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2009-07-12 – Australia: World’s Oldest Dinosaur Burrow


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World’s Oldest Dinosaur Burrow Discovered In Australia

Posted on: Friday, 10 July 2009, 16:20 CDT | Related Video

Paleontologists have discovered the world’s oldest dinosaur burrows in Australia.  The 106-million-year-old burrows are the first to be found outside of North America, and were much closer to the South Pole when they were created.

In total, three separate burrows have been discovered, the largest of which was about 6ft. long.  Each burrow had a similar design and was just large enough to contain the body of a small dinosaur.

The discovery supports the theory that dinosaurs living in harsh, cold climates burrowed underground to survive.

The only other known dinosaur burrow was discovered in 2005 in Montana, and contained the bones of an adult and two young dinosaurs of a small new species called Oryctodromeus cubicularis. Two years after its discovery, scientists dated the burrow from 95 million years ago.   

The older burrows in Australia were found by one of the researchers who made the original Montana discovery.

“Like many discoveries in paleontology, it happened by a combination of serendipity and previous knowledge,” said Anthony Martin of Emory University in Atlanta.

“In May 2006, I hiked into the field site with a group of graduate students with the intention of looking for dinosaur tracks. We did indeed find a few dinosaur tracks that day, but while there I also noted a few intriguing structures,” he told BBC News.

Martin returned to the site, known as Knowledge Creek about 150 miles from Melbourne, to study the structures in July 2007 and again in May of 2009.

He was astonished at what he found.

“I was scanning the outcrop for trace fossils, and was very surprised to see the same type of structure I had seen in Cretaceous rocks of Montana the previous year,” said Martin.

That original structure was the burrow of O. cubicularis.

“So to walk up to the outcrop and see such a strikingly similar structure, in rocks only slightly older, but in another hemisphere, was rather eerie,” Martin said.

Within the rock, which is part of the Otway group of rocks that have produced a large diversity of vertebrate fossils, Martin discovered three separate burrows less than 10 feet apart, two of which formed a semi-helix twisting down into the rock.

The largest and best-preserved burrow turns twice before ending in a larger chamber. Dubbed tunnel A, it is more than 6 feet in length. Martin calculates that an animal weighing around 22 pounds would have created each burrow. Twisting burrows can help keep predators at bay and provide a steady temperature and humidity environment.

Alligators, aardwolves, coyotes, gopher tortoises and striped hyenas are among the modern animals that make such burrows.

Although Martin isn’t sure which species of dinosaur made the burrows, he noted how similar their designs are to the burrow created by O. cubicularis.

A number of small ornithopod dinosaurs, which stood upright on their hind legs and were about the size of a large iguana, were believed to have lived in the area during the same time in the Cretaceous period.

Martin has ruled out a number of other sources that could have created the burrows.

The fact dinosaurs created them makes sense, he said.

Australian researchers first proposed two decades ago that some dinosaurs might have created burrows to survive harsh climates they couldn’t escape from by migrating.

“It gives us yet another example of how dinosaurs evolved certain adaptive behaviors in accordance with their ecosystems,” Martin said.

“Polar dinosaurs in particular must have possessed special adaptations to deal with polar winters, and one of their behavioral options was burrowing. It provides an alternative explanation for how small dinosaurs might have overwintered in polar environments.”

Martin hopes that paleontologists will be on the look out for dinosaur burrows, and for dinosaurs that are physically adapted to burrowing into soil.

The findings were published in the journal Cretaceous Research.

Image 1: Drawing by James Hays, Fernbank Museum

Image 2: Following his Montana discovery of the first trace fossil of a dinosaur burrow, Emory University paleontologist Anthony Martin has found evidence of older, polar dinosaur burrows in Victoria, Australia.

On the Net:

Source: redOrbit Staff & Wire Reports

luglio 12, 2009 Posted by | - R. Dinosauri, 1 Cretaceo, An. Vertebrates, Mesozoic, Oceania, P - Impronte, P - Ritrovamenti fossili, Paleontology / Paleontologia | , , , | Lascia un commento

2008-11-23 – Australia: “collezione nazionale” (nation’s fossil collection)

Un gruppo di volontari in Australia sta organizzando la più grossa collezione di ossa i dinosauri dell’Australia ….

