In ecology news: bats, antbirds, wildfire recriminations, and retractions

by Liza Lester, ESA communications officer Cheatgrass, Bromus tectorum, evolved in the old world, but has been very successful in the new, with a talent for colonizing disturbed rangeland. It fuels early season range fires. Credit, Prof. Dr. Otto Wilhelm Thomé “Flora von Deutschland, Österreich und der Schweiz,” 1885. http://www.biolib.de/ Bats & Birds (& Ants) The Nature Conservancy has built a bat bunker, a cleanable, climate-monitored refuge, near Bellamy Cave in TN. They’re hoping the clean cave can buy time for immunity or science to intervene in the deadly fungus outbreak sweeping through North America, attacking bats in their sleep. Awake, bats resist the infection. But in hibernation, slow metabolism, low body temperature, and the close press of companions make the bats vulnerable. James Gorman “Building a Bat Cave to Battle a Killer” NY Times – 24 Sep 2012 Antbirds trail after army ant swarms, stealing the ants’ hard earned harvest of grasshoppers, beetles, and spiders. Butterflies follow the birds to eat their poop. Natalie Angier talked to ecologist Janeene Touchton in Panama, and cited Touchton’s and James Smith’s 2010 paper in Ecology. Natalie Angier “Feathered Freeloaders at the Ant Parade.”  NY Times 24 Sep 2012 Species loss, delayed numerical responses, and functional compensation in an antbird guild. Janeene M. Touchton and James N. M. Smith. Ecology 2011 92:5, 1126-1136 Tempers ignite over wildfire management Bill Baker of the University of Wyoming says megafires predate fire suppression, logging, and other management interventions blamed for recent conflagrations in North America – contradicting current management practices and a larger body of research. In a podcast, intern Emily Guerin describes (unsympathetically) vitriol from wildfire ecologists toward Baker’s position on fire in the west. Nature told a more canonical story about how “Forests in the American west are under attack from giant fires, climate change and insect outbreaks. Some ecosystems will never be the same.” Emily Guerin “Fire scientists fight over what Western forests should look like.” High Country News 17 Sep 2012. Cally Carswell, Emily Guerin, Neil LaRubbio “West of 100: Fire & Brimstone.” (audio) High Country News 25 Sep 2012. Mark A. Williams and William L. Baker Testing the accuracy of new methods for reconstructing historical structure of forest landscapes using GLO survey data. Ecological Monographs 2011 81:1, 63-88 Michelle Niihuis “Forest fires: Burn out.” Nature News 19 Sep 2012 Ira Flatow, on location at Boise State University, was also talking about wildfire last week. “Nearly a million acres are burning in the West right now.” Range fires. Who’s to blame? Is this a new thing? Today, we’re blaming Cheatgrass. Flatow talks to Jen Pierce, a paleo fire ecologist, and Mike Pellant,...

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Fungus makes zombie ants administer ‘death bite’ at noon

Researcher David Hughes has expanded research on a parasitic fungus and its carpenter ant host. As explained in an excerpt from a previous EcoTone post: Scientists have found that the parasitic fungus Ophiocordyceps unilateralis has possibly been invading carpenter ants (Camponotus) for 48 million years. The parasite not only infects the ant, but it manipulates the ant’s behavior, driving it to bite the underside of the leaf at the veins. Once the ant hits an optimal location, the fungus grows rapidly, killing the ant and preparing it to release a new spore. During this process, the ants leave distinct marks, also known as “death bites,” on the leaves as they bite the veins in search of a prime spot for fungal growth. It is this unique pattern that led researcher David Hughes to a 48 million year old leaf with similar markings. According to a Nature News article, Hughes contacted Conrad Labandeira, a palaeoecologist at the Smithsonian’s National Museum of Natural History, who, as it turns out, had noticed a leaf with similar markings. As Hughes said in the article, “It is not normal ant behavior to bite into the leaf vein because it has no real nutritional value to the ant and can in fact be toxic in some plant species.” This finding, as he explained in a Biology Letters study published [last year], indicated that the carpenter ants were infected with the parasitic fungus when the ant made the leaf marks. As reported in Discover Magazine’s blog 80beats, “If Hughes’ dating is correct, then the fungi have had plenty of time to fine-tune their zombifying practice into the ruthlessly efficient mind control we see today.” These findings were recently backed up in a study published by Hughes, now a researcher at Pennsylvania State University, and colleagues in the journal BMC Ecology this week. They found that the ants bit on the leaf veins around noon—a time that appeared to be specific for the fungus. As Hughes said in a Live Science article, “Synchronized arrival of zombie ants at the graveyards is a remarkable phenomenon. It adds a layer of complexity on what is already an impressive feat. However, although ants bite at noon they don’t in fact die until sunset. Likely this strategy ensures (the fungus) has a long cool night ahead of it during which time it can literally burst out of the ant’s head to begin the growth of the spore-releasing stalk.” The ants—in the case of the most recent study, Camponotus leonardi—live in the canopy of trees but come to the forest floor occasionally. It is here that they contract the fungus. It is...

