This is a sweet little video about the Sanderlings that nested on the Niederlande beach of Schiermonnikoog. However, in just a few short years, they are rarely seen there. Why? This video provides some hypotheses.
Archive for the 'Ornithology' category
tags: evolution, evolutionary biology, gynandromorph, bilateral gynandromorph bird, half-sider, mixed-sex chimaera, sex determination, molecular biology, genetics, developmental biology, endocrinology, birds, chicken, Gallus gallus, ornithology, bpr3.org/?p=52,peer-reviewed research, peer-reviewed paper, journal club
Almost exactly one year ago, hundreds of American birders
were thrilled by sightings and photographs of this remarkable
Northern Cardinal, or Redbird, Cardinalis cardinalis,
photographed in Warrenton, VA.
Image: DW Maiden, 2 March 2009.
I'll never forget the first time I saw a bilateral gynandromorph. I was a bird-crazy teenager reading my way through a stack of avicultural publications when I spied the strangest bird I'd ever seen on the cover of one magazine: an eclectus parrot that was very precisely divided down the middle: one side was rich scarlet and the other was brilliant emerald. Because eclectus parrots are sexually dimorphic -- females are red and males are green -- this remarkable bird was easily identifiable as being composed of both sexes, one on each side.
Even though this was the first time I'd ever seen a gynandromorph, these mysterious birds do pop up from time to time. For example, bird watchers occasionally run across them in the wild (see above photograph) and poultry farmers sometimes find them in their flocks: it is estimated that roughly one in 10,000 domestic chickens -- another sexually dimorphic species -- is a gynandromorph.
tags: evolution, evolutionary biology, ancient DNA, aDNA, molecular biology, molecular ecology, archaeology, paleontology, fossil eggshell, extinct birds, giant moa, Dinornis robustus, elephant birds, Aepyornis maximus, Mullerornis, Thunderbirds, Genyornis, bpr3.org/?p=52,peer-reviewed research, peer-reviewed paper, journal club
Elephant bird, Aepyornis maximus, egg
compared to a human hand with a hummingbird egg balanced on a fingertip.
To conduct my avian research, I've isolated and sequenced DNA from a variety of specimens, such as blood, muscle, skin and a variety of internal organs, dry toepads from long-dead birds in museum collections, feathers, the delicate membranes that line the inside of eggs, and even occasionally from bone. But I was surprised to learn that avian DNA can also be extracted directly from fossilized eggshells -- eggshells that completely lack eggshell membranes.
tags: faith-based birding, mass hysteria, endangered species, extinct species, conservation, politics, Ivory-billed Woodpecker, Campephilus principalis, IBWO, ornithology, birds, bpr3.org/?p=52,peer-reviewed research, peer-reviewed paper
The Cornell Lab of Ornithology has posted a reward of $50,000
to be given to anyone who can provide "video, photographic, or
other compelling information and lead a project scientist to a
living wild Ivory-billed Woodpecker."
Mass hysteria is that strange psychological phenomenon where a group of people experience the same hallucination at the same time. Such hallucinations include observing statues or paintings of the Virgin Mary either bleeding or crying at certain times of the year. But mass hysteria is not limited to religious fanatics. During the past five years, there has been a marked increase in what I refer to as "faith-based birding," where groups of people believe they've seen the Ivory-billed Woodpecker, Campephilus principalis, a large bird that has been extinct in the US for more than 50 years.
tags: evolutionary biology, paleontology, taphonomy, plumage color, feathers, color, melanin, eumelanin, phaeomelanin, dinosaurs, theropod, paravian, avialae, fossils, Anchiornis huxleyi, ornithology, birds, bpr3.org/?p=52,peer-reviewed research, peer-reviewed paper
New research reveals that recently-described 155-million-year-old
Anchiornis huxleyi, a woodpecker-like dinosaur the size of
a modern-day domesticated chicken, had black-and-white spangled wings and a rusty red crown.
