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Sparganium Erectum
I should first of all note that I've changed the name of the plant posted by marcella2 from Sparganium ramosum to the catch-all Sparganium erectum (many Sparganium are listed as being synonymous to Sparganium erectum). I'm following the nomenclature suggested by Missouri Botanical Garden's TROPICOS database, but with reservation. In a conversation with Richard Lansdown ten days ago or so, Richard expressed the opinion that a number of of the less-examined plants sharing the same name in both Europe and North America are actually quite different from one another. Even the Flora of North America expresses reservation about the nomenclature within this genus, because the last work done on it (in the mid 1980s) did not contain detailed studies of the species across their complete ranges. A grain of salt is required, it seems. I've an inexplicable soft spot for plants in the genus Sparganium, despite the fact that some have been declared a noxious weed. It may be that the soft spot stems from the exotic appearance - exotic, at least, to someone first learning plants through observing the native plants of Manitoba. I still find them interesting, and I know if I encountered some similar to these, I'd spent quite a bit of time photographing them......... Posted by: Erica Permalink Source Who said nature is not sexy?
Who said nature is not sexy? Nature watch by a naturalist......... Posted by: Erica Permalink Source Eating Habits Of Rain Forest Insects
"This is a big step forward in the quest to understand why there is so much biodiversity in the tropics," said Weiblen, principal investigator and senior author for the National Science Foundation-funded research. The study is reported in the Aug. 25 issue of the journal Science. The research showed that insect species in tropical and temperate forests dine on about the same number of tree species, despite the more diverse menu in the tropics. "The tropical forest cafeteria offers a number of more options than the temperate forest," Weiblen said. "Our study confirms that the choices tropical insects make are quite similar to those of insects in less diverse forests of places like Minnesota". The study rejected an alternative theory that tropical insects are actually picky eaters who prefer fewer host plants than their temperate counterparts. "Theory predicts that similar species coexist by dividing up resources like food and space," Weiblen said. "The unparalleled diversity of plant-eating insects in the tropics could be explained as per this theory if tropical insects were more choosy than those in temperate forests. But it hasn't been possible to compare what's on the menu until now"......... Posted by: Erica Permalink Source Even microbes favor their own kin
Dictyostelium purpureum cells, labelled with a green fluorescent dye, streaming to form a multicellular fruiting body
Credit: Natasha Mehdiabadi/Rice University The study provides further proof of the surprisingly sophisticated social behavior of microbes, which have been shown to exhibit levels of cooperation more typically linked to animals. "By recognizing kin, a social microbe can direct altruistic behavior towards its relatives," said postdoctoral researcher Natasha Mehdiabadi, the lead author of the study. Recognizing one's own family is a common trait among animals be they chimpanzees, ground squirrels or paper wasps and because kin recognition can strongly influence cooperative behaviors it can also significantly impact the social evolution of species. While researchers have repeatedly documented cases of kin recognition, the Rice study is among the first to document the more sophisticated trait of kin discrimination in a social microorganism. The new study is based on an examination of single-celled Dictyostelium purpureum, a common soil microbe that feeds on bacteria. In the wild, when food runs short, D. purpureum aggregate together by the thousands, forming first into long narrow slugs and then into hair-like fruiting bodies. Resembling miniature mushrooms, these fruiting bodies consist of both a freestanding stalk and the spores that sit atop it. Ultimately, the spores are carried away, commonly on the legs of passing creatures, to start the life cycle all over again. But in order to disperse the spores, some of the colony's individuals must altruistically sacrifice themselves in order to make the stalk......... Posted by: Erica Permalink Source Brave new world in life sciences
Writing in the September/October Bulletin, the authors argue that fixing a fractured public health system to be responsive to "both natural and deliberate biological threats" is perhaps "the most obvious and important" of the recommendations coming from the report produced by a committee of the National Research Council/Institute of Medicine (IOM). Eileen R. Choffnes, director of the IOM's Forum on Microbial Threats; Stanley M. Lemon, forum chair and director of the Institute of Human Infections and Immunity at the University of Texas, Galveston; and David A. Relman, associate professor of microbiology and immunology and of medicine at Stanford University, were the study director and co-chairs, respectively, of the committee. Also in this issue of the Bulletin: Two different assessments of U.S. vulnerability to nuclear terrorism. Graham Allison, director of the Belfer Center for Science and International Affairs at Harvard's John F. Kennedy School of Government, warns that Americans are "more vulnerable to a nuclear 9/11 today than we were five years ago." William M. Arkin, online columnist for the Washington Post and author of upcoming The Alternative: Terrorism, Weapons of Mass Destruction, and the American Future, argues that the nuclear terrorism threat has diminished, and that exaggerated fears of a nuclear 9/11 have prompted the United States to divert crucial resources toward failed policies......... Posted by: Kelly Permalink Source Persicaria Amplexicaulis
