Sugar Substitute Turns Out to Be Potent Insecticide
James O'Hanlon, Macquarie University
Animals and insects that resemble flowers deceive in a unique and powerful way, since who could resist a beautiful flower?
In this case, the "orchid" is actually a predatory insect -- the orchid mantis. Researcher James O'Hanlon of Macquarie University and colleagues recently studied the unusual insects in Malaysia.
"Their bright floral colors and petal-shaped legs create a tantalizing lure for insects," O'Hanlon told Discovery News, adding that they attract flying insect pollinators more than actual flowers in the region do. "So it seems that orchid mantises not only look like flowers, but they may also even beat flowers at their own game as they deceptively attract their unsuspecting prey."
The star-nosed mole is in the record books for a few different reasons. First, it is the world's fastest eating mammal. Second, its nose looks like a coral-colored flower, allowing the mole to poke out of the ground as though it were a plant.
Finally, the flower or "star" on its nose has the highest density of nerve endings known in any mammalian skin, according to biologist Diana Bautista of the University of California at Berkeley and colleagues. By studying the nose, they are hoping to identify genes that may mediate touch and pain, leading to better treatments for chronic pain conditions.
Fred Hsu, Wikimedia Commons
Flower hat jellyfish, native to the West Pacific off the coast of southern Japan, sport translucent, pinstriped bells that make up this marine animal's "flower."
The tentacles below can sting, and are used to catch small fish. Humans who have the misfortune of encountering the flower hat jellyfish can also be stung, and often suffer a nasty rash as a result.
Raimond Spekking, Wikimedia Commons
The term anthozoa comes from the Greek words for flower and animals. These flower animals are so-called because their earliest stage of growth takes on a floral appearance.
Relatives of anthozoa were in existence possibly as early as 570 million years ago, putting those ancestors well ahead of the dinosaurs. They are among the oldest known types of animals on Earth.
Yuvalif, Wikimedia Commons
The devil's flower mantis has three distinct looks. It can, as this image shows, appear as its true insect self. Here, one was snapped marching on a car tire. But among plants, the other two looks become more evident.
Imagine this mantis sitting on a green leaf. It would seem to be an extension of that leaf, or just blend in with the green. When the insect lifts its forelegs, however, bright colors are revealed. In this pose, it resembles an orchid. To other devil's flower mantises, the pose signals a threat, making the aggressor look large and mean.
The High Fin Sperm Whale, Wikimedia Commons
"Lionfish" refers to an entire genus of venomous marine fish. They sometimes resemble floating tropical flowers, but the appendages are actually spiky and full of venom.
Flowers display colors, in part, to attract pollinators. Color for lionfish is meant to do just the opposite: repel others. Like a bright red stop sign, the color is meant to gain attention. The different colors tell would-be predators that the lionfish can be dangerous.
Darius Bau, Wikimedia Commons
When wrapped around a twig, the pale tussock caterpillar could easily be mistaken for an unusual bright yellow-hued flower. The coloration, as for the lionfish, warns others not to eat it.
The caterpillar's color and appearance also functions as a flower disguise. Once the caterpillar turns into a moth, all of that psychedelic color fades away, leaving behind beige and brown tones.
BerndH, Wikimedia Commons
Animals and insects aren't the only ones that fool others with their looks. Flowers also sometimes take on the appearance of animals.
The bird of paradise is a classic example. But nature seems to be teasing us with the monkey orchid. From a distance, this flower looks just like a lavender and white orchid. Up close, however, the flower resembles a monkey, complete with a head, long arms and a tail.
Orchi, Wikimedia Commons
With Halloween around the corner, special mention goes to the orchid Dracula gigas. While it may not look like Dracula, it does take on human-like features.
From above, as seen in this photo, it appears to have eyes, a nose, a mouth and quite a dramatic hairdo.
Researchers have just discovered that erythritol, the main component of the popular sweetener Truvia®, kills insects.
The study, published in the latest PLoS ONE, suggests that the popular sugar substitute could be an effective and human-safe insecticide. No other known sweeteners currently on the market exhibit these toxic effects on insects, according to the authors.
Scientists are always on the lookout for potent bug killers that won't harm people, so it was surprising that the common sweetener does the deadly job so well.
"I feel like this is the simplest, most straightforward work I've ever done, but it's potentially the most important thing I've ever worked on," senior author Sean O'Donnell, a Drexel University professor of biology and biodiversity, was quoted as saying in a press release.
Another researcher who worked on the project was ninth grader Simon D. Kaschock-Marenda. Three years ago, he questioned why both of his parents had stopped eating white sugar when trying to eat healthier.
"He asked if he could test the effects of different sugars and sugar substitutes on fly health and longevity for his science fair, and I said, 'Sure!'" recalled Daniel Marenda, Simon's father who is also a co-author of the study.
The father and son duo went to a local supermarket and bought every type of sugar and sugar substitute that they could. They raised "baby" flies (supplied by Marenda's lab) on the various compounds to see what would happen.
"After six days of testing these flies in our house, he (Simon) came back to me and said, 'Dad, all the flies in the Truvia® vials are dead,'" Marenda said. "To which I responded, ‘OK…we must have screwed up somehow. Let’s repeat the experiment!'"
They did, and determined that flies raised on food containing Truvia® lived for only 5.8 days on average, compared to 38.6 to 50.6 days for flies raised on control and experimental foods without Truvia®. Flies raised on food containing Truvia® also showed noticeable motor impairments prior to their deaths.
"Indeed what we found is that the main component of Truvia®, the sugar erythritol, appears to have pretty potent insecticidal activity in our flies," Marenda said.
Erythritol is a naturally occurring sugar alcohol that is present in small amounts in many fruits. It has been tested in humans at high doses and these studies have concluded that it's safe for humans to consume. As a result, it has been designated as a generally recognized safe food additive by the U.S. Food and Drug Administration since 2001 and is also approved as a food additive in many other countries.
The scientists determined that stevia plant extract, which is also in Truvia®, had no ill effect on the flies. Only erythritol really did a number on them.
"We are not going to see the planet sprayed with erythritol and the chances for widespread crop application are slim," O'Donnell said. "But on a small scale, in places where insects will come to a bait, consume it and die, this could be huge."
The researchers next hope to find out if the sweetener kills other insect pests, such as termites, cockroaches, bed bugs and ants.
Photo: Flies that died after consuming food that contained the sweetener erythritol. Credit: Baudier et al., Drexel University