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Buffo the truffle-hunting dog, night-blooming balsa trees and fire-ant-made rafts

Truffle shuffle: According to a letter published in the April issue of Frontiers in Ecology and the Environment, Buffo the truffle-hunting dog made an unusual find: a one-pound Burgundy truffle in the forests of southern Germany in November. As lead author Ulf Büntgen said in a recent Wired Science article, “This wasn’t a small find, but a big and expensive truffle with lots of smaller ones around. It was strange to find it in an area where, so far, this truffle’s existence has never been reported…The season, early November, was also unusual. This led us to ask, ‘what is driving truffle growth here? Is it connected to climate?’” Read more at “Truffle-Hunting Dog Finds Jackpot in Unexpected Place.” Blooming balsa: Large, blooming balsa trees attract wildlife in the night with their nectar-laden blossoms. Natalie Angier elaborated in a National Geographic article: “When [the capuchin monkeys] look up again, their muzzles are speckled with pollen, which from the [balsa] tree’s perspective is the whole point of its flowers: to capture the attention of a pollinator long enough that the animal can’t help but be brushed with the plant’s equivalent of semen, which, if all goes well, the inadvertent matchmaker will eventually deliver to the female parts of another balsa tree’s flowers. The exchange is simple: You get drinks on the house, my gametes get a ride on your face.” Read more at “Panama’s Ochroma Trees.” Deepwater update: One year after the Deepwater Horizon explosion sent oil leaking into the Gulf of Mexico, scientists are still researching the longterm ecological impact of an incident that is unique in many ways. That is, “[t]he field of coral was just 11 kilometres from the Deepwater Horizon well head, which earlier in the year had spewed out more than 4 million barrels of oil and a similar amount of methane—the largest ever accidental release in the ocean,” wrote Mark Schrope in a Nature article. “The spill was unique in other ways, too. Located beyond the continental shelf and some 1,400 metres below the surface, it happened in deeper water than any other major spill in history.” Read more at “Oil spill: Deep wounds.” Peacock spots: Mate selection in peacocks may be more complex than previously thought. That is, the number of eyespots on a male peacock’s feathers is likely not the only factor responsible for female’s mate selection.“The threshold idea certainly makes sense at first glance, says Adeline Loyau, a peacock researcher at the CNRS research station in Moulis, France,” in a Science News article by Susan Milius. “The struggle to understand the long-familiar peacock, adds [Loyau], ‘suggests that we are still far from...

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The tiny, diligent gardeners of the Amazon

