It always helps to have good timing. And no one seems to understand that better than the tobacco plant Nicotiana attenuata, which grows in Western United States and flowers at night [The New York Times]. Normally, the tobacco plant is pollinated by hawkmoths that visits its flowers every night. But when these hawkmoths leave eggs behind that develop into leaf-chomping caterpillars, the plant’s self-defense snaps into place and switches to flowering in the day. That attracts a different pollinator, the hummingbird.
Ecologist Danny Kessler noticed this change when he was trying to get a picture of the plant being pollinated for a study. He saw that the plant was not just flowering in the day but also that they had changed their flowers to make them more attractive to hummingbirds: they emitted less of a chemical that attracts moths; they had less sugar in the nectar, which is the way hummingbirds prefer it; and they were more tube-shaped, making them friendly to a hummingbird’s long, thin beak [ScienceNOW Daily News].
Part animal, part plant, bright green, and totally bizarre: Meet the sea slug Elysia chlorotica.
Biologists already knew that this organism, native to the marshes of New England and Canada, was a thief that somehow pickpocketed genes from the algae it eats. At last week’s meeting of the Society for Integrative and Comparative Biology in Seattle, researcher Sidney Pierce said he has found that the slugs aren’t just kleptomaniacs—they use the pilfered genes not only to make chlorophyll, but also to execute photosynthesis and live like a plant. Said Pierce: “They can make their energy-containing molecules without having to eat anything,” Pierce said. “This is the first time that multicellular animals have been able to produce chlorophyll” [LiveScience].
Watch out next time you’re in your garden—carnivorous plants are lurking where you least expect. OK, they aren’t really dangerous, unless you’re a small insect, but now that we have your attention, scientists are reporting that common plants like petunias, potatoes, and tomatoes may actually have a carnivorous nature.
Botanist Mark Chase argues that carnivorous plants are much more widespread than previously thought, they just act in more subtle ways than the Venus flytraps and pitcher plants of the world. For instance, the cross-leaved heath (Erica tetralix) is not typically considered a carnivorous plant, but this pink flower possesses sticky, adhesive glands and dwells in poor soils. Also, while carnivorous seeds might be a strange concept, those of the shepherd’s purse (Capsella bursa-pastoris) possesses a sticky layer with chemicals that can attract, kill and digest victims [Fox News]. Chase and his colleagues argue that about 300 more plants could be fairly classified as carnivores, in addition to the roughly 650 known carnivorous plants. Of the new suspects, tobacco and tomato plants are among the most famous.
From an ancient Peruvian civilization comes this warning: Don’t chop down all your trees, or there will be hell to pay.
The Nazca people are famous for the enormous earthworks they carved into an arid plateau, in designs that range from simple geometrical forms to representations of animals like hummingbirds, lizards, and monkeys. They were previously known to have disappeared around A.D. 500, when massive floods powered by El Niño ravaged the valley where they made their home. Now, a new study that examined the pollen in buried layers of soil in order to trace the horticultural history of the land may have revealed why those floods were so devastating.
The Ica Valley, about 120 miles south of Lima, is barren today but was once a riverine oasis — a fertile landscape capable of supporting many people. The key to that fertility was a tree called the huarango [Los Angeles Times]. The huarango tree provided wood for building and fuel, and seed pods that can be ground up and used in flour or beer. Its branches caught the water in morning mists, and its roots stabilized the topsoil. Says lead researcher David Beresford-Jones: “These were very special forests…. It is the ecological keystone species in the desert zone enhancing soil fertility and moisture and underpinning the floodplain with one of the deepest root systems of any tree known” [BBC News].
Scientists have used nanotechnology in some bizarre applications—nanotube speakers and glue are just two examples. Now carbon nanotubes may have a use as fertilizer, according to a new study. Plant biologist Mariya Khodakovskaya and nanotechnologist Alexandru Biris … planted tomato seeds in a growth medium that contained carbon nanotubes. They found that the seeds germinated sooner and seedlings grew faster than those in a non-treated medium [New Scientist]. After 12 days, 72 percent of the treated seeds had germinated compared with 30 percent of the untreated group. After four weeks, the nanotube-supplemented seeds were twice as tall and had twice the biomass. However, the root systems in both groups were roughly the same.
Similar findings have been reported previously, but until now nobody understood how nanotubes sped and enhanced plant growth. The new study, which recently appeared in the journal ACS Nano, proposes that nanotubes poke holes in the seeds, which allows water to seep in and speeds up germination. However, some researchers are skeptical that a complex process like germination can be enhanced simply by poking holes in the seed’s coating, and at least one researcher is suggesting that the nanotubes cause a hormonal imbalance in the plants.
Before nanotubes could become a commercial fertilizer, their effect on the environment would have to be studied, with close attention to how nanotubes move through the food chain. Some single-walled nanotubes are toxic to some insects; testing on mice has found multi-layer nanotubes (like the kind used in the study) have carcinogenic effects similar to those of asbestos [Popular Science].