'Firetail' red bistort or mountain fleece is an RHS Award of Garden Merit plant. For gardening info about this plant, visit the MBG's Kemper Center for Home Gardening. Botany resource link: The blooming of Amorphophallus titanum at Brooklyn Botanic Garden, suggested by Karen V, a BPotD commenter......... Posted by: Erica Permalink Source Strawberry Flowers, Forever
Did anyone remember it was the Wimbledon men's finals yesterday? I disgracefully forgot, and was reminded only as I digested an indulgent dessert of strawberries and cream before going to watch Les Bleus not exactly 'allez' across the football pitch. But I think I kind of made up for it, because for most of the time I was watching the French amble slowly toward defeat, I was thinking more about Wimbledon than about the World Cup: I was speculating about strawberries. And not because my dessert was playing havoc with my digestive tract, either. My interest was more professional than personal. I wanted to know about the strawberry's lineage. After a bit of research, I discovered that not only is the strawberry not a berry (eventhough tomatoes are), but a close cousin of the rose: the fragaria from the Rosaceae family, to be precise. Once the little white flowers, which look strikingly like miniature dog roses, have been pollinated, the stems develop the squisy red fruits that have become the traditional snack of summer tennis - and apparently over 27,000 kg of strawberries are eaten at Wimbledon each year!........ Posted by: Erica Permalink Source Biologist Trying To Crack Microscopic Code
"Proteins interact; they 'talk' to each other," the associate professor says. "It's how they know what to do, and it's how most of the things that need to happen for living organisms get done." Over the past three years he has received $300,000 in funding from the National Science Foundation for his research. What talking proteins have to do with infectious disease is a story that unfolds in the submicroscopic world of molecular biology. It starts with bacteria, which are cloaked by an outer membrane--a defensive barrier against the harsh elements of their environment, whether toxins in nature or the protective antibodies of an infected host. Specific proteins interact to support this shield, and knowing how they communicate would provide a key to disabling it, Larsen says. Once communication questions are answered, a goal is to develop drugs to break the barrier, rendering the bacteria more susceptible to the human body's natural defenses--antibodies--as well as certain antibiotics, he points out. While keeping potential dangers out, the outer membrane must also be porous enough to allow nutrients in, he continues. As an analogy, he cites a house with a yard and a chain-link fence that "keeps the dogs out of the roses but lets the butterflies through"......... Posted by: Kelly Permalink Source Ocean Noise Has Increased Considerably
Sean Wiggins (left) and John Hildebrand deploy listening devices at various locations around the world. This instrument was recovered in the Gulf of California.
New research reported in the recent issue of the Journal of the Acoustical Society of America (JASA) has shown a tenfold increase in underwater ocean noise off Southern California's coast as compared with the 1960s. Mark McDonald of WhaleAcoustics in Bellvue, Colo., and John Hildebrand and Sean Wiggins of Scripps Oceanography accessed acoustic data recorded in 1964-1966 through declassified U.S. Navy documents and compared them against acoustic recordings made in 2003-2004 in the same area off San Nicolas Island, one of the Channel Islands more than 160 miles west of San Diego. The results showed that noise levels in 2003-2004 were 10 to 12 decibels higher than in 1964-1966, an average noise increase rate of three decibels per decade. The culprit behind the increase, as per Hildebrand, appears to be a byproduct of the vast increase in the global shipping trade, the number of ships plying the world's oceans and the higher speeds and propulsion power for individual ships. The noise detected off Southern California originates from ships traveling across the entire North Pacific Ocean. As per Lloyd's Register figures quoted in the JASA paper, the world's commercial fleet more than doubled in the past 38 years, from 41,865 in 1965 to 89,899 in 2003......... Posted by: Kelly Permalink Source Bacteria Can Help Predict Ocean Change
Researchers have long endorsed the concept of a unique biological niche for most animals and plants a shark, for example, has a different role than a dolphin. Bacteria instead have been relegated to an also-ran world of "functional redundancy" in which few species are considered unique, said Jed Fuhrman, holder of the McCulloch-Crosby Chair in Marine Biology in the USC College of Letters, Arts and Sciences. In The Proceedings of the National Academy of Sciences' Early Edition, Fuhrman and his colleagues from USC and Columbia University show that most kinds of bacteria are not interchangeable and that each thrives under predictable conditions and at predictable times. On the other hand, the kinds and numbers of bacteria in a sample can show where and when it was taken. "I could tell you what month it is if you just got me a sample of water from out there," Fuhrman said. The scientists took monthly bacteria samples for more than four years in the Pacific Ocean near the USC Wrigley Institute's marine laboratory on Catalina Island. They used statistical methods to correlate the bacteria counts with the Wrigley Institute's monthly measurements of water temperature, salinity, nutrient content, plant matter and other variables......... Posted by: Kelly Permalink Source |
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