New dinosaur discovered in New Mexico


Bistahieversor sealeyi skullFrom Science Centric in the USA:

New species of Tyrannosaur discovered in SW U.S

29 January 2010 16:56 GMT

New Mexico is known for amazing local cuisine, Aztec ruins and the Los Alamos National Laboratory. In the January issue of the Journal of Vertebrate Paleontology, palaeontologists Thomas Williamson of the New Mexico Museum of Natural History and Thomas Carr of Carthage College bring a new superstar to the state. Bistahieversor sealeyi is a brand new species of tyrannosaur discovered in the Bisti/De-na-zin Wilderness of New Mexico. Tyrannosaurs include the famous meat-eating dinosaur movie-stars like T. rex, and their characteristic body and skull shape (not to mention that mouthful of ferocious teeth!) make them easy for palaeontologists and kids to recognise. The skull and skeleton of Bistahieversor were collected in the first paleontological excavation from a federal wilderness area, and the specimen was airlifted from the badlands by a helicopter operated by the Air Wing of the New Mexico Army National Guard. ‘Bistahieversor sealeyi is the first valid new genus and species of tyrannosaur to be named from western North America in over 30 years,’ says Williamson.

Tyrannosaurs are best known from 65-75 million year old sediments from the Rocky Mountain region of North America. Bistahieversor provides important insights into the evolutionary history of the group. ‘Bistahieversor is important because it demonstrates that the deep snout and powerful jaws of advanced tyrannosaurs like T. rex were special adaptations that evolved around 110 million years ago, after the eastern and western halves of North America were separated by a shallow sea,’ says Carr. Bistahieversor was different from other tyrannosauroids in having an extra opening above its eye, a complex joint at its ‘forehead,’ and a keel along its lower jaw; it also had more teeth than its distant relative T. rex.

Bistahieversor skulls and skeletons collected from the Bisti/De-na-zin Wilderness and from the lands of the Navajo Nation are currently on display at the New Mexico Museum of Natural History.

See also here.

Hunting Dinosaurs With Jack Horner: here.

Pochard and more tufted ducks


This afternoon, again to the old harbour, where the weather was better than this morning.

Compared to yesterday, the mute swans were gone. The number of tufted ducks had risen from 3 to 5.

The mandarin ducks were near the other bank, but came over to join mallards, coots and moorhens when bread was thrown into the water.

On the banks, blue tit and redwing.

This is a redwing video.

And, where was the female common pochard of yesterday? Finally, as we were leaving, we discovered her. Swimming near the tufted ducks, and diving more often than them.

Beautiful bird photos: here.

Scottish barn owls die in winter weather


This is a barn owl video.

From the BBC:

Large number of dead barn owls found in Highlands

Large numbers of dead barn owls have been recorded by RSPB field workers in the north of Scotland.

The charity said it believed severe winter weather could have led to the birds starving to death.

Conservation worker Stuart Benn said deep snow had made it harder for the owls to catch food like mice and voles.

Finds along the coast of the Moray Firth suggested barn owls had flown from inland territories to hunt for the mammals.

Mr Benn said he found the remains of a barn owl close to the Norbord factory near Inverness Airport. Other deaths have also been reported to RSPB Scotland.

The conservation officer said: “It’s not just small birds that have suffered during the cold spell. We believe that a number of larger species have also suffered severely.

“Barn owls, in particular, seem to be doing badly.”

He added: “In recent years, due to a series of mild winters, the barn owl population had increased quite markedly in the north with the birds spreading into Sutherland.

“I suspect that progress has been put into sharp reverse by the weather.”

Woodcock and wood pigeons have also been affected.

Barn owl nestbox in Goeree: here.

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New dinosaur, and bird evolution


From the BBC:

New dinosaur discovery solves evolutionary bird puzzle

By Doreen Walton
Science reporter, BBC News

A newly discovered fossil has shed light on why a group of dinosaurs looks like birds, say scientists.

Haplocheirus sollers may not be as charismatic as T. rex or as agile as a pterodactyl but it’s thought to solve a long standing puzzle.

Researchers believe its short arms and large claw show how bird-like dinosaurs evolved independently of birds.

The 3m-long skeleton, found on an expedition to China’s Gobi desert, is described in the journal Science.