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Group prepares nation’s largest dinosaur fossil collection

Posted Sat Nov 22, 2008 1:23pm AEDT

An outback Queensland group is preparing the largest collection of dinosaur-age fossils ever gathered in Australia.

The Australian Age of Dinosaurs at Winton in the central west says it is employing two workers and over the past two years scores of volunteers have been helping to prepare fossils at its dinosaur laboratory.

The group is proposing a multi-million dollar dinosaur and natural history museum to showcase the finds.

Spokesman David Elliott says the massive collection is only the tip of the iceberg because the region is rich with ancient bones.

“We’ve got new species of dinosaurs and they are studying those now,” he said.

“Of course one day – it’s not all that long away – we will be able to release those animals and we’ll know exactly what they are and what their relevance is to other dinosaurs around the world.

“This is going to be big news not just for western Queensland, but for Australia.”

http://www.abc.net.au/news/stories/2008/11/22/2427059.htm?section=justin

novembre 23, 2008 Posted by | - R. Dinosauri, Italiano (riassunto), Oceania, Paleontology / Paleontologia | , , , , | Lascia un commento

2008-10-22 – Nuove ipotesi su migrazione dei Dinosauri polari (Polar dinosaurs, migration)

Uno studio condotto con un approccio di tipo fisiologio (ad es. energia necessaria) ha evidenziato che non tutti i dinosauri erano in grado di sostenere lunghe migrazioni da e verso i poli, ritenendo dunque plausibile che essi fossero invece adattati alla vita e al clima alle basse latitudini.

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Polar dinosaurs may have taken shorter treks

Phil Bell holding a vertebra of a 70-million-year-old Saurolophus.

October 21, 2008 – Edmonton-Contrary to popular belief, polar dinosaurs may not have traveled nearly as far as originally thought when making their bi-annual migration.

University of Alberta researchers Phil Bell and Eric Snively have suggested that while some dinosaurs may have migrated during the winter season, their range was significantly less than previously thought, which means their treks were shorter. Bell and Snively’s findings were recently published in Alcheringa: An Australasian Journal of Paleontology.

The idea that these animals may have travelled distances nine times further than mule deer or four times those of wildebeest would have made them the greatest migrators in history. “There are strong opinions regarding dinosaur migration, but we decided to take a different approach, looking at variables such as energy requirements,” said Bell. Their research led them to suggest that migrating dinosaurs could have travelled up to 3,000 kilometres in a round trip-lasting perhaps up to six months-half of the distance suggested previously.

According to Bell, the notion of migrating polar dinosaurs is not new; however, previously-held beliefs were that the animals followed the centrally shifting sunlight, or latitudinal “sun line,” as part of their migration and would travel as far as 30 degrees of latitude, or 3,200 kilometres, in order to survive. Given their size and physiology, Bell and Snively have concluded that dinosaurs would have been incapable of sustaining the effort needed to make the trip. “When we looked at the energy requirements needed to support a three-tonne Edmontosaurus over this distance, we found it would have to be as energy efficient as a bird. No land animal travels that far today,” said Bell.

Bell does not dispute the evidence of migration and points to discoveries of large bone beds as evidence that many dinosaurs also traveled. In order to sustain the herd, “it seemed to make sense that they would be moving to and from the poles,” he said.

While this view of migration is feasible for some species of polar dinosaurs, it does not hold for all, Bell noted. “Many types of dinosaurs were surviving in polar latitudes at the time, and getting along quite fine,” said Bell. “They were not physically able to remove themselves from the environment for a variety of reasons and had to adapt to the cold, dark winters just as the rest of us mammals do today.”

