Pollination from the plant’s perspective

If plants had a perspective, they would probably think of pollinators as more than just extra-friendly house guests. That is, plants would be more likely to view pollinators as the mutual friend who likes to set up blind dates. Bees might limit pollen to its use as a protein source for the hive, and birds might devour the flesh of a fruit and eliminate the seed as waste. However, many flowering plants, as Bug Girl pointed out in a post in honor of National Pollinator Week, have evolved alongside these pollinators for only one purpose: reproduction. “Sure, you can toss your pollen out on the wind and hope it lands in the right place. And for a lot of plants, evergreens in particular, this works just fine,” she wrote. “That methodology results in a lot of wasted gametes (plant sperm) though, so for nearly all flowering plants, insects or other pollinators are needed for plant nookie.” Sometimes the pollinator-plant relationship is mutualistic, and in many cases, one species or another is dependent upon the other for its survival. Take the agave plant. Probably the most well-known species is the blue agave plant (Agave tequilana), the nectar of which is used as a granular sugar substitute and to make tequila (one of the “finer” products of pollination, along with chocolate and coffee, mentioned by Bug Girl ). Leptonycteris nivalis, known as the greater long-nosed bat or Mexican long-nosed bat, and the lesser long-nosed bat (Leptonycteris curasoae), are the primary pollinators of this economically and ecologically valuable plant. This agave-bat relationship is mutually beneficial. The bats, hovering in place like a hummingbird, use their long muzzles to feed on the high-fructose nectar of the agave. At the same time, the plants’ pollen collects on the bats’ fur. The bats then travel from plant to plant, spreading pollen as they drink from the nectar-filled stalks that bloom each night across the southwestern U.S. and Mexico. The bats also migrate based on the blooming time of these plants. They arrive in Texas—particularly in Big Bend National Park, where a single colony resides in the Chisos Mountains—shortly after agave plants, such as the century plant (Agave havardiana), begin to bloom. Unfortunately, the lesser long-nosed bat and the Mexican long-nosed bat are endangered—and as their numbers decline, agave plant reproduction becomes more limited. A little farther north, however, some species of agave plants—those that are not harvested for tequila— have evolved to attract both bats and moths to serve as pollinators. Agave plants have several ways of advertising their nectar: the scent, the color of the flower and the shape, or morphology, of the structure...

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The evolution of beer yeasts, seedy pants and vampire bat venom-turned medicine

Beer yeasts: Researchers at Lund University in Sweden tracked the history of two yeasts—Saccharomyces cerevisiae and Dekkera bruxellensis—used in alcohol fermentation to pinpoint their role in ethanol production. They found that, around 150 million years ago, competition with other microbes, and the overall increase in sugar-rich fruits, encouraged the yeasts to withstand high ethanol concentrations—an adaptation that would allow them to survive in places other microbes could not. “Now, scientists are closing in on just how and why yeast evolved to [ferment sugars into alcohol],” wrote John Roach in an MSNBC article. “No, it wasn’t to get humans drunk.” Read more at “The why of yeast’s buzz-giving ways” or the press release “Wine yeasts reveal prehistoric microbial world.” Camouflaged cuttlefish: “Cuttlefish are masters of camouflage. Like their relatives, the squid and the octopus, cuttlefish can change the colour of their skin to perfectly match a bed of pebbles, a clump of algae, or a black-and-white chessboard,” wrote Ed Yong of Not Exactly Rocket Science (see below video of previous research). Alexandra Barbosa from the University of Porto found that cuttlefish use visual cues to alter their appendages as well. In other words, when the cephalopods were placed against backgrounds of various striped patterns, they adjusted their tentacles to match the pattern that they saw. Read more and see photos at “Pocket Science – will all camouflaged cuttlefish please raise their tentacles?” Seedy pants: One of the most topical quotes this week—“I wish nature would stop getting it on in my eyeballs”—was uttered by a fellow allergy sufferer. Allergy season is in full force in temperate locales, such as some parts of the U.S. East Coast, as trees flood the air with pollen in the hopes of reaching a female counterpart. There are several ways that pollen travels, such as the wind, but most of us have probably never considered the role of pants in tree pollination. Yes, pants not plants. As quoted in a recent NPR article, “‘Because of his great mobility,’ [British botanist Edward] Salisbury wrote (projecting from his personal data set), ‘man is probably the most active agent—though usually an unconscious one—for [the] external transport of seeds.’” Read more at “Strange Things Happen To Guys Who Wear Pants.” Vampire bat venom: Scientists have tapped vampire bat saliva as a potential medication for treating stroke in humans, and the drug is actually called “Draculin.” It was announced this week that the drug would enter Phase 2 tests. “When vampire bats bite their victims, their saliva releases an enzyme called desmoteplase, or DSPA, into the bloodstream, which causes blood to flow more readily,” wrote Patrick Morgan on Discover’s blog...

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From the Community: shark science, reconciliation ecology and Biodiversity 100

An analysis of Shark Week, research on reconciliation ecology from ESA’s annual meeting, flowers that are genetically predisposed to adapting to climate change, endangered, purring tit monkey species found in Colombia amidst violence and the details on the antibiotic-resistant “superbug.” Here is the latest in ecological science from the second week in August.

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From the Community: Giant monitor lizard, seafloor scavengers and fruit fly aerodynamics

Climate change prompts migratory birds to stay home, Simpsons’ writer talks conservation and the U.K. announces newest and largest MPA. Here’s what is happening in ecology from the second week in April.

