Il blog dedicato ai Paleontologi !!!!

2009-05-27 – Peru`: scoperto bradipo fossile (fossil Sloth)

Five-million-year old sloth fossil found in Peru

click here for video

LIMA (Reuters) – The nearly intact fossil of an ancient sloth that lived 5 million years ago has been unearthed in Peru, a find about 4 million years older than similar ones discovered in the Americas, researchers said.

The sloth was found beneath the cement floor of a house in the Andean region of Espinar in southern Peru when workers were installing a water system. Parts of a giant armadillo that has also been dated to 5 million years ago were also found nearby.

The sloth, about 10 feet long, was an herbivore and lived during the Mio-Pliocene era, said paleontologist Rodolfo Salas of Peru’s Natural History Museum and one of the scientists on the dig sponsored by the French government.

“This skeleton of the sloth is especially important as it is the first complete skeleton of its kind that is 5 million years old in the Americas,” he told Reuters. “Previously, discoveries have been made of partial skeletons of similar animals, but from the Pleistocene era, meaning from the last million years.”

The sloth was found at 13,000 feet above sea level.

Salas said the sloth was relatively small compared with other animals of its type and would help researchers better understand evolution of mammals in the Andes.

Peru’s dry climate has helped preserve thousands of fossils from the Pacific coast to the Andes highlands, making it a favorite of fossil hunters.

(Reporting by Carlos Valdez; Writing by Terry Wade; Editing by Peter Cooney)



maggio 27, 2009 Posted by | - Mammiferi, America Southern, An. Vertebrates, Cenozoic, Multimedia, P - Geositi, P - Paleoantropologia, P - Ritrovamenti fossili, Paleontology / Paleontologia, Video | , , , , | Lascia un commento

2009-05-10 – Utah, USA: ritrovata una tartaruga fossile incinta (fossil pregnant turtle)

Rare prehistoric pregnant turtle found in Utah

At least three eggs are visible from the outside of the fossil, and Montana State University researchers this week have been studying images taken from a CT scan in search of others inside.

Montana State graduate student Michael Knell says the turtle was probably about a week from laying her eggs when she died and became entombed for millions of years in sandstone.

The fossil was found in 2006 in a remote part of Grand Staircase-Escalante National Monument. The eggs weren’t discovered until after it sat in storage for two years and was being re-examined by a volunteer.

This image provided Montana State University shows CT technician, Tanya Spence preparing to run a 75 million-year-old turtle fossil through a CT scanner at Deaconess Hospital in Bozeman, Mont. (AP Photo/Montana State University, Kelly Gorham)

This image provided Montana State University shows CT technician, Tanya Spence preparing to run a 75 million-year-old turtle fossil through a CT scanner at Deaconess Hospital in Bozeman, Mont. (AP Photo/Montana State University, Kelly Gorham)

maggio 10, 2009 Posted by | - Rettili, 1 Cretaceo, America Northern, An. Vertebrates, Articolo sc. di riferimento, Mesozoic, P - Preservazione eccezionale, P - Ritrovamenti fossili, Paleontology / Paleontologia, X - Nature | , , , , , , , , , | Lascia un commento

2009-02-14 – Aurorachelys, tartaruga fossile dalla Groenlandia (Greenlad, turtle fossil)

February 13, 2009

Ancient turtle fossil found on Axel Heiberg Island

Shell dates from warm period 90 million years ago


Geologists from the University of Rochester have uncovered a 90 million-year-old fossil of a tropical freshwater Asian turtle in Nunavut’s High Arctic.

The fossil was found in a slab of ancient basalt on Axel Heiberg Island.

The turtle, dubbed Aurorachelys, or aurora turtle, lived in the region 90 million years ago when polar temperatures averaged above 14 C, similar to those found in today’s northern Florida.

Turtles swam in Nunavut’s High Arctic 90 million years ago, say geologists who announced the find of this fossil turtle shell this week.

A paper on the fossil, published in the Feb. 1 journal Geology, suggests that carbon dioxide pouring into the atmosphere from volcanic activity during that period may have caused a “super-greenhouse” effect, boosting temperatures in the polar region.

“We’re talking about extremely warm, ice-free conditions in the Arctic region, allowing migrations across the pole,” said John Tarduno, professor of geophysics at the University of Rochester and leader of the team that found the turtle fossil, in a news release on the find.

