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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, 2012Natureavian predator, ladybird colour, ladybirds, pigment levels, pigmentation, warning signals

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

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…)

Moonlighting Enzyme Works Double Shift 24/7

By Guest PostFebruary 1, 2012Nature, Sciencearabidopsis, atp synthase, building block, chloroplast, david Kramer, energy, france, gamma, Germany, michigan state university, moonlighting enzyme, new function, nutrient, photosynthesis, plant enzyme, protein, root, root hair, subunit

EAST LANSING, Mich. — A team of researchers led by Michigan State University has discovered an overachieving plant enzyme that works both the day and night shifts.

The discovery, featured in the current issue of Proceedings of the National Academies of Science, shows that plants evolved a new function for this enzyme by changing merely one of its protein building blocks. (more…)

Severe Declines in Everglades Mammals Linked to Pythons

By Guest PostJanuary 31, 2012Environment, Natureafrican python, alex wolf, alligators, america, beni anaconda, boa constrictor, bobcat, burmese python, camp walker, christopher gillette, cottontail rabbits, dan kimball, deschauensee anaconda, ecological impact, ecosystem, everglades, everglades ecosystem, everglades national park, everglades python, fox, geographic pattern, green anaconda, invasive species, john willson, mammal decline, mammals, marcia mcnutt, marsh, michael dorcas, michael rochford, national park, opossums, prey, python, python predation, rabbits, raccoons, robert reed, spread of pythons, therese walters, U.S. Geological Survey, united states

HOMESTEAD, Fla. — Precipitous declines in formerly common mammals in Everglades National Park have been linked to the presence of invasive Burmese pythons, according to a study published on Jan. 30, 2012, in the Proceedings of the National Academy of Sciences.

The study, the first to document the ecological impacts of this invasive species, strongly supports that animal communities in this 1.5-million-acre park have been markedly altered by the introduction of pythons within 11 years of their establishment as an invasive species. Mid-sized mammals are the most dramatically affected. (more…)

Monogamous Birds….Peeping on the Neighbours!

By Guest PostJanuary 28, 2012Naturecolourful plumage, courtship dance, disease, dominique drullion, female, female zebra finche, frederique dubois, hypothesis, immunosuppressive effect, laboratory, male bird, male genetic quality, monogamous species, public information, reproduction period, sexual selection, social environment, song, testosterone, zebra finch

It is well documented that male birds seduce females using their songs, colourful plumage and courtship dances. These signals reflect male genetic quality and will be graded by the female to determine a male’s potential as a mate. The stronger the grade, the better the odds of being selected.

But this basic rule isn’t the only yardstick used by females. As surprising as it seems, birds know how to use data from their social environment to maximize their chances of reproduction. Frédérique Dubois, a professor at the Université de Montréal Department of Biological Sciences, has already demonstrated that female Zebra Finches will favour a male chosen by another female. Dubois refers to this as imitation and the use of “public information” in choosing a mate. (more…)

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