 Related Internal Links

University of Alberta Department of Biological Sciences:
http://www.biology.ualberta.ca/

source: http://www.expressnews.ualberta.ca/article.cfm?id=9693
Other links: http://www.sciencedaily.com/releases/2008/10/081021185205.htm
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original article:
Alcheringa: An Australasian Journal of Palaeontology, Volume 32 Issue 3 2008 271 – 284
Authors: Phil R. Bell; Eric Snively
DOI: 10.1080/03115510802096101

Abstract

Cretaceous polar dinosaur faunas were taxonomically diverse, which suggests varied strategies for coping with the climatic stress of high latitudes. Some polar dinosaurs, particularly larger taxa such as the duckbill Edmontosaurus Lambe, 1917, were biomechanically and energetically capable of migrating over long distances, up to 2600 km. However, current evidence strongly suggests many polar dinosaurs (including sauropods, large and small theropods, and ankylosaurs of New Zealand) overwintered in preference to migration. Certain groups also appear more predisposed to overwintering based on their physical inability (related to biomechanics, natural history, or absolute size) to migrate, such as ankylosaurs and many small taxa, including hypsilophodontids and troodontids. Low-nutrient subsistence is found to be the best overwintering method overall, although the likelihood that other taxa employed alternative means remains plausible. Despite wide distribution of some genera, species-level identification is required to assess the applicability of such distributions to migration distances. Presently, such resolution is not available or contradicts the migration hypothesis.
Keywords: Alaska; Albian; Aptian; Australia; Campanian; Cretaceous; Dinosaur Cove; endothermy; migration; New Zealand; polar dinosaurs

ottobre 22, 2008 Posted by | - R. Dinosauri, 1 Cretaceo, America Northern, Antartide, Articolo sc. di riferimento, Oceania, P - Paleoetologia, Paleontology / Paleontologia | , , , , , , , , , , , | Lascia un commento

2008-10-16 – Melbourne, Australia: Nel museo nuova sala per i dinosauri (Museum,Dinosaur Walk)

Nel museo di Melbourne si inizia a preparare la nuova sala he ospiterà le collezioni di geologia, paleontologia e zoologia.

Sono stati investiti 7 milioni di dollari australiani e la “Dinosaur Walk” sarà pronta nell Aprile 2009.

Intanto si comincia a smontare gli scheletri ………………

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Museum no architectural dinosaur

THE dinosaurs will soon walk again, and they will do so in Melbourne.

October 15, 2008 12:00am

 

Melinda Iser/Museum Victoria

Museum staff dismantle a Mamenchiasaurus dinosaur in preparation for upcoming exhibition Dinosaur Walk, opening April 2009. Picture: Melinda Iser/Museum Victoria

Melbourne Museum is about to embark on a $7 million refurbishment that will include a dinosaur walk exhibit and room for more than 3000 never-before-seen objects from the Museum’s collection.

The new Science and Life Gallery will cover palaeontology, geology, bird and mammal collections.
The Dinosaur Walk is due to open in April next year, and will be followed by an exhibit on Victoria’s biodiversity, one presenting 600 million years of evolution, and the final display will address the Earth’s formation.

Museum Victoria CEO Dr Patrick Greene said the work is an enormous undertaking.

“This is the largest gallery redevelopment ever planned by Museum Victoria. When completed, the Science and Life Gallery will be one of the most comprehensive natural sciences galleries in Australia,” Dr Greene said.

The Museum’s head of sciences Dr John Long said the new exhibits will contribute to the public’s knowledge of the natural world.

“The diverse displays in the galleries will be united by one theme – change: changing climates, changing landscapes, changing life forms – which will tell the story of evolution,” he said.

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Links:

ottobre 16, 2008 Posted by | - R. Dinosauri, Italiano (riassunto), Multimedia, Musei, Oceania, Paleontology / Paleontologia | , , , , , , | Lascia un commento

2008-09-22 – Scogliera fossile scoperta in Australia

Fossil reef found in Aussie outback


 

Estee Woon)</EM>

Photo: Jonathan Giddings stands next to the 650-million-year-old fossilised layers found in the Northern Flinders Ranges (Source: Estee Woon)

Australian scientists have discovered an ancient reef that may push back the evolution of the earliest animals by 80 million years.