The turtle resembles a kind of freshwater turtle found in Mongolia, so its presence in the High Arctic suggests that it may have migrated from Asia to North America by floating on a freshwater layer on top of the then-warm, salty Arctic Ocean.

Tarduno’s team found the fossil in 2006 when they went to the Arctic to study paleo-magnetism- that is, the Earth’s magnetic field in the far distant past.

Tarduno said study of the magnetism in rocks where the fossil was found rules out the possibility that the fossil came from southern waters. The turtle was clearly a native of the area, Tarduno noted.

At the time the aurora turtle lived, the Arctic Ocean was probably even more separated from the global oceanic circulation system than it is today, Tarduno said, and rivers would have poured fresh water into the ancient sea.

Fresh water is lighter than sea water, so Tarduno thinks fresh water may have rested on top of the salty water, allowing a freshwater animal such as the aurora turtle to migrate.

According to the news release, Tarduno also believes volcanoes could have produced a series of islands along an underwater mountain range in the Arctic Ocean called the Alpha Ridge.

If the ridge poked out above the surface of the water at one time, it would have given the turtles and other species the ability to island-hop all the way from ancient Russia to Canada, Tarduno said.

In recent years, Tarduno has uncovered fossils of other warm-water species in the High Arctic, such as crocodile-like beasts, which once thrived there 90 million years ago.


febbraio 14, 2009 Posted by | - Rettili, 1 Cretaceo, An. Vertebrates, Mesozoic, P - Ritrovamenti fossili, Paleontology / Paleontologia | , , , , , , | Lascia un commento

2009-02-03 – La tartaruga fossile e il polo “tropicale” (Turtle fossil and tropical Artic)


L’Artide 90 milioni di anni fa era un posto molto piu’ temperato: senza ghiacci e con passaggio migratorio degli animali preistorici. Lo sostengono alcuni scienziati dopo la scoperta di un fossile di tartaruga asiatica nell’Artide canadese. Secondo i ricercatori, tra cui Donald Brinkman del Royal Tyrell Museum dell’Alberta, la tartaruga tipica della Mongolia, chiamata ‘tartaruga aurora’, con il guscio quasi perfettamente rotondo, esistente all’epoca dei dinosauri e da tempo estinta, avrebbe percorso migliaia di chilometri dal suo habitat originario nelle acque dolci dell’Asia passando non dall’Alaska ma direttamente dal polo Nord. Questo proverebbe che nel polo Nord le temperature in passato erano molto piu’ temperate, al punto da rendere l’Artide un percorso migratorio delle creature preistoriche. Secondo i ricercatori un ‘super effetto serra’, forse originato da eruzioni vulcaniche, causo’ 90 milioni di anni fa un’enorme emissione di anidride carbonica scaldando i poli ed aprendo nuovi passaggi per gli animali migratori, comprese le tartarughe. (ANSA). COR-DI
02/02/2009 19:47



Turtle fossil shows how ‘super-greenhouse effect’ created tropical Arctic

The discovery of a fossilised ancient turtle reveals the North Pole was once “extremely” warm and tropical, scientists said.

Turtle fossil shows how 'super-greenhouse effect' created tropical Arctic
The North Pole: “extremely” warm and tropical millions of years ago Photo: GETTY IMAGES

Animals migrated from Asia to North America directly across the formerly frost-free Arctic Ocean, new evidence shows.

Geologists made the breakthrough after discovering the fossil of a freshwater Asian turtle – dating back millions of years – in Canada.

John Tarduno, a US-based professor of geophysics at the University of Rochester, said: “We’ve known there’s been an interchange of animals between Asia and North America in the late cretaceous period, but this is the first example we have of a fossil in the High Arctic region showing how this migration may have taken place.

“We’re talking about extremely warm, ice-free conditions in the Arctic region, allowing migrations across the pole.”

Numerous rivers from the adjacent continents would have poured fresh water into the ancient Arctic sea, he said.

Fresh water, which is lighter than marine water, may have rested on top of the salty ocean water allowing animals such as the turtle to migrate with relative ease.

The professor, who published his findings in the journal Geology, added: “We found this turtle right on top of the last flood basalts – a large stretch of lava from a