NEWS

Blog post in Oikos blog about the phylosophy behind the Oikos paper "Colony size and foraging range in seabirds" Selected by R Jovani
Study Projects How Climate Change Will Affect the Functions Birds in Ecosystems Worldwide SciTech Daily (Global Change Biology paper) Selected by JL Alcantara
Swift Incredible Journey Selected by R Jovani
Flowers make the menu for nearly all Galapagos birds Science News (Nature Communications paper) Selected by JL Alcantara
Habitat degradation and climate shifts impact survival of the white-collared manakin EurekAlert! (Oecologia paper) Selected by JL Alcantara
Birds flying in a V take turns in the top spot, study finds Los Angeles Times-Science (PNAS paper) Selected by JL Alcantara Play the caterpillar defense National geographic (American Naturalist paper) Selected by J Broggi
Darwin 2.0: Scientists shed new light on how species diverge Phys.org (Nature paper) Selected by JL Alcantara
Agriculture Is Reshaping the Avian Tree of Life American Scientist (Science paper) Selected by JL Alcantara Fatal Attraction of Short-Tailed Shearwaters to Artificial Lights Science daily ( PloS One paper) Selected by J Broggi
Winter bird feeders: Get ready for a busy season Science/AAAS (Global Change Biology paper) Selected by JL Alcantara
Dinosaur family tree gives fresh insight into rapid rise of birds Phys.org (Current Biology paper) Selected by JL Alcantara
Migrating birds sprint in spring, but take things easy in autumn ScienceDaily (Behavioral Ecology and Sociobiology paper) Selected by Jose L. Alcantara
Hummingbirds evolved a strange taste for sugar ScienceNews (Science paper) Selected by JL Alcantara
Group foraging in little penguins ScienceDaily ( PLoS ONE paper) Selected by R Jovani
Mixed Genes Mix Up the Migrations of Hybrid Birds ScienceNewsline (Ecology Letters paper) Selected by JL Alcantara
Dinosaurs 'shrank' regularly to become birds BBC (Science paper) Selected by JL Alcantara
Parrot Who Was Among Last of Its Kind, Said to Have Inspired ‘Rio,’ Dies National Geographic Society Selected by JL Alcantara
Researchers declassify dinosaurs as being the great-great-grandparents of birds Phys.org (Journal of Ornithology paper) Selected by JL Alcantara
Pristine fossil confirms Archaeopteryx as original bird United Press International (Nature paper) Selected by JL Alcantara
All gone: How erasing billions of birds shocked us Yahoo! News (PNAS paper) Selected by JL Alcantara
Plants hitch a lift on migrating birds BBC Nature (PeerJ paper) Selected by JL Alcantara
Mapping the evolution of a ring species Univ. British Columbbia (Nature paper) Selected by R Jovani
Closest Living Relative of Ancient Elephant Bird Is Tiny LiveScience (Science paper) Selected by JL Alcantara
Identifying evolutionary distinct birds WIRED (Current Biology paper) Selected by R Jovani
Ten Thousand Birds: Ornithology since Darwin Myriad Birds Selected by JL Alcantara
The 100 most distinct and rare birds BBC Nature (Current Biology paper) Selected by JL Alcantara
Hummingbird Evolution Soared After They Invaded South America 22 Million Years Ago ScienceNewsline (Current Biology paper) Selected by JL Alcantara
Bird’s Extinction Is Tied to the Arrival of Humans The New York Times (PNAS paper) Selected by JL Alcantara
A bird-like dinosaur called “Chicken from Hell” NPR news (PLOS One paper) Selected by JL Alcantara
Wintering irruptions of Snowy owls in North America and Europe (in Spanish) SEO/BirdLife blog Selected by R Jovani
Punk Amazon pheasant is a European emigrant NewScientists (Naturwissenschaften paper) Selected by JL Alcantara
Flights of Fancy in Avian Evolution American Scientist Selected by JL Alcantara Why do birds fly in a V? Endangered ibis reveals its amazing secret (VIDEO) Los Angeles Times (Nature letter) Selected by J Broggi
Sharp-toothed tigerfish jumps to eat a bird (VIDEO) (J Fish Biol paper) Nature News Selected by J Broggi
On the evolution of bird fingers. PHYS.ORG (J Exp Zool paper) Selected by R Jovani
Albatross colony shows benefits of same-sex pairing ABC Science (J Proceedings of the Royal Society B paper) Selected by JL Alcantara Swifts stay airborne for six months at a time New scientist(Nature communications paper) Selected by J Broggi