The unpublished research, by geoscientists Associate Professor Malcolm Wallace, Estee Woon and Jonathan Giddings from the University of Melbourne, will be presented at the Selwyn Symposium on Thursday.

The researchers say they have uncovered complex organisms that in some ways resemble multicellular life in a large reef located in the Northern Flinders Ranges, 700 kilometres north of Adelaide in South Australia.

If the fossils, which are around 650 million years old, are of multicellular organisms, they would be the earliest examples of primitive animal life discovered so far, the researchers say.

The fossils are yet to be described scientifically, but look like cauliflowers and were probably sponge-like organisms up to two centimetres in diameter, Wallace says.

‘Nothing else like them’

He says the reef-building organisms were “certainly more complex than any fossil of their age anywhere on Earth”.

“They’ve never been described from anywhere else in the world.

There’s nothing else like them,” says Wallace.

The ancient reef, which is now exposed on the surface, was 10 times higher than the Great Barrier Reef, and consisted partly of stromatolites, layered structures built by microbes, and partly of the sponge-like organisms.

The find is especially significant because it may be the missing piece of the puzzle in the evolution of early animal life.

Before the Ediacaran geological period, 635 million years ago, the only life forms were simple, single-celled organisms.

Then suddenly, 570 million years ago, very complex animals appear in the fossil record.

Scientists have long debated just what caused this evolutionary explosion in life.

“When you see the Ediacara they resemble jellyfish and modern arthropods [the group that contains insects and spiders],” Wallace says.

“There is no doubt they are animals. The real puzzle is why they appeared 570 to 540 million years ago.

“Maybe this reef system will tell us something about that.”

‘Extremely important’

Dr Jim Gehling, a palaeontologist from the South Australian Museum in Adelaide, says if verified the find will be “extremely important” and “very exciting”.

“We know these things [the Ediacara] must have had ancestors; when they occurred is the great debate,” Gehling says.

He says the find would confirm predictions based on the molecular record that pinpoint evolutionary steps based on the rates of DNA mutation.

Most branching of the molecular tree occurred in the Ediacaran when there was an evolutionary explosion in life.

But according to the molecular record, sponges should have branched off 650 to 680 million years ago, which is about when these reefs occur, Gehling says.

“If he’s found evidence of sponges, and that would need to be verified, that’s exactly what the molecular records predict and that would be very exciting,” he says.

The Selwyn symposium will have international and Australian scientists debating theories on what led to the “evolutionary explosion” of life at the time of the first animals.

Tags: oceans-and-reefs, earth-sciences, palaeontology

http://www.abc.net.au/science/articles/2008/09/22/2370844.htm?site=science&topic=latest

 

settembre 22, 2008 Posted by | Geology - Geologia, Oceania, P - Ritrovamenti fossili, Paleontology / Paleontologia | , , , , , | 1 commento

2008-09-16 Probabile nuovo dinosauro scoperto in Australia

Dig uncovers new dinosaur bones

September 16, 2008 12:44pm

Article from: AAP

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A DIG for dinosaur bones in western Queensland may have uncovered a new species, scientists say.

The Australian Age of Dinosaurs Institute has completed a two-week dig at a remote sheep and cattle station near Winton, where a 20-metre sauropod, dubbed Matilda, was discovered three years ago.

Institute chairman David Elliott said the fossils found in the latest dig were up to 98 million years old.

“We took back two ute fulls of bones,” Mr Elliott said.

“Because they’re small bones we don’t think they belong to Matilda.

“We’re hopeful it’s something totally unique but we won’t know anything until six to eight months’ time.”

Mr Elliott said more of Matilda’s bones were also retrieved.

“We’re looking at one of the biggest concentrations of dinosaur bones that we’ve ever found,” he said.

“There’s a huge potential for some very exciting discoveries to come out of this work.”