The gardeners described here are not concerned with trimmed topiaries or manicured lawns—though, like designers of landscape gardens, these workers are exceptionally picky. And they have to be if they are going to survive. That is, ants such as Myrmelachista schumanni and Camponotus femoratus of South America depend on certain plants for shelter, and in return, they offer these plants nutrients and protection from predators. As a result, they have developed a mutualistic relationship that has led to an incredible resilience for both species. For example, the ant M. schumanni has kept the plant Duroia hirsute alive in one area of the Amazon, known as a devil’s garden to locals, for more than 800 years. This particular type of ant-plant dependency is plentiful in the Amazon and it creates eerie patches of monoculture gardens amidst the rest of the lush, diverse rainforest. As biologist and photographer Alex Wild described in a recent Myrmecos blog post (complete with photos): I had been following an army ant raid for half an hour through dense tropical forest when the trees unexpectedly parted to reveal a small clearing. Sun broke through the canopy and fell on a low tangle of furry plants. It was a monoculture, looking as though planted by a reclusive sort of gardener. I had stumbled into a Devil’s Garden. Local lore holds that malevolent forest spirits create these unnatural crop circles, but the truth is just as weird. Devil’s Gardens are [cultivated] by ants. The plant species that compose these gardens—mostly in the genera Tococa, Clidemia, and Duroia—sport swollen structures filled by the nests of tiny Myrmelachista ants no more than 3 millimeters long. The ants are meticulous about caring for their hosts, removing [pesky] herbivores and injecting formic acid into the saplings of competing plants. Another ant species, C. femoratus, gathers the seeds of particular plants to cultivate in its nests, called ant gardens, and made of a mixture of animal feces, digested plants and other organic material. These nests are attached to vines, the sides of trees and even high up in the tree canopy. As Elsa Youngsteadt explained in the podcast Curiouser and Curiouser, ants followed chemical signals given off by seeds of certain plants, collected the seeds, carried them back and embedded them in the walls of the nests. The plants benefitted from the fertilizer mixed in the nest, and in turn, the roots helped to add structure to the ant garden. In addition, the leaves protected it from heavy rains that would otherwise have caused the material to disintegrate. “There are about ten plant species that are in ant gardens regularly that you don’t...

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Army ants, beard microbes and ant-mimicking jumping spiders

Army ant week: Biologist and photographer Alex Wild reported on army ants all last week  in a series of posts on his blog Myrmecos. In one post, he described how army ants link with one another using hooks on their feet: “When the time comes to encamp, they can string together living curtains of ants in a matter of minutes. Army ant bivouacs are made from the ants themselves, a vibrant structure that protects the vulnerable brood and maintains temperature within a single degree of optimal.” Read more or view photos at “Army Ants as Living Legos.” Funky pheromones: Chemical signals, as ecologist and blogger Tracey Switek put it in a recent post on The Olive Tree, “don’t have to just be scents that waft through the air…They can be toxins, which send a very clear signal either because they make the plant taste bad or outright kill or injure anything that tries to eat. We’re all familiar with the culinary herbs such as basil, mint, thyme, cilantro and sage… But the real purpose of those pungent chemicals is to discourage insect predation.” Chemical signals can change the behavior of a species in many ways—for example, pheromones on squid eggs can cause males to become aggressive at the slightest touch (see above video). Read more at “Everybody Stinks: Chemical Signaling in the Undergrowth” and at “Rage-inducing chemical on squid eggs turns males into violent thugs” by Not Exactly Rocket Science. Woody vines: Stefan Schnitzer from the University of Wisconsin in Milwaukee and colleagues gathered data on the abundance of woody vine growth in American tropical and subtropical forests, and the cascading effects they had on biodiversity and water supply. According to a recent Live Science article, “It’s possible an increase in woody vines could change the nutrient dynamics of forests, in part because of differences between their leaves and the leaves of tropical trees, all of which ultimately fertilize the forest floor.” Read more at “Twisted Tropics: Growth of Vines Imperils Ecosystem.” Ant-mimicking spider: Michael Bok described the jumping spider, Myrmarachne plataleoides, in his blog Anthropoda. At first glance, the spider appears to be a red ant, but upon further examination, the  four pairs of legs become noticeable (see above video). “It makes up for a lack of antennae, and an overabundance of legs, by holding its forelegs up, alongside the head,” he wrote. “Its huge anterior medial eyes are colored to match the head when not viewed directly, and the posterior lateral eyes are enlarged, with darkened pigment around them to mimic an ant’s eyes. Also, the cephalothorax and abdomen are deformed and narrowed considerably.” Read more at...

