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Addictive Drugs That Are Actually Pesticides

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From coca leaves to coffee beans, people use plants to produce many of the most popular drugs in the world. But whether it’s your $5 morning latté or a line of coke, you might be surprised to learn why plants bother to build the molecules behind that buzz in the first place. Strangely enough, many plant-based drugs—such as caffeine, cocaine, nicotine and morphine—are all made for the exact same reason: to fight off insects. Why exactly do humans love ingesting insect repellent so much?

Caffeine, Cocaine, Nicotine and Morphine: Pleasurable Pesticides

According to Dr. David Kennedy, who studies plants and the human brain at Northumbria University, to understand what it is about nature’s pesticides that gets us so enjoyably high, it first helps to look at the world from a plant’s perspective. “Unlike animals, plants are rooted in where they live, and can’t really get away from any threats they might need to avoid,” Kennedy says. So to keep hungry herbivores at bay, he explains, many plants can manufacture a slew of defensive chemicals.

Now some plants, like the itchy poison ivy or poison oak, use brute force chemical weapons. But others—such as opium poppies and tobacco plants—take a more delicate approach. These plants still require some animals to get close enough to help them pollinate and breed, so rather than launching a full-scale toxic offensive, they’ll merely mess with a munching bug’s mind.

To do so, these plants produce neurotoxic drugs called alkaloids, which change the balance of chemicals in a bug’s brain. At high enough levels, these drugs can kill insects (and overdose humans) but small amounts will only send them on a bad trip.

Human and Insect Brains

Oddly enough, although these alkaloids evolved to interact with insect brains, “their effects on humans are often strangely similar,” says Kennedy. “For instance, if you give cocaine to bees, it will make them dance more. If you give caffeine or other amphetamines to flies, it will wake them up and make them more aroused. And if you give morphine to insects, it’ll have the same analgesic sort of effect.”

But Kennedy explains this isn’t all that surprising. “Humans have essentially the same brain as an insect. Ours are a little more complicated, but functionally they’re both very similar,” he says. For example, in both brains many of the chemicals that the neurons use to communicate—called neurotransmitters—have the same jobs.

But the mental effect of these drugs does differ in one huge way. “Insects don’t find these drugs addictive or pleasurable, they just find them repulsive,” says Kennedy. This is because human brains have a pleasure-causing reward system which is unlike anything found in the head of a bug—and is based around a neurotransmitter called dopamine. “In humans, by total chance, these drugs just hijack that reward system,” and can flood our brains with dopamine, says Kennedy.

This dopamine rush is what causes the pleasurable effect of these drugs—which can range from a perky disposition (caffeine) to gripping euphoria (cocaine)—and is also what makes these drugs so addictive. But bugs just feel crazed or twitchy, without the pleasure.

Marijuana and Psychedelics

Not all alkaloids or insect repellents in the plant world elicit such a big wave of pleasure in humans. In fact, drugs like cocaine and caffeine are only a tiny subset, and there are plenty of similar drugs out there that will make you little more than sick.

And Kennedy says that when speaking about these addictive drugs, it’s also worth mentioning a few other chemicals that plants produce to interact with the wildlife around them: psychedelic drugs like psilocin (the active ingredient in magic mushrooms) and tetrahydrocannabinol (the active ingredient in marijuana).

Kennedy explains that these psychedelics are distinct from the addictive alkaloids—and this is because of both their chemical structure and the fact that they’re not used solely by plants as pesticides. Rather, these psychedelic drugs can have a large mix of jobs inside the plant, from fighting fungus and microbes to luring in pollinating insects. But just like the alkaloids, their insane effect on the human mind is entirely coincidental, says Kennedy.

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5 Trouble-Shooting Tips to Keep Your House Plant Alive
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Maybe you’ve heard that houseplants can help improve indoor air quality. Perhaps you’ve read that looking at plants can help you focus. Or maybe you just really like how that ficus looks in your living room. But buying a plant and keeping it alive are two different things, and the answer to your botanical woes isn’t always “don't forget to water it.”

Here are five green-thumb tips to make sure your plant stays as leafy green as it was the day you bought it.

1. DON’T OVER-WATER.

You don’t want to neglect your plant, but it’s easy to go overboard with the watering can, and that can be just as harmful as forgetting to water your plant for weeks. A watering schedule can help you keep track of whether or not your plants need attention, but you shouldn’t water just because it’s Sunday and that’s when you usually do it. Before you go to water your plant baby, make sure it actually needs it.

Your plant’s water needs will vary based on the type of plant, its location, how old it is, and plenty of other factors, but there are a few rules of thumb that can put you on the right track. Lift the pot. If it’s heavy, that means that the soil is full of water. If it’s light, it’s dry. Dig a finger into the soil around its roots, making sure to feel beneath the surface. Still damp? Hold off. Dry? Grab the H2O.

If you really struggle to strike the right balance between too much and too little water, consider a smart plant system. And regardless of how often you water, make sure to use a pot with good drainage to prevent root rot.

