oil are big-deal crops in some parts of the world, in part because the hardy plants can tough it out through drought and other extreme conditions. And the flower heads famously do this:

Previous attempts to dissect the full sunflower genome have all been unsuccessful, thanks to the many long, confusing, and similar-looking chunks of DNA in the plant’s blueprint. We simply didn’t have the technology to make sense of it.

Now we do, after an enormous team of researchers from Canada, France, the United States, and Israel put their brains together. They developed a platform to unspool and identify 3.6 gigabases—that’s 3.6 x 1,000,000,000 base pairs—of sunflower DNA.


3268zauber via Wikimedia Commons // CC BY-SA 3.0

The results trace the evolution of not only the sunflower but of the entire asterid clade, a massive family of more than 75,000 plants including tomatoes, sweet potatoes, petunias, coffee, sesame, lettuce, mint, honeysuckle, olives, and teak trees.

Around 29 million years ago, the sunflower split off and began copying its genome into the tricky patchwork it is today.

“This is one of the most challenging genomes published to date,” senior author Loren Rieseberg of the University of British Columbia said in a statement [PDF]. “Not only have we sequenced sunflower’s genome but we have also built physical and genetic maps of its structure, which increases the genome’s value for research and breeding.”

Bombshell, Victoria’s Secret’s Bestselling Fragrance, Also Happens to Repel Mosquitoes

Dids, Pexels
Dids, Pexels

People love Bombshell, the best-selling fragrance at Victoria’s Secret, for its summery blend of fruity and floral notes. Not everyone is a huge fan, though: As Quartz reports, the perfume is surprisingly good at warding off mosquitoes. In fact, it’s almost as effective as DEET insect repellent, according to the results of a 2014 experiment by researchers at New Mexico State University.

Researchers took 10 products that are commercially available and tested their ability to repel two different species of mosquitoes: the yellow fever mosquito (Aedes aegypti) and the Asian tiger mosquito (Aedes albopictus), both of which are known to transmit diseases like dengue fever, chikungunya, and yellow fever. In doing so, volunteers subjected their own flesh to the test by placing their hands on either side of a Y-shaped tube containing the blood-sucking critters. One hand was covered in a synthetic rubber glove, while the other hand was sprayed with one of the products but otherwise left bare. Researchers recorded which tunnel the mosquitoes flew to, and how long they avoided the other end.

Three of the products contained DEET, while four products didn’t. In addition, there were two fragrances (including Bombshell) and one vitamin B1 skin patch. The DEET products were the most effective, but Bombshell proved to be nearly as good, keeping mosquitoes at bay for roughly two hours.

“There was some previous literature that said fruity, floral scents attracted mosquitoes, and to not wear those,” Stacy Rodriquez, one of the study’s authors, said in a statement. “It was interesting to see that the mosquitoes weren’t actually attracted to the person that was wearing the Victoria’s Secret perfume—they were repelled by it.”

This isn’t the first time a perfume has had an unintended effect on the natural world. It turns out that tigers are obsessed with Calvin Klein’s Obsession for Men cologne, partly because it contains a synthetic version of civetone, a pheromone that's secreted by glands located near a civet’s anus. This substance was once used to create musky fragrances, but nowadays the scent is mostly reproduced in a lab. Still, the fake stuff must be pretty convincing, because big cats go crazy when they catch a whiff of it.

[h/t Quartz]

Mystery Solved: Scientists Have Figured Out Why Some Squirrels Are Black

Rena-Marie/iStock via Getty Images
Rena-Marie/iStock via Getty Images

It can be something of a surprise to see an animal sporting a fresh coat of paint. Blue lobsters occasionally surface after being caught in traps. A pink dolphin was spotted in Louisiana in 2007 (and several times since). In the Chinese province of Shaanxi, a cute brown and white panda greets zoo visitors.

Another anomalous animal has joined their ranks. Black squirrels have been spotted in both the United States and the UK, and now scientists believe they know why.

Like many animals with unusual color schemes, black squirrels are the result of a genetic detour. Researchers at Anglia Ruskin University, Cambridge University, and the Virginia Museum of Natural History collaborated on a project that tested squirrel DNA. Their findings, which were published in BMC Evolutionary Biology, demonstrated that the black squirrel is the product of interspecies breeding between the common gray squirrel and the fox squirrel. The black squirrel is actually a gray squirrel with a faulty pigment gene carried over from the fox squirrel that turns their fur a darker shade. (Some fox squirrels, which are usually reddish-brown, are also black.)

A black squirrel is pictured
sanches12/iStock via Getty Images

Scientists theorize a black fox squirrel may have joined in on a mating chase involving gray squirrels and got busy with a female. The black fur may offer benefits in colder regions, with squirrels able to absorb and retain more heat, giving them a slight evolutionary edge.

In North America, black squirrels are uncommon, with one estimate putting them at a rate of one in every 10,000 squirrels. In 1961, students at Kent State University in Ohio released 10 black squirrels that had been captured by Canadian wildlife authorities. The squirrels now populate the campus and have become the school’s unofficial mascot. Their coloring might help them hide from predators, which might come in handy at Kent State: The campus is also home to hawks.

[h/t The Guardian]

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