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The phrenologist’s guide to ecological competence

Since Darwin, scientists have been theorizing as to why there is variation in brain size between species and individuals. Does a larger brain, in say humans, indicate advanced cognitive abilities and complex language processing? Or is a smaller brain, such as the Olive-backed thrush’s, adapted to weigh less to accommodate lengthy flights?

In psychology, the field of phrenology has generally been dissolved, and with it, the idea that variations in brain size could indicate differences in intelligence, creativity or personality between humans. In the field of biology, however, scientists are discovering that brain variation across species might actually be linked to ecological competence. In this case, ecological competence describes the efficiency of a species to engage in ecological processes—such as flexible foraging abilities or advanced spatial memory for migration.

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Large seeds take the advantage in stressful conditions

The coconut tree’s large seed is better adapted to drought and shade than smaller seeds. It is generally believed that, when competing for the same resources, large plant seeds beat out small seeds regardless of the growing conditions. But according to researchers at the Smithsonian Tropical Research Institute, large seeds actually have the advantage in stressful conditions—such as during a drought or in the shade—while small seeds thrive in abundant sun and water. The study, published in this week’s edition of the Proceedings of the National Academy of Sciences, explains the evolutionary advantages of producing large, tolerant seeds versus a large amount of small seeds. This variation, says the study’s author Helene Muller-Landau, allows species to coexist  in regeneration sites that vary in stressfulness. http://www.flickr.com/photos/madbuster75/ / CC BY-NC-ND 2.0 Muller-Landau, H. (2010). The tolerance-fecundity trade-off and the maintenance of diversity in seed size Proceedings of the National Academy of Sciences DOI:...

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Sunbathing: good for your bones (if you’re a lizard)

Cold-blooded animals don’t produce their own heat, and thus they must sunbathe, basking in the sun’s rays to raise their body temperatures so they have eonugh energy to  go about their business. But for some ectotherms, the sun isn’t just a source of heat.  A new study shows that in the panther chameleon, native to Madagascar, basking behavior also controls production of essential vitamin D. In reptiles, vitamin D3 chaperones calcium in and out of the blood, and so is important for the production of strong bones. Insects, the lizards’ preferred meal, don’t provide much vitamin D; however, exposure to sufficient UV radiation triggers production of the essential vitamin in lizards’ skin. So when D levels drop, sunning squamates adjust their behavior to soak up more daylight. Kristopher Karsten of Texas Christian University and his colleagues fed one group of chameleons crickets dusted with vitamin D powder, and fed another group plain old crickets. In outdoor trials, the plain-cricket lizards basked for longer periods of time than the D-supplemented lizards. The most interesting thing about this study is perhaps not the fact that lizards control their internal vitamin D, since there’s a growing understanding that lizards bask for many other reasons than just thermoregulation, such as visibility and mating. The more compelling bit is the accuracy and precision with which the lizards control their vitamin D. Within groups, the lizards showed very little variation in realized D levels. Like body temperature, which for most lizards has a narrow optimal range, D levels are probably under strong selection for an optimum, above or below which the lizards don’t achieve the best possible bone strength. Karsten, K., Ferguson, G., Chen, T., & Holick, M. (2009). Panther Chameleons, Furcifer pardalis, Behaviorally Regulate Optimal Exposure to UV Depending on Dietary Vitamin D3 StatusPhysiological and Biochemical Zoology, 82 (3), 218-225 DOI:...

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Happy Birthday, Charles Darwin

Today we mark the 200th anniversary of the birth of the most influential thinker in biology, Charles Darwin, renowned as the founder of the theory of evolution by natural selection. Publications worldwide have commemorated the day by publishing news articles on Darwin’s life and work and the current state of affairs in evolutionary theory.  Here’s a selection of impressive ones. Darwin Speaks, Scientific American. An ‘interview’ with Darwin himself, where the naturalist fields questions about his early life, his convictions and most interestingly the evolution of his own ideas about faith. Going Where Darwin Feared To Tread, The Washington Post. A treatment of the issue Darwin feared to tackle in 1859, but would later take up in “The Descent of Man”: the evolution of the human race. This article ran on the front page. Darwinism Must Die So That Evolution May Live, The New York Times. This essay by Carl Safina calls attention to the fact that Darwinism is rather cultish in itself, and that most people can’t (or, in the case of some scientists, don’t) distinguish the proecess of evolution from the advances of the man himself.  He highlights the huge advances in evolutionary theory over the past 150 years. On ‘Darwin Day’, Many Americans Beg To Differ, The Christian Science Monitor. A reality check into the fact that more than 40 percent of Americans believe that life on Earth existed in its current form since the beginning of time. The unbiased article reveals that anti-evoution groups are staging their own commemoration today, calling it “Academic Freedom Day”. Six Sites That Are Galapagos for Modern Darwins, Discover magazine. A rundown of six modern study sites that have gained attention for the discovery of rapid (and/or charismatic) evolution Happy Birthday, Mr. Darwin, Science special issue. This article is the introduction to a special issue of Science to commemorate the anniversary.  The issue includes review papers by great modern ecological and evolutionary thinkers, including Dolph Schluter and Jonathan Losos. Darwin Find Some Followers in the Pulpits, NPR. An inspirational article about belief in evolution among clergy and the associated Evolution Weekend initiative and its associated Clergy Letter project, in which more than 11,000 clerics across the U.S. have signed on to a letter stating that “those claiming that people must choose between religion and science are creating a false dichotomy.” Darwin Day in the U.K., The Guardian. A listing of some of the hundreds of events going on to celebrate Darwin Day in the...

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