darwin – Shamskm: A site to exchange knowledge and solutions

Is Self-Fumigation for the Birds?

By Guest PostJune 4, 2014Natureanthony straub, better workday, bilder, biologists, birds, darwin, ecuador, endangered species, floreana island, galapagos islands, guernica, hashed passwords, hurricane andrew, hydrophobic polymer nanofibers, isabela island, japanese volcano, kim cameron, king solomon, malerei, mammals, monika fink, nanobubble membrane, nashorn handel, north atlantic hurricanes, sakurajima volcano, santa cruz island, schwarzmarkt, siyuan xian, university of utah, user account, yahoo users

Save Threatened Species by Giving Them Treated Cotton for Nests

When University of Utah biologists set out cotton balls treated with a mild pesticide, wild finches in the Galapagos Islands used the cotton to help build their nests, killing parasitic fly maggots to protect baby birds. The researchers say the self-fumigation method may help endangered birds and even some mammals.

“We are trying to help birds help themselves,” says biology professor Dale Clayton, senior author of a study outlining the new technique. The findings were published online May 5, 2014, in the journal Current Biology. (more…)

Deep in Texas, a plant-eating feathered dinosaur reemerges

By Guest PostMay 1, 2013Scienceaguja formation, asia, big bend, bird like caenagnathids, caenagnathus collinsi, carnivorous cousin velociraptor, darwin, deep in texas, dinosaur texacephale, evolutionary history, extinct dinosaurs, feathered dinosaur, fossil, ken barnes, larry millar, leptorhynchos, leptorhynchos elegans, leptorhynchos gaddisi, little jaw, national park, natural history, nicholas r longrich, North America, north american caenagnathids, peabody museum, plant eating, scott clark, species, terlingua, turkey sized herbivore, utah, west texas, western canada, yale university

A recently identified feathered dinosaur found deep in West Texas reinforces an emerging view that creatures like it were more diverse and widespread in North America than previously thought, according to a new study.

The species — a turkey-sized herbivore called Leptorhynchos gaddisi — belongs to a broader group of bird-like dinosaurs characterized by toothless beaks and long, slender claws, said researchers, who analyzed fossils found near Big Bend National Park at a site dating to about 75 million years ago. (more…)

Gardener’s Delight Offers Glimpse into the Evolution of Flowering Plants

By Guest PostSeptember 5, 2012Nature, Sciencealessandra sullivan, ancient lineage, anemonella thalictroides, antirrhinum majus, arabidopsis thaliana, blossoms, carpels, darwin, di stilio lab, double dandy peony, double peppermint petunia, doubled strawberry, eudicots, family ranunculaceae, flower, flower diversification, flowering species, function, gene, genetic interruption, geologic time, gunter theissen, kelsey galimba, mutant, mutation, northeastern us, period, petal, pink, plant, plant model, rainer melzer, rose, rue anemone, seed production, sexual organ, sexual reproduction, snapdragon, thalictrum, theadora tolkin, vanilla lily, veronica di stilio

The Pink Double Dandy peony, the Double Peppermint petunia, the Doubled Strawberry Vanilla lily and nearly all roses are varieties cultivated for their double flowers.

The blossoms of these and other such plants are lush with extra petals in place of the parts of the flower needed for sexual reproduction and seed production, meaning double flowers – though beautiful – are mutants and usually sterile.

The genetic interruption that causes that mutation helped scientists in the 1990s pinpoint the genes responsible for normal development of sexual organs stamens and carpels in the plant Arabidopsis thaliana, long used as a plant model by biologists. (more…)

Biologists Turn Back the Clock to Understand Evolution of Sex Differences

By Guest PostMay 9, 2012Nature, Scienceabderrahman khila, antlers, battle, darwin, ehab abouheif, evolution, hooks, locke rowe, male guppies, mating, mcgill university, moose, peacocks, plumage, rheumatobates rileyi, rna interference, sex differences, sexes, traits in nature, tusks, university of toronto, walruses, water striders, wild colours

Battles of sexes shown to spur adaptive sex differences

Sex differences account for some of the most of the spectacular traits in nature: the wild colours of male guppies, the plumage of peacocks, tusks on walruses and antlers on moose. Sexual conflict – the battle between males and females over mating – is thought to be a particularly potent force in driving the evolution of traits that differ in males and females.

However, the genetic processes responsible for producing such traits are not well understood, nor how they evolved from their simpler less elaborate ancestral forms. We tend to assume that each tiny step in evolution is an advantage. But are they really? (more…)

Scientists Trace Evolutionary History of What Mammals Eat

By Guest PostApril 17, 2012Nature, Scienceanimal ecology, antelope, bats, big cats, carnivory, cows, darwin, davis, deer, duke university, environmental biology, evolutionary race, evolutionary time, extinct, feeding habit, george gilchrist, herbivory, louise roth, macroevolutionary diversification, mammal, meat, national science foundation, omnivore, plant eater, primates, rabbits, rodents, samantha hopkins, samantha price, ungulates, university of california, university of oregon

*Feeding habits haven’t always been what they are today*

The feeding habits of mammals haven’t always been what they are today, particularly for omnivores.

Some groups of mammals almost exclusively eat meat–take lions and tigers and other big cats as examples.

Other mammals such as deer, cows and antelope are predominantly plant-eaters, living on a diet of leaves, shoots, fruits and bark. (more…)

Biodiversity improves water quality in streams through a division of labor

By Guest PostApril 7, 2011Environmentbiodiversity, biologically diverse streams, bradley cardinal, chesapeake bay, darwin, Environment, flow conditions, great lakes, model streams, molded plastic, natural streams, nitrate, nutrient pollutant, pollutant filters, pollutants

ANN ARBOR, Mich.— Biologically diverse streams are better at cleaning up pollutants than less rich waterways, and a University of Michigan ecologist says he has uncovered the long-sought mechanism that explains why this is so.

Bradley Cardinale used 150 miniature model streams, which use recirculating water in flumes to mimic the variety of flow conditions found in natural streams. He grew between one and eight species of algae in each of the mini-streams, then measured each algae community’s ability to soak up nitrate, a nitrogen compound that is a nutrient pollutant of global concern. (more…)

Tag Archives: darwin