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5 Ways Plants Communicate

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You may not think of plants as particularly chatty or active organisms, but they’re not as passive as they might seem. Plants can’t run away, so they have to develop other strategies to stay alive, as James Cahill, an environmental plant ecologist at the University of Alberta, explains in “What Plants Talk About,” a documentary from the PBS show NATURE. They’ve evolved the use of chemicals to communicate with insects and each other in order to thrive. Here are five behaviors that show how active plants can be. 

1. Plants can call for help

When you inhale the sweet smell of freshly mown grass or cut flowers, what you’re actually smelling is the plant’s distress call. “It’s the plant's way of crying out for help,” Cahill says. The scent attracts insects that will eat the pests currently munching on their plant-bodies. For instance, the wild tobacco plant can identify a hornworm caterpillar by its saliva. When attacked by this caterpillar, the tobacco plant emits a chemical signal that appeals to the insect’s enemies. Within hours, caterpillar predators like the big-eyed bug show up, ideally driving the pest away. 

2. Plants can eavesdrop

Plants can eavesdrop on the chemical signals of their brethren, and sometimes respond to another plant’s SOS cry by ramping up their own defenses proactively, knowing that a hungry insect is nearby. 2013 review found 48 studies support the idea that plants increase their defenses after their neighbors are damaged. For instance, when wounded by a hornworm, sagebrush releases defensive proteins called trypsin proteinase inhibitors (TPIs), which prevent the insect from digesting protein and stunt its growth. When neighboring plants—even other species—are exposed to the chemical signals of damaged sagebrush, they begin readying their defenses. Wild tobacco, scientists found, begins prepping to make these TPIs when it senses a distress call from sagebrush, giving it a head start on defending itself if the caterpillar comes calling. 

3. Plants can defend their territory 

Plants compete with each other for sunlight, jostling for position among their neighbors. They also can push out competition in other ways. The invasive knapweed plant—native to Eastern Europe but wrecking havoc on U.S. grasslands—has roots that release certain chemicals to help the plant take in nutrients from the soil. Those same chemicals also kill off native grasses. Thus, the knapweed ends up taking over large territories and killing off its competitors, much like some animals do. Some plants, however, have formed a defense. Lupin roots secrete oxalic acid, which forms a protective barrier against the toxic chemicals given off by knapweed. Lupin can even protect other plants in its vicinity from falling prey to the invasive species. 

4. Plants can recognize their siblings 

Plants can sense when other plants are growing around them. This helps them compete for resources like sunlight, growing more if another plant is shading them, for instance. But like animals, they tend to recognize and support their kin. In an experiment with sea rocket, a plant that often grows close together with its siblings, plants that were grown in pots with relatives had more restrained root growth than plants grown with random strangers. The plants in the stranger condition grew more roots in order to better compete for food, whereas the sibling plants were more considerate of each other’s needs. Further experiments showed that sibling plants recognize each other via chemical signals.  

5. Plants can communicate with mammals

Plants go out of their way to attract more than just insects. A carnivorous pitcher plant native to Borneo has evolved to hijack bat communication systems, turning the bats’ echolocation to its advantage. According to a new study in Current Biology, Nepenthes hemsleyan has a concave structure that is specially suited to reflect bat echolocation, helping the bats find the plant. The bats roost in the pitcher plant, and provide important nutrients by way of the bat guano that gets distributed in the soil nearby.   

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Space
Look Up! Residents of Maine and Michigan Might Catch a Glimpse of the Northern Lights Tonight
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The aurora borealis, a celestial show usually reserved for spectators near the arctic circle, could potentially appear over parts of the continental U.S. on the night of February 15. As Newsweek reports, a solar storm is on track to illuminate the skies above Maine and Michigan.

The Northern Lights (and the Southern Lights) are caused by electrons from the sun colliding with gases in the Earth’s atmosphere. The solar particles transfer some of their energy to oxygen and nitrogen molecules on contact, and as these excited molecules settle back to their normal states they release light particles. The results are glowing waves of blue, green, purple, and pink light creating a spectacle for viewers on Earth.

The more solar particles pelt the atmosphere, the more vivid these lights become. Following a moderate solar flare that burst from the sun on Monday, the NOAA Space Weather Prediction Center forecast a solar light show for tonight. While the Northern Lights are most visible from higher latitudes where the planet’s magnetic field is strongest, northern states are occasionally treated to a view. This is because the magnetic North Pole is closer to the U.S. than the geographic North Pole.

This Thursday night into Friday morning is expected to be one of those occasions. To catch a glimpse of the phenomena from your backyard, wait for the sun to go down and look toward the sky. People living in places with little cloud cover and light pollution will have the best chance of spotting it.

[h/t Newsweek]

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The North Face
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The North Face's New Geodesic Dome Tent Will Protect You in 60 mph Wind
The North Face
The North Face

You can find camping tents designed for easy set-up, large crowds, and sustainability, but when it comes to strength, there’s only so much abuse a foldable structure can take. Now, The North Face is pushing the limits of tent durability with a reimagined design. According to inhabitat, the Geodome 4 relies on its distinctive geodesic shape to survive wind gusts approaching hurricane strength.

Instead of the classic arching tent structure, the Geodome balloons outward like a globe. It owes its unique design to the five main poles and one equator pole that hold it in place. Packed up, the gear weighs just over 24 pounds, making it a practical option for car campers and four-season adventurers. When it’s erected, campers have floor space measuring roughly 7 feet by 7.5 feet, enough to sleep four people, and 6 feet and 9 inches of space from ground to ceiling if they want to stand. Hooks attached to the top create a system for gear storage.

While it works in mild conditions, the tent should really appeal to campers who like to trek through harsher weather. Geodesic domes are formed from interlocking triangles. A triangle’s fixed angles make it one of the strongest shapes in engineering, and when used in domes, triangles lend this strength to the overall structure. In the case of the tent, this means that the dome will maintain its form in winds reaching speeds of 60 mph. Meanwhile, the double-layered, water-resistant exterior keeps campers dry as they wait out the storm.

The Geodome 4 is set to sell for $1635 when it goes on sale in Japan this March. In the meantime, outdoorsy types in the U.S. will just have to wait until the innovative product expands to international markets.

[h/t inhabitat]

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