The discovery of a pair of genes that prompt rice plants to grow extra-tall when submerged in water could potentially lead to new hardier varieties of rice that yield food even in flooded conditions, and could help out farmers in flood-prone nations like Thailand and Cambodia, according to a study published in Nature.
Researchers discovered a pair of genes known as SNORKEL, which spurs growth among the plants when they are completely submerged, allowing the plants to survive by keeping their leaf tops above the water. As water levels rise, accumulation of the plant hormone ethylene activates the SNORKEL genes, making stem growth more rapid. When the researchers introduced the genes into rice that does not normally survive in deep water, they were able to rescue the plants from drowning [AP].
Scientists have created genetically engineered corn plants that resist a root-destroying larvae by emitting a chemical call for help, summoning a parasite that preys on the larvae.
The larvae of the western corn rootworm (actually a beetle) is considered the most destructive corn pest in the United States and plagues parts of Europe as well. Known as the billion-dollar bug, the rootworm is said to be responsible for crop damage and pest-control spending valued at more than nine figures [National Geographic News]. To fight the larvae without the use of synthetic pesticides, researchers created corn plants that release a chemical compound into the soil, which calls forth parasitic nematodes to come and infest the beetle larvae.
The fungus that caused the notorious Irish potato famine of the 1840s and 1850s is spreading among tomato and potato plants in the northeastern United States. Known as late blight, the fungus spreads easily among plants by airborne spores. This year’s epidemic has taken root at major garden retailers, eventually invading not only home gardens but also major commercial and organic farms.
The disease causes dark lesions on the plant’s leaves and stems; tomatoes then turn brown and decay, emitting a rotten odor. Although the fungus is not dangerous to people, its effects render infected plants inedible. “Late blight has never occurred this early and this widespread in the United States,” said Meg McGrath, a plant pathologist [Reuters]. Its spread has been facilitated by the cool, wet weather the Northeast has experienced this summer, along with an increased number of home gardeners looking to grow their own food as a result of the recession. This year’s blight also is particularly dangerous because of how early it appeared in the growing season; usually, the blight hits plants late, after most of the fruit has been harvested [The Baltimore Sun].
Human beings are increasingly making their homes on the coasts of continents, but this demographic shift is taking a toll on a sensitive coastal ecosystem that is often overlooked: seagrass meadows. A new analysis of seagrass abundance around the world found that 27 percent of these meadows have disappeared since 1879, and the rate of loss is accelerating. The study’s authors write: “Seagrass loss rates are comparable to those reported for mangroves, coral reefs and tropical rainforests, and place seagrass meadows among the most threatened ecosystems on earth….. Our report of mounting seagrass losses reveals a major global environmental crisis in coastal ecosystems, for which seagrasses are sentinels of change” [Nature News].
Endangered species expert Susanne Livingstone notes that despite these losses seagrass rarely makes it into the public consciousness. “It’s probably because they’re not as sexy [as corals], they’re not as attractive,” she says. “They’re just as ecologically important if not more so” [Nature News]. Seagrass meadows provide grazing for a variety of marine animals, including the green turtle and the manatee-like dugong. The coastal areas also serve as nurseries for fish; both coral reefs and commercial fisheries would feel the impact if seagrass meadows vanish.
The seeds that twirl down from maple trees every spring can fly as far as a mile, with each wing-shaped seed spinning like a whirligig on the air. Studies have shown that the seed’s whirling, called auto-rotation, gives it extra lift, but why this occurs has never been explained. It took an aerospace engineer, David Lentink of the Wagenigen University in the Netherlands, to figure it out [The New York Times].
Lentink and his colleagues first studied how a model of a maple seed moved in a tank of oil, and then filmed a real seed falling through a smoke-filled wind tunnel, which allowed them to observe the air currents around the seed. The images the team obtained showed that a swirling maple seed generates a tornado-like vortex that sits atop the front leading edge as the “helicopter” spins slowly to the ground. This leading edge vortex lowers the air pressure over the upper surface of the maple seed, effectively sucking the wing upward to oppose gravity [Live Science].
The oil-rich and weedy plant jatropha has been hailed as the most promising source of biofuel on the planet, and one airline has already begun testing a jatropha-derived fuel in its jumbo jets. But a new analysis suggests that the plant may not be a miracle crop destined to solve all our energy problems: Current jatropha plantations are not realising the oil yields that drove the “Jatropha euphoria” [EcoWorldly].
It was previously thought that the hardy jatropha plant would require less water than other biofuel crops like sugarcane and corn and could grow in marginal soil, so growers wouldn’t have to take fertile land out of agricultural use. But the new study rebuts that assumption. “The claim that jatropha doesn’t compete for water and land with food crops is complete nonsense,” says study coauthor Arjen Hoekstra. The researcher says it’s true that the plant can grow with little water and can survive through periods of drought, but to flourish, it needs good growing conditions just like any other plant. “If there isn’t sufficient water, you get a low amount of oil production,” Hoekstra says [Technology Review].