100 years ago bird lovers were encouraged to use the field glasses rather than the gun The Guardian Selected by R Jovani
Trees send distress signals that birds use to find insects Sinc(Ecol Lett paper) Selected by R Jovani
I’m singing in the rainforest Max-Planck-Gesellschaft (journal of interdisciplinary music studies paper) Selected by JL Alcantara
Fossil Poo Reveals Where Ancient Giant Bird Ate Discovery News (PNAS paper) Selected by JL Alcantara
Colonizing songbirds lost sense of syntax e! Science News (Current Biology paper) Selected by JL Alcantara
Songbirds may have 'borrowed' DNA to fuel migration Phys.org (Evolution paper) Selected by JL Alcantara
Collision Course ScienceNews (ScienceNews paper) Selected by JL Alcantara
Social learning of migratory performance PhysOrg (Science paper) Selected by R Jovani
Evolution of parasitic egg colouration: parasites also select. Not Exactly Rocket Science blog(Biol Lett paper) Selected by R Jovani
European birds adjust their flight initiation distance to road speed limits BBC News(Biol Lett paper) Selected by R Jovani
The secret of male beauty (in turkeys) UCL News (PLOS Genetics paper) Selected by JL Alcantara
Bird hunters 'emptying Afghan skies' BBC News Asia Selected by JL Alcantara
Secrets of the world’s toughest little bird Griffith U. News (Nature Communications paper) Selected by JL Alcantara Outdoor Cats: Single Greatest Source of Human-Caused Mortality for Birds and Mammals American Bird Conservancy (Nature communications paper) Selected by J Broggi
Hiding in plain sight: New species of bird discovered in capital city e! Science News (Forktail paper) Selected by JL Alcantara
Foraging space partitioning without territoriality in a seabird ScienceDaily (Science paper) Selected by R Jovani
Bird extinction leads to rapid evolution of seed size The Red Notebook (Science paper) Selected by R Jovani
Bird song changes in translocated birds ScienceDaily (J Appl Ecol paper) Selected by R Jovani
Why penguins lost their wings ABC Science (PNAS paper) Selected by JL Alcantara
Simulated patternity uncertainty: Males care about intruders but feed nestlings regardless of patternity uncertainty ScienceDaily (PLoS ONE paper) Selected by R Jovani
Seabird Bones Reveal Changes in Open-Ocean Food Chain Science Daily(PNAS paper) Selected by F Mateos-Gonzalez
New fossil brings new light on the evolution of hummingbirds and swifts Science NOW(Proc R Soc B paper) Selected by R Jovani
Testosterone vs. audience on the regulation of bird fights and social status ScienceDaily (Hormones and Behavior paper) Selected by R Jovani
Lead bullet fragments poison rare US condors BBC News Selected by JL Alcantara
Avoiding cuckoo parasitism by breeding indoors Live Science(Beh Ecol Sociobiol paper) Selected by R Jovani
Why I study duck genitalia... or... why basic science matters Slate Selected by R Jovani
A study about play in cranes BBC Nature(Ibis paper) Selected by R Jovani
Pretty great tits make better mothers Discover (Frontiers in Zoology paper) Selected by JL Alcantara
Humans wiped out Pacific island birds ABC Science (PNAS paper) Selected by JL Alcantara
The Rise and Fall of Four-Winged Birds Not Exactly Rocket Science (Science paper) Selected by R Jovani
Sex role reversal: Female shorebirds rule the roost BBC News (Nature Communications paper) Selected by JL Alcantara
Birds communicate their size through song ScienceDaily(PLoS ONE paper) Selected by R Jovani
How Birds of Different Feathers Flock Together ScienceDaily (Animal Behaviour paper) Selected by JL Alcantara
The Owl Comes Into Its Own The New York Times-Science Selected by JL Alcantara
On the evolution of UV vision in birds ScienceDaily(BMC Evol Biol paper) Selected by R Jovani
A great tit predating upon a common redpoll (video; Finnish) Ilta Sanomat Selected by R Jovani
Killing Barred Owls To Save the Spotted Owl CNN Selected by JL Alcantara
New dinosaur fossil challenges bird evolution theory e! Science News (Nature paper) Selected by JL Alcantara
Fractal geometry of a plumage pattern changes with physical condition in partridges ScienceNow(Proc R Soc B paper) Selected by I Galván
As Andean condors decline, tradition draws critics Reuters Selected by JL Alcantara