Fig. 4. Reconstruction of the plumage color of the Jurassic troodontid Anchiornis huxleyi. The tail is unknown specimen BMNHC PH828, and reconstructed based on the complete specimen previously described. Color plate by Michael A. Digiorgio.
Ever since dinosaurs were discovered, scientists, artists and children everywhere have speculated about what they really looked like. Fossilized bones, skin impressions and recently, feathers, provide a general mental image of these animals' appearances, but these materials also leave important questions unanswered, basic questions such as what color were dinosaurs?
tags: evolutionary biology, convergent evolution, paleontology, taxonomy, zoology, basal birds, theropods, dinosaurs, ornithology, birds, Alvarezsauroidea, Haplocheirus sollers, Maniraptora, Archaeopteryx, bpr3.org/?p=52,peer-reviewed research, peer-reviewed paper
A Newly Discovered Basal Alvarezsauroid Theropod from the Early Late Jurassic.
Artwork: Portia Sloan [larger view]
A long-standing scientific debate focuses on the origins of birds: did they evolve from reptiles or dinosaurs? Currently, most scientists think that birds are modern dinosaurs, but because small hollow bones like those of birds and small dinosaurs don't fossilize well, the early fossil record for birds is sparse. However, a new dinosaur species unearthed in China's Gobi Desert strengthens the dinosaur-bird hypothesis and may also provide valuable clues as to how flight evolved.
tags: evolutionary biology, fossils, feathers, plumage color, color, dinosaurs, theropods, Sinosauropteryx, Sinornithosaurus, birds, Confuciusornis, melanosomes, phaeomelanosomes, eumelanosomes, keratinocytes, SEM, scanning electron microscopy, 10.1038/nature08740, bpr3.org/?p=52, peer-reviewed research, peer-reviewed paper
Reconstruction of two Sinosauropteryx, sporting their orange and white striped tails.
Artwork by Chuang Zhao and Lida Xing [larger view]
While looking at museum dioramas that feature dinosaurs, I often overhear people asking "How do they know what color dinosaurs were?" The truth is that artists and scientists didn't know -- until now. A new paper was just published in Nature that carefully examines fossilized plumage and comes to an interesting conclusion: scientists can identify at least some of the original colors in ancient feathers.
tags: evolution, evolutionary biology, evolutionary ecology, plumage color,carotenoid-based colour, carotenoids, lipid peroxidation, oxidative stress, sperm motility, sperm quality, sperm velocity, birds, ornithology, Great Tit, Parus major, bpr3.org/?p=52,peer-reviewed research, peer-reviewed paper
Great Tit, Parus major.
Image: Luc Viatour, Creative Commons/Wikipedia [larger view]
In some species of birds, males are more brightly colored than females. This phenomenon is due to female choice: females choose to mate with males that have the brightest plumage colors and most elaborate ornaments. But these characters are more than mere glitzy advertising, they are an example of honest signals because the brightest plumage and most elaborate ornaments are worn only by those males who have managed to procure enough resources necessary to grow them. But what is the link between plumage brightness and male quality? According to a newly published study of Great Tits, Parus major, males with more intensely colored breast plumage produce faster and more motile sperm.
tags: evolutionary biology, behavioral ecology, migration, microtechnology, geolocator, natural history, biological hotspots, longest migration, seabirds, Arctic Tern, Sterna paradisaea, bpr3.org/?p=52,peer-reviewed research, peer-reviewed paper
Arctic Tern, Sterna paradisaea, Iceland.
Image: Arthur Morris, Birds as Art, 2007 [larger view].
Canon 400mm f/5.6L lens (handheld) with the EOS-1D Mark III. ISO 200. Evaluative metering +1/3 stop: 1/1000 sec. at f/5.6 in Manual mode. Manual Flash with Better Beamer at 1:1.
For decades, it was widely suspected that a small seabird, the Arctic Tern, Sterna paradisaea, migrates an estimated 40,000 km each year -- the longest migratory journey of any animal.
"This is a mind-boggling achievement for a bird of just over 100 grams," says Carsten Egevang, a seabird researcher with the Greenland Institute of Natural Resources.