Sauropods, which first appeared in the late Triassic Period, were the largest animals to have lived on land.

http://www.news.com.au/story/0,23599,24354376-29277,00.html
Hopes that Australian dinosaur find is new species
AFP – 16 set 2008
SYDNEY (AFP) — Australian scientists were hopeful Tuesday that two tonnes of bones found in the country’s northeast are the remains of a new species of
‘Huge potential’ in outback dinosaur find
ABC Online – 15 set 2008
Scientists say it is too early to speculate on a new discovery of dinosaur bones in western Queensland, but it is a significant find.

settembre 20, 2008 Posted by | - R. Dinosauri, Oceania, P - Ritrovamenti fossili, Paleontology / Paleontologia | , , | Lascia un commento

Nuove ossa di dinosauro dissotterrate in Australia

Articolo tratto da www.abc.net.au (link):

Metre-long bones found in dinosaur dig

A two-week dinosaur dig in south-west Queensland has unearthed more of Australia’s largest dinosaur, Cooper.

The Mackenzie family first found dinosaur bones on their Eromanga property, Plevna Downs, when they were mustering a few years ago.

Stuart Mackenzie says this is the second dig they’ve held, and he says they’ve uncovered bones that are more than a metre long.

“Just that day to day getting up and never knowing what you’re going to find that day,” he says.

“I suppose opal miners go through it as well, it’s just that thrill of discovery and you never know what you are going to find and if in fact you are going to find anything at all.

“But everytime you hit something, it’s pretty exciting stuff.”

giugno 9, 2008 Posted by | - R. Dinosauri, Oceania, P - Ritrovamenti fossili, Paleontology / Paleontologia | , | Lascia un commento

Studi genetici su un marsupiale estinto – Thylacinus cynocephalus

Articolo tratto da Le Scienze:
La tigre della Tasmania

‘Resuscitati’ geni di un marsupiale estinto

La ricerca ha un potenziale enorme, dallo sviluppo di nuove biomedicine alla comprensione della biologia degli animali estinti

Alcuni geni del tilacino (Thylacinus cynocephalus) – un marsupiale estinto noto anche come lupo o tigre della Tasmania – sono stati estratti da un esemplare conservato presso il Museo Victoria di Melbourne e trasferiti in un topo per osservarne le funzioni biologiche. “Questa è la prima volta che il DNA di una specie estinta viene utilizzato per indurre una risposta funzionale in un organismo vivente” ha osservato Andrew Pask, dell’Università di Melbourne, che con Richard Behringer. dell’Università del Texas, ha diretto la ricerca.

L’ultimo esemplare di questo predatore marsupiale carnivoro morì nel 1936 nello zoo di Hobart, dopo anni anni di caccia che avevano già condotto alla scomparsa degli esemplari selvatici agli inizi del Novecento.

In diversi musei del mondo alcuni esemplari di tilacino sono stati però conservati sotto alcol e questo ha permesso una conservazione dei tessuti sufficientemente buona per estrarre da alcuni piccoli campioni il DNA necessario allo studio.

Il gene “resuscitato” e inserito in un embrione di topo al posto di quello naturale ha dimostrato di essere perfettamente funzionale. In particolare i riceratori – che descrivono il loro studio in un articolo pubblicato sulla rivista ad accesso pubblico PLoS ONE – hanno dimostrato che il gene Col2a1 di tilacino ha la stessa funzione – quella di sviluppare ossa e cartilagini – che ha il suo analogo naturale nel topo.

“Via via che le specie di estinguono, perdiamo sempre più conoscenze critiche sulle funzioni dei geni e sulle loro potenzialità”, ha spiegato Pask. “Finora siamo stati in grado solo di leggere le sequenze geniche di specie estinte. Questa ricerca è stata sviluppata per fare un passo in più: esaminare la funzione di un gene in un organismo nella sua interezza.”

