Nature – Page 99 – Shamskm: A site to exchange knowledge and solutions

Building A Better Trap

By Guest PostFebruary 19, 2012Naturebuilding a trap, collecting insects, led modified trap, leds, light emitting diodes, new trap, sand flies

Fieldwork in Peru’s Andes Mountains is demanding, especially when it involves hauling heavy equipment to remote sites that are accessible only by traversing the region’s rugged terrain. (more…)

Fish of Antarctica Threatened by Climate Change

By Guest PostFebruary 16, 2012Environment, Natureantarctic fish, antarctic fish lineage, anti freeze proteins, antifreeze glycoproteins, climate change, evolution of antifreeze, polar conditions

A Yale-led study of the evolutionary history of Antarctic fish and their “anti-freeze” proteins illustrates how tens of millions of years ago a lineage of fish adapted to newly formed polar conditions – and how today they are endangered by a rapid rise in ocean temperatures. (more…)

Scared of a Younger Rival? Not for Some Male Songbirds

By Guest PostFebruary 14, 2012Naturemale birds, male songbirds, mature sparrow, nesting territory

COLUMBUS, Ohio — When mature male white-crowned sparrows duel to win a mate or a nesting territory, a young bird just doesn’t get much respect. (more…)

Bird Count

By Guest PostFebruary 12, 2012Naturebackyard feeder, baltimore oriole, bird count, bird nerd, boreal forests, charles shattuck, chris williams, delaware nature society, derek stoner, kennett square, laysan albatross, margo mcdonough, pine siskins, red breasted nuthatches, red clay creek, screech owl

*Birds aren’t flocking to backyard feeders this winter*

What’s in short supply this winter? If you said snow you guessed the first (and obvious) answer. But you may not have noticed what else has been scarce — birds at backyard feeders.

“Our customers are talking about the fact that fewer birds are coming to feeders this winter,” says Charles Shattuck who, with his wife, Kathy, owns Wild Birds Unlimited in Hockessin. “I’ve heard reports of fewer birds at feeders across the East Coast.” (more…)

Redder Ladybirds More Deadly, Say Scientists

By Guest PostFebruary 7, 2012Naturearms race, colour, defensive chemical, ecologist, jon blount, ladybird, liverpool, mike speed, pigmentation, poisonous, precoccinelline, predator, redder wings, signals of animals, spot ladybird, toxic, toxicity, universitiy of exeter, warning signal

A ladybird’s colour indicates how well-fed and how toxic it is, according to an international team of scientists.

Research led by the Universities of Exeter and Liverpool directly shows that differences between animals’ warning signals reveal how poisonous individuals are to predators.

Published in the journal Functional Ecology, the research shows that redder ladybirds are more poisonous than their paler peers. The study reveals that this variation is directly linked to diet in early life, with better-fed ladybirds being more visible and more deadly.

Ecologists have long assumed that there are no individual differences between the warning signals of animals of the same species. More recently, scientists have identified variation between individuals’ warning signals, but have not known if these differences were meaningful and linked to levels of toxicity. (more…)

A Bug’s (Sex) Life: Diving Beetles Offer Clues About Sexual Selection

By Guest PostFebruary 6, 2012Nature, Sciencearizona desert, co evolution, dawn higginson, diving beetles, dytiscidae, epifluorescence image, Europe, evolution, evolutionary relationship, female, fertilization, great diving beetle, hygrotus sayi, invertebrate, kari segraves, kelly miller, larva, male, mammal, mollusk, reproductive organ, scott pitnick, sexual evolution, sexual selection, sexual trait, speciation, sperm evolution, sperm storage, spermatheca, syracuse university, thermonectus marmoratus, university of arizona

*Studies of diving beetles suggest sperm evolution may be driven by changes in female reproductive organs, challenging the paradigm of post-mating sexual selection being driven mostly by competition among sperm.*

Studying female reproductive tracts and sperm in diving beetles (Dytiscidae), researchers from the University of Arizona and Syracuse University have obtained a glimpse into a bizarre and amazing world of sperm that can take on a variety of forms – including joining together into conglomerates that navigate the twisted mazes of the female reproductive tract.

Analyses of the evolutionary relationships among diving beetles reveal that sperm form appears to follow function dictated by female reproductive organs. (more…)

First Plants Caused Ice Ages

By Guest PostFebruary 1, 2012Environment, Natureatmospheric carbon, atmospheric carbon level, calcium, carbon cycle, carbonate rocks, chemical weathering, climate, earth surface, first land plants, global cooling, granite, ice ages, iron, liam dolan, magnesium, marine life, mass extinction, mineral, modern moss, ocean, ordovician period, oxford university, phosphorus, physcomitrella patens, reduction, rocks, silicate rocks, tim lenton, university of exeter

*New research reveals how the arrival of the first plants 470 million years ago triggered a series of ice ages. Led by the Universities of Exeter and Oxford, the study is published in Nature Geoscience.*

The team set out to identify the effects that the first land plants had on the climate during the Ordovician Period, which ended 444 million years ago. During this period the climate gradually cooled, leading to a series of ‘ice ages’. This global cooling was caused by a dramatic reduction in atmospheric carbon, which this research now suggests was triggered by the arrival of plants.

Among the first plants to grow on land were the ancestors of mosses that grow today. This study shows that they extracted minerals such as calcium, magnesium, phosphorus and iron from rocks in order to grow. In so doing, they caused chemical weathering of the Earth’s surface. This had a dramatic impact on the global carbon cycle and subsequently on the climate. It could also have led to a mass extinction of marine life. (more…)

New Species of Ancient Crocodile, Ancestor of Today’s Species, Discovered by MU Researcher

By Guest PostFebruary 1, 2012Nature, Scienceaegisuchus witmeri, age of the crocs, age of the dinosaurs, ancestor, casey holliday, crocodilians, fossilized skull, late cretaceous period, mesozoic era, modern crocodile, nick gardner, prehistoric crocodile, shieldcroc, species, thermo regulator

COLUMBIA, Mo. – A University of Missouri researcher has identified a new species of prehistoric crocodile. The extinct creature, nicknamed “Shieldcroc” due to a thick-skinned shield on its head, is an ancestor of today’s crocodiles. Its discovery provides scientists with additional information about the evolution of crocodiles and how scientists can gain insight into ways to protect the species’ environment and help prevent extinction. The discovery was published this week in the journal PLoS-ONE (Public Library of Science). (more…)

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