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Friday 5 December 2008

Per què els ous del ocells tenen taques?

Fins ara es pensava que les taques dels ous dels ocells només tenien funcions visuals, p.ex. per camuflar-los dels depredadors. Andrew G. Gosler i els seus col•laboradors han qüestionat aquesta idea estudiant els ous de les mallerengues carboneres (Parus major). Aquesta espècie fa niu en forats (foscos), i durant els dies de posta la femella tapa els ous amb material de niu. Per tant, possibles funcions estètiques de les taques perden tot el sentit. Per contra, les taques semblen estar relacionades amb el gruix de les closques, ja que van trobar-les en les zones més fines de l’ou, i eren més abundants en ous amb closques fines. A més, taques mes fosques indicaven zones especialment fines de la closca.

Aquestes taques estan formades per protoporfirines, que reflecteixen bé la llum infraroja i són semblants als lubricants sòlids utilitzats en enginyeria. Per tant, Gosler i el seu equip han arribat a la conclusió que les taques dels ous podrien reduir l’evaporació d’aigua i augmentar la duresa de les closques. D’aquesta manera, les taques servirien per pal•liar els problemes derivats de tenir una closa fina, característica comú entre els passeriformes.

> Gosler, A.G., Higham, J.P., & Reynolds, S.J. 2005. Why are birds’ eggs speckled? Ecology Letters 8: 1105-1113.
Photo by Soebe (Wikipedia Commons)

-------------------------- ESPAÑOL -------------------------

¿Por qué tienen manchas los huevos de los pájaros?

Hasta ahora, se pensaba que las manchas de los huevos de las aves sólo tenían funciones visuales, p.ej. para camuflarlos de los depredadores. Andrew G. Gosler y sus colaboradores han cuestionado esta idea estudiando los huevos de los carboneros comunes (Parus major). Esta especie hace nido en agujeros (oscuros), y durante los días de la puesta la hembra tapa los huevos con material de nido. Por lo tanto, posibles funciones de señalización de las manchas pierden todo su sentido. Por contra, las manchas parecen estar relacionadas con el espesor de los cascarones, ya que las manchas se encontraron en las zonas más finas del huevo, y eran más abundantes en huevos con cascarones finos. Además, manchas más oscuras indicaban zonas especialmente finas del cascarón.
Estas manchas están formadas por protoporfirinas, que reflejan bien la luz infrarroja y son parecidas a los lubricantes sólidos utilizados en ingeniería. Por lo tanto, Gosler y su equipo, han llegado a la conclusión que las manchas de los huevos podrían reducir la evaporación de agua y aumentar la dureza de los cascarones. De esta manera, las manchas servirían para paliar los problemas derivados de tener una cáscara fina, característica común entre los huevos de los paseriformes.

Foto de Soebe (Wikipedia Commons)

1 comment:

  1. I ♥ your entire blog. I am so glad to have found your contribution to avian-interest blogosphere!

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