The Greek poet Homer was first to make written reference to a “sardonic smile,” and in the millennia since the phrase has been used to denote a bitter or cynical grin. Now, researchers in Italy say they’ve discovered a poisonous herb that gave rise to Homer’s coinage: a plant called hemlock water-dropwort that grows wild across the island of Sardinia and was used in the ancient Sardinians’ death rituals. The plant was used in pre-Roman times for the ritual killing of old people who had become a burden to society. “According to ancient historians, elderly people unable to support themselves were intoxicated with the herb and then killed by being dropped from a high rock or by being beaten to death,” the research team wrote [Telegraph]. The plant’s toxins can cause facial muscles to contract, researchers note, leaving an eerie smile frozen on the face of the corpse.
The poet Homer first used the word ‘sardonic’ as an adverb when describing Odysseus’ smile. The Greek hero “smiled sardonically” as he dodged an ox jaw thrown by one of his wife’s former suitors. According to some scholars, Homer coined the word after learning that the Punic people who settled Sardinia gave condemned people the smile-inducing potion [Discovery News].
Using a fancy piece of chemistry equipment to study the chemical composition of wine, European researchers have one-upped the sophisticated palates of wine connoisseurs. The researchers used ultra high resolution mass spectrometry to sort through all the chemical compounds present in wines that had been aged in oak barrels, and found that for each wine, they could determine which French forest the oak was cut from. No other approach – analytical or sensory – has been able to significantly discriminate wines according to the species or the origin of the oak used for the barrels before, they say [Chemistry World].
The findings could prove useful to wine connoisseurs and historians, the researchers said, concluding that their findings produced “chemical representations of the way such noble nectar can shape, on the (tongue) of the wine taster, some of the outlines of the scene of its birth” [AP]. Similar analyses could also be used to detect wine fraud, the researchers noted.
Twenty-three years ago, Chernobyl’s nuclear reactor #4 exploded in the world’s worst nuclear accident to date. Radioactive material was scattered across the surrounding countryside, and the authorities evacuated the nearby town of Pripyat, which remains a ghost town to this day. However, nature has not evacuated the scene, and all manner of plants and animals continue to inhabit the area. “There are no dogs with two heads,” says Martin Hajduch of the Slovak Academy of Sciences – although birds, insects and humans have all been affected to a greater or lesser extent by radioactive fallout [New Scientist].
Hajduch and his colleagues wanted to study how plants had adapted to the radioactive soil, so they grew a plot of soybeans just three miles from the remains of the nuclear power plant, well within the restricted zone that extends 19 miles from the reactors. They grew another patch of soybeans 60 miles from the power plant in uncontaminated soil, and analyzed the resulting beans. Their findings not only illuminate the hardiness of life, they also suggest ways to genetically engineer plants to make them resistant to radiation.
80beats is DISCOVER's news aggregator, weaving together the choicest tidbits from the best articles on the day's most compelling topics.
80beats is written by Veronique Greenwood and Valerie Ross. This team darts through each day's science news faster than the ruby-throated hummingbird that beats its wings 80 times per second. Send ideas, tips, suggestions, and complaints to [azeeberg at discovermagazine dot com].
It always helps to have good timing. And no one seems to understand that better than the tobacco plant Nicotiana attenuata, which grows in Western United States and flowers at night [The New York Times]. Normally, the tobacco plant is pollinated by hawkmoths that visits its flowers every night. But when these hawkmoths leave eggs behind that develop into leaf-chomping caterpillars, the plant’s self-defense snaps into place and switches to flowering in the day. That attracts a different pollinator, the hummingbird.
Part animal, part plant, bright green, and totally bizarre: Meet the sea slug Elysia chlorotica.
Watch out next time you’re in your garden—carnivorous 
From an ancient Peruvian civilization comes this warning: Don’t chop down all your trees, or there will be hell to pay.
Scientists have used nanotechnology in some bizarre applications
Scientists have created 
The fungus that caused the notorious Irish potato famine of the 1840s and 1850s is spreading among tomato and potato plants in the northeastern United States. Known as late blight, the fungus spreads easily among plants by airborne spores. This year’s epidemic has taken root at major garden retailers, eventually invading not only home gardens but also major commercial and organic 
Human beings are increasingly making their homes on the coasts of continents, but this demographic shift is taking a toll on a sensitive coastal 
The seeds that twirl down from maple 
The oil-rich and weedy plant jatropha has been hailed as the most promising source of 
The Greek 
Using a fancy piece of chemistry equipment to study the chemical composition of 
Twenty-three years ago, Chernobyl’s nuclear reactor #4 exploded in the world’s worst nuclear accident to date. Radioactive material was scattered across the surrounding countryside, and the authorities evacuated the nearby town of Pripyat, which remains a ghost town to this day. However, nature has not evacuated the scene, and all manner of plants and animals continue to inhabit the area. “There are no dogs with two heads,” says Martin Hajduch of the Slovak Academy of Sciences – although birds, insects and humans have all been affected to a greater or lesser extent by radioactive fallout [
