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

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.”

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What Causes Sinkholes?
Mark Ralston/AFP/Getty Images
Mark Ralston/AFP/Getty Images

This week, a sinkhole opened up on the White House lawn—likely the result of excess rainfall on the "legitimate swamp" surrounding the storied building, a geologist told The New York Times. While the event had some suggesting we call for Buffy's help, sinkholes are pretty common. In the past few days alone, cavernous maws in the earth have appeared in Maryland, North Carolina, Tennessee, and of course Florida, home to more sinkholes than any other state.

Sinkholes have gulped down suburban homes, cars, and entire fields in the past. How does the ground just open up like that?

Sinkholes are a simple matter of cause and effect. Urban sinkholes may be directly traced to underground water main breaks or collapsed sewer pipelines, into which city sidewalks crumple in the absence of any structural support. In more rural areas, such catastrophes might be attributed to abandoned mine shafts or salt caverns that can't take the weight anymore. These types of sinkholes are heavily influenced by human action, but most sinkholes are unpredictable, inevitable natural occurrences.

Florida is so prone to sinkholes because it has the misfortune of being built upon a foundation of limestone—solid rock, but the kind that is easily dissolved by acidic rain or groundwater. The karst process, in which the mildly acidic water wears away at fractures in the limestone, leaves empty space where there used to be stone, and even the residue is washed away. Any loose soil, grass, or—for example—luxury condominiums perched atop the hole in the ground aren't left with much support. Just as a house built on a weak foundation is more likely to collapse, the same is true of the ground itself. Gravity eventually takes its toll, aided by natural erosion, and so the hole begins to sink.

About 10 percent of the world's landscape is composed of karst regions. Despite being common, sinkholes' unforeseeable nature serves as proof that the ground beneath our feet may not be as solid as we think.

A version of this story originally ran in 2014.

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DNA Analysis of Loch Ness Could Reveal the Lake's Hidden Creatures
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iStock

Stakeouts, sonar studies, and a 24-hour video feed have all been set up in an effort to confirm the existence of the legendary Loch Ness Monster. Now, the Associated Press reports that an international team of scientists will use DNA analysis to learn what's really hiding in the depths of Scotland's most mysterious landmark.

The team, led by Neil Gemmell, who researches evolutionary genetics at the University of Otago in New Zealand, will collect 300 water samples from various locations and depths around the lake. The waters are filled with microscopic DNA fragments animals leave behind as they swim, mate, eat, poop, and die in the waters, and if Nessie is a resident, she's sure to leave bits of herself floating around as well.

After extracting the DNA from the organic material found in the water samples, the scientists plan to sequence it. The results will then be compared to the DNA profiles of known species. If there's evidence of an animal that's not normally found in the lake, or an entirely new species, the researchers will hopefully spot it.

Gemmell is a Nessie skeptic, and he says the point of the project isn't necessarily to discover new species. Rather, he wants to create a genetic profile of the lake while generating some buzz around the science behind it.

If the study goes according to plan, the database of Loch Ness's inhabitants should be complete by 2019. And though the results likely won't include a long-extinct plesiosaur, they may offer insights about other invasive species that now call the lake home.

[h/t AP]

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