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The oldest known bird fossils from New Zealand were recently unearthed along a remote stretch of beach on the Chatham Islands, researchers announced.
The fossils represent possibly four new species of seabirds dating back to the late Cretaceous period, around 65 million years ago.

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Did modern birds originate around the time of the dinosaurs' demise, or have they been around far longer?
The question is at the centre of a sometimes contentious "rocks versus clocks" debate between palaeontologists, whose estimates are based on the fossil record, and scientists who use "molecular clock" methods to study evolutionary history.
A new analysis by researchers at the University of Michigan, the University of Chicago, the Centre for Biodiversity Conservation Mexico and Central America, and Boston University offers the strongest molecular evidence yet for an ancient origin of modern birds, suggesting that they arose more than 100 million years ago, not 60 million years ago, as fossils suggest.
The research was published online Jan. 28 in the journal BMC Biology.

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Scientists believe they could be a step closer to solving the mystery of how the first birds took to the air.
A study published in the journal Nature suggests that the key to understanding the evolution of bird flight is the angle at which a bird flaps its wings.
The US team found that birds move their wings at the same narrow angle, whether they run, fly or glide.
They conclude that early birds may have begun to fly by simply learning to flutter their wings at the right angle.

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Extinct sea bird once again caught in the Hauraki Gulf
The once presumed extinct New Zealand storm petrel has again been recently captured in the Hauraki Gulf but its breeding site remains a mystery.
A team including Department of Conservation staff and scientists, funded jointly by DOC and a grant from National Geographics Committee for Research and Exploration, caught three birds during October and early November this year. This brings the tally to seven birds captured since the petrel was rediscovered by Dr Stephenson and Sav Saville of the coast of Whitianga in January 2003.

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Bird song
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A 200,000 study into what happens when people hear birdsong is taking off.
Researchers at Aberdeen University will spend two years listening to birds to find out how their songs, calls and cries become a part of people's lives.

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Anyone who wants to submit details of a bird sound experience can do so on the project website - www.abdn.ac.uk/birdsong/

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Mesozoic birds
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The origin and early evolution of birds has been a major topic in evolutionary biology. In the 20th century, evolutionary scenarios posited either a ground-based bird ancestor or an arboreal ancestor.
By comparing the claw curvatures of ancient and modern birds, researchers provide new evidence that the evolutionary ancestors of birds primarily made their livings on the ground rather than in trees.

The claws of Mesozoic birds and their immediate ancestors, the non-avian theropods, are relatively straightmost like of birds that are now either specialised for walking on the ground or have a preference for it, rather than the highly curved claws of birds that spend a lot of time in trees. We were particularly surprised by the fact that all the fossil species, representing evolutionary lineages from non-flying ancestors to early flying birds, had claws more like modern birds that spend most of their time on the ground - Christopher Glen of the University of Queensland.

The new study suggests that part of the problem is the loose categorisation of many living bird species as either ground- or tree-dwellers on the basis of their hind limbs when, in reality, these are not mutually exclusive alternatives. Rather, birds exhibit differing degrees of ground- and tree-based behaviours and would be better placed along a continuum according to the proportion of time spent on ground versus tree foraging.
To test the idea, Glens group first analysed the toe claws of 249 species of recent birds, revealing that their claw curvatures increase, becoming more hooked, as tree foraging becomes more predominant. They then compared the claw curvatures of modern birds to those of the fossilised ancestors of birds.

In summary, since claw angle is independent of body size and the evolutionary relationships among species, it is a reliable indicator of the predominant behaviour reliant upon hind-limb locomotion, and can make an important contribution to reconstructing the ecomorphology of fossil specieshow they lived and used their environments. Our findings suggest early birds foraged predominantly on the ground, rather than supporting previous suggestions of arboreal claw adaptations, which appear to have evolved later in the lineage.

Source Cell Press (subscription)

-- Edited by Blobrana at 00:35, 2007-11-06

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Incidents of a seabird preying on colonies of another species at night may be unique to a remote islands archipelago.
Ecologist Will Miles said initial research of great skua preying on Leach's petrel on St Kilda found the behaviour was unlikely to be common.

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Chinese crested tern
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The Chinese crested tern, a rare sea bird whose eggs are prized by some as a delicacy, is likely to be extinct in five years if authorities do not step up protection efforts, a conservation group said Friday.
The bird looks set to be the latest ecological victim of China's rapid 30-year economic expansion and industrialisation, which has raised the standard of living for hundreds of millions of Chinese but ravaged the environment. Late last year, scientists declared that a rare Chinese river dolphin was effectively extinct after conducting a fruitless six-week search for the creature in its Yangtze River habitat.

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Birds
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It's official - the godwit makes the longest non-stop migratory flight in the world.
A bird has been tracked from its Southern Hemisphere summertime home in New Zealand to its breeding ground in Alaska - and back again.
The bar-tailed godwit, a female known as E7, landed in New Zealand this past weekend after taking a week to fly 11,500km from Alaska to New Zealand.

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