The fossil is a member of the Alvarezsauridae family, a group of bird-like dinosaurs. The group shares features with birds, including fused wrist elements and a loosely structured skull.

But the researchers say the new fossil shows the Alvarezsauridae group split from birds much earlier on the evolutionary tree than was thought.

“Haplocheirus is a transitional fossil,” Jonah Choiniere from George Washington University told the BBC.

“Previously we thought the Alvarezsauridae were primitive, flightless birds. This discovery shows they’re not and that the similarities between them evolved in parallel.”

The fossil is of a nearly complete adolescent dinosaur skeleton and was found in orange mudstone beds in the Junggar Basin, Xinjiang, China.

It was spotted when a member of the team noticed the pelvis at the ground’s surface. The rest of the skeleton was found only inches down.

The new dinosaur shows an early evolutionary step in the development of the short, powerful arm typical to the Alvarezsauridae group.

“The rest of the members of this group have really short forelimbs with huge muscle attachments, like body-builder arms. The fossil shows the first step in the evolution of this weird arm and claw,” said Mr Choiniere.

Varied diet

The researchers believe the fossil shows development of the two diverged in the Late Jurassic period, about 160 million years ago. Until now there was no evidence of this type of dinosaur living at that time.

“It’s like finding a great, great grandfather in your family which doubles the age of your family tree,” said Mr Choiniere.

Scientists believe that birds descended from theropods or bird footed dinosaurs in the Late Jurassic. Theropods include alvarezsaurs, other bird-like dinosaurs including the well known Velociraptor, meat eaters like T. rex and modern birds.

Haplocheirus sollers means simple, skillful hand. The fossil shows the dinosaur had small teeth and researchers believe the claw may have been used for digging termites.

“It may have had a very general diet, tackling smaller animals like lizards, very small mammals and very small crocodile relatives,” explained Mr Choiniere. “It was a lightly built animal and could run very quickly.”

If, as the old proverb goes, a bird in the hand is worth two in the bush, it’s because most of today’s birds can swiftly fly away before you can catch them. But that hasn’t always been true: The first birds were not impressive flyers, according to a new study of fossil bird feathers. Some researchers, though, say it’s too soon to clip the wings of our earliest feathered friends: here.

ScienceDaily (May 26, 2010) — The evolution of flight took longer than previously thought with the ancestors of modern birds “rubbish” at flying, if they flew at all, according to scientists: here.

If birds descended from dinosaurs, why are they warm-blooded? Here.

Great grey shrike in the Netherlands


This is a great grey shrike video from Britain.

And this is the sequel.

Yesterday night in Hilversum, there were lectures about local birds. And about birds in Mount Hagen and elsewhere in Papua New Guinea.

And, by Paul van der Poel, about the great grey shrike; especially in the Tafelberg heath reserve, between Huizen and Laren, not far from Hilversum.

Great grey shrikes used to breed in heathland in the Netherlands. Unfortunately, they have become extinct as breeding birds. However, East European migrants still arrive every autumn to winter; including at the Tafelberg reserve. They are songbirds, but have a lifestyle reminiscent of birds of prey. However, they do not have bird of prey talons, so like other shrikes, they often impale their prey on thorns.

What do great grey shrikes eat?

They arrive at Tafelberg in October, last year in the 12-13 October night. Their staple food then are minotaur beetles. However, as it gets colder and there may be snow, these beetles and other large insects, like dragonflies and buff-tailed bumblebees, eaten by shrikes as well, will tend to hide (though they may come out on warmer days in winter). The shrikes then will have to find other sources of food.

About the same as for beetles goes for lizards. As far as we know, the only lizard species at Tafelberg is the common lizard; very probably no sand lizards. The common lizards also tend to hide as winter comes.

Mice and shrews are still present in winter. Among the prey species of Tafelberg shrikes are field vole, bank vole, Eurasian pygmy shrew, and common shrew. However, if after snow mice go underground, great grey shrikes will have to eat birds.

They can catch birds up to the size of a redwing. Among the species they catch at Tafelberg are chaffinch, brambling, meadow pipit, robin, short-toed treecreeper, skylark, wren, great tit and long-tailed tit.

Great grey shrike predation of common lizards at Tafelberg: here. And here.

Great grey shrikes in Libya: here.

With climate change, birds are taking off for migration sooner; not reaching destinations earlier: here.