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Ecology in videos and podcasts

Oysters proposed for cleaning up New York’s rivers, mall music has a bigger impact than boosting sales, cephalopods advance research in neuroscience and robotics, how gut bacteria might be shaping brain development and behavior and E.O. Wilson discusses a life of research on ants. Here are the remaining links from January. Oyster-tecture: The U.S. Environmental Protection Agency released a study today showing heavy contamination in the Gowanus Canal in New York City. In the above TED video, landscape architect Kate Orff discusses plans to reestablish oysters to the Canal as a way to filter pollution and create habitats for other species. “One oyster can filter up to 50 gallons of water a day,” said Orff, “…and they become the bedrock of any harbor ecosystem.” Read more at “Reviving New York’s rivers — with oysters!” Lowering music emissions: Stanford University journalism students put a new spin on the term noise pollution: They calculated just how much energy is used to play background music in malls in the U.S. As explained in the Scientific American podcast 60-Second Earth, “[the students] crunched the numbers on how much energy it takes to play all that pop and came up with a figure of 1.18 gigawatt-hours. Given the present energy mix that means Mantovani adds more than 3,000 metric tons of CO2 to the atmosphere each year.” Read more and listen at “Another Reason to Hate Shopping Sound Tracks.” Cephalopod brains: In a lengthy BoingBoing video, science journalist Maggie Koerth-Baker explains the cephalopod—such as octopuses and squid—brain and how it is used for communication, object detection and predator avoidance. “The secret to the octopus’ success: its brain,” she said in the video. “This incredibly weird structure, from our biased vertebrate mammalian perspective…is the result of an evolutionary process hundreds of millions of years removed from our own, creating an organ that looks on the surface nothing like what we’ve come to expect an honest brain to be.” Koerth-Baker applies these brain functionalities to neuroscience and robotics. Read more at “everybody loves cephalopods.” E.O. Wilson on ants and life: In an Encyclopedia of Life podcast, E.O. Wilson, now 81, discusses his lifelong study of ants—including the red imported fire ant that he discovered at the age of 13 in Alabama—and what drives him to continue his research. “I think my life proves, if you are truly a dedicated naturalist, if you’ve known the joys of exploring  biodiversity, and you’ve become fairly familiar with ecosystems that feel like home to you when you step into them…that it is a source of lifelong pleasure, adventure, challenge and excitement,” he said in the podcast.  Read more and listen...

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An ant’s eye view of sand

To an ant, a piece of garnet or a shark’s tooth is merely another boulder to excavate for the expansion of the nest. And for humans, these bits of treasure would largely go unnoticed as just another grain in an anthill. But, as the blog Neatorama pointed out this week, every inch of sand is a world of discovery to photographers and sand collectors. Specifically, Flickr user Mouser Williams captures the history and biological connections of each location through his macro lens. For example, the pointy star sand from beaches in southern Japan—such as on Iriomote Island in Okinawa—was formed from the death of Foraminifera. In this case, these organisms are marine protists with calcium-based skeletons that wash ashore to create the “sand.” Williams also described how the hard work of ants creates unique sand compositions: “…Ant sand from a site near Taos, New Mexico…has a remarkably high concentration of garnets. The reddish faceted spheres are garnets hauled up to the surface by the ants. Because they are roughly spherical, they tend to roll down the slopes of the ant hills and collect in an annulus around the base of the ant hill.” Using a magnet, Williams extracted some of the garnets and photographed them separately. “These garnets range in size from 1mm to 5mm in diameter,” he explained. “There are presumably larger garnets in the soil in this area, but with ant sand you are limited to things ants can lift and carry.” In another photo, ants excavated fossil bits from their nest in the Morrison Formation of New Mexico, a location that at one point supported dinosaurs, reptiles, termites, conifers, ginkgos, tree ferns and more along the area’s rivers. The site also had a diverse group of sauropod species at one time. Photo Credit for Star Sand Naked Eye (sand on a finger): Geomr Photo Credit for all other sand photos: Mouser...

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From the Community: fish-mimicking octopuses, aquanauts and the evolution of ecology

An octopus that mimics toxic sea creatures, the tobacco plant sends out an SOS when attacked, the genetic differences between ant social castes, unusually high records of jellyfish swarms this summer and Simon Levin discusses the evolution of ecology and where it is headed next. Here are stories in ecology wrapping up the month of August.

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