“La ricerca ha un potenziale enorme, dallo sviluppo di nuove biomedicine alla comprensione della biologia degli animali estinti”, ha aggiunto Behringer. “Grazie al nostro metodo, anche per le specie che sono già estinte l’accesso alla loro biodiversità può non essere del tutto perduto”, ha concluso Marilyn Renfree, che ha partecipato alla ricerca. (gg)

maggio 31, 2008 Posted by | - Marsupiali, FREE ACCESS, Genetic / Genetica, Oceania, Paleontology / Paleontologia | , , , , , , | Lascia un commento

Più antico resto fossile di maternità – Materpiscis attenboroughi

Straordinaria scoperta fossile in Australia, ritrovato infatti un reperto fossile testimoniante un parto in un esemplare di pesce placoderma attribuito al genere: Materpiscis attenboroughi

Articolo da Agi news:

SCIENZA: LA NASCITA PIU’ ANTICA IN FOSSILE DI 380 MILIONI ANNI

(AGI/AFP) – Parigi, 28 mag. –  In Australia e’ stata scoperta traccia della piu’ antica maternita’ mai documentata: un fossile di pesce di 380 milioni di anni, fa con attaccato al cordone ombelicale un minuscolo embrione. Il ritrovamento del “Materpiscis attenboroughi”, come e’ stato ribattezzato il fossile della “madre-pesce” in onore del naturalista David Attenborough, e’ opera di John Long e Kate Trinajstic del museo di Victoria.
  Oltre a portare alla luce una specie animale finora sconosciuta, il fossile e’ la piu’ antica testimonianza di una nascita nel regno animale. “E’ uno piu’ straordinari reperti fossili mai rinvenuti e ci porta a ridiscutere tutte le convinzioni fin ora raggiunte sull’evoluzione dei vertebrati”, ha commentato Long.
  La cosa piu’ interessante per i ricercatori e’ stato il fatto di poter certificare un metodo di riproduzione cosi’ sofisticato in un reperto cosi’ antico. “Questa scoperta ci dimostra che il parto e la schiusa delle uova sono due processi riproduttivi che si svilupparono forse in contemporanea e non in successione come si e’ sempre pensato”, ha spiegato la dottoressa Kate Trinajstic.
  L’esistenza dell’embrione e di un cordone ombelicale certifica anche il piu’ antico caso di fertilizzazione interna nel mondo animale, in pratica il primo esempio di sesso con penetrazione. Lunga circa 25 centimetri la “madre pesce” apparteneva a un gruppo estinto di vertebrati, i placodermi, diffusi nell’era medio paelozoica che va dai 420 ai 350 milioni di anni fa. I placodermi erano dei dinosauri marini che dominarono i mari, i fiumi e i laghi della terra per 70 milioni di anni. Nel fossile ritrovato si possono distinguere nitidamente le forme dell’embrione all’interno dell’utero materno e il cordone ombelicale calcificato che unisce la madre al piccolo. Solo dopo una delicatissima opera di pulitura del fossile tramite speciali acidi i due ricercatori si sono resi conto della particolarita’ del reperto. Come racconta la dottoressa Trinajstic: “Una volta pulito il fossile abbiamo visto l’embrione seduto nella pancia della madre, era conservato in maniera perfetta”. Dopo una successiva analisi del fossile col microscopio elettronico e una termografia computerizzata gli scienziati hanno potuto vedere anche i vasi sanguigni del cordone ombelicale. Secondo le ricostruzione degli scienziati il pesce e il suo piccolo morirono a causa di un improvviso abbassamento dei livelli di ossigeno nell’acqua.
  Caduta sul fondale, la “madre pesce” sarebbe poi stata ricoperta da un fango limaccioso che ne ha consentito la conservazione nei secoli.(AGI)

CORREZIONI:

Ovviamente i placodermi non erano dinosauri marini, bensì pesci.

LINKS:

1 – Video presentazione del reperto – youtube

2 – Articolo scientifico di riferimento – Live birth in the Devonian period (Nature)

3 – Foto e illusttrazioni – Nature.com

maggio 31, 2008 Posted by | - Pesci / Fishes, Articolo sc. di riferimento, Oceania, P - Ritrovamenti fossili, Paleontology / Paleontologia, Video | , , , , | Lascia un commento