2. WATCH THE TEMPERATURE.

Be aware of where your plant is situated in the room, and whether there might be any temperature extremes there. Is your fern sitting right above the radiator? Is your peony subject to a cold draft? Is your rosemary plant stuck leaning against a window during a snowstorm?

As a rule, most houseplants can handle temperatures between 58°F and 86°F, according to a bulletin from the University of Georgia. The ideal range is between 70°F and 80°F during the day, and between 65°F and 70°F at night. Below 50°F, sensitive plants can suffer damage to their leaves. However, as with most plant advice, it depends on the species—tropical plants usually do well in higher temperatures, and some other plants are happier in colder rooms.

If your sad-looking plant is sitting in the middle of a cold draft or right next to the heater, consider moving it to a different spot, or at least a few inches away. If it’s near the window, you can also draft-proof the window.

3. MAINTAIN HUMIDITY.

Be mindful of the kind of ecosystem that your plant comes from, and know that keeping it happy means more than just finding the right amount of sun. A tropical plant like an orchid won’t thrive in dry desert air. According to the Biology Department at Kenyon College in Ohio, a dried-out plant will look faded and wilting. You can immerse it in water to help it bounce back quickly. (Warning, though: A plant that’s getting too much moisture can look that way, too.)

If your home gets dry—say, when you have the heater on full blast in the winter or the AC on constantly during the summer—you’ll need to find a way to keep your plant refreshed. Your can buy a humidifier, or create a humidity tray by placing the pot on a tray of pebbles soaked in water. The plant will soak up the humidity as the water under the pebbles evaporates. You can also get a spray bottle and mist your tropical plants periodically with water. (But don't mist your fuzzy-leafed plants.)

Not sure how humid your house is? You can get a humidity gauge (known as a hydrometer) for less than $10 on Amazon.

4. LOOK OUT FOR BUGS.

Even if you do all of the above correctly, you can still struggle to keep a plant healthy due to infestations. Keep an eye out for common pests like spider mites, which will leave brown or yellow spots on leaves or make the plant’s color dull. If you discover these tiny mites (you may need to use a magnifying glass), wash your plant immediately with water to knock off as many mites as possible. Wash the plant with an insecticidal soap, too, but make sure the label says it’s effective for mites.

5. DON’T DISCOUNT THE POT.

Healthy plants often outgrow their homes. if you notice that there are roots coming out the drainage holes at the bottom of your pot, or that water sits on the surface of the soil for a long time before draining down, or that your plant’s roots are coming up out of the soil, it’s time to upgrade to a bigger pot. Signs of a “root bound” plant whose root system is too big for its container can also include wilting, yellowed leaves, and stunted plant growth.

No matter what the size of your plant, it’s good to repot it once in a while, since the nutrients in the soil deplete over time. Repotting creates a fresh nutritional start and can help perk up unhappy plants.

If your plant looks unhealthy and you're still stumped, try consulting the website of a university horticulture department for other signs of plant distress and potential solutions.

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Scientists Find Two New Species of Deadly 'Bird-Catcher' Trees
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Rosimar Rivera Colón

From car windshields to cats, birds around the world face plenty of mortal threats. But as IFLScience reports, avians in Puerto Rico have particularly unique forest foes that until recently were unknown to science. Deep in the island's jungles, researchers have discovered two new species of "bird-catcher" trees, bearing ripe, sticky fruits that—yes—can quite literally trap and kill birds.

As recently described in the journal Phytokeys, the trees—which are members of the genus Pisonia—produce fruits with viscous skins covered in tiny hooks. If a bird perches on the tree, a piece of fruit can stick to its body; when the bird flies off, it takes the fruit with it, potentially dispersing it somewhere else on the island. But if the fruits become too tightly affixed to birds, they can trap and kill their tiny transporters. Their tiny bones sometimes litter the trees' swollen roots, which wrap over rocks and are said to look like elephant feet. 

The trees' discovery has resulted in the long-due recognition of two overlooked female figures in Puerto Rico. The trees were given the names Pisonia horneae and Pisonia roqueae to celebrate the scientific contributions of Frances W. Horne (1873–1967), an American illustrator whose vibrant watercolors depicted hundreds of Puerto Rican plants; and Ana Roqué de Duprey (1853–1933), a Puerto Rican academic, writer, suffragist, and amateur ethnobotanist.

"It only seemed natural to name the two new species after these two extraordinary women who spent decades on large educational projects aimed to divulge botanical knowledge in Puerto Rico," study co-author Jorge C. Trejo-Torres said in a statement. "Just like the two large trees remained unrecognized by science until now, the enormous efforts of these two women, who dedicated part of their lives to botanical work, remained largely unrecognized by the community."

The infructescences of Pisonia roqueae

Jorge C. Trejo-Torres

The 'elephant foot' trunk of Pisonia roqueae

The 'elephant foot' trunk of Pisonia roqueae.

Jorge C. Trejo-Torres

[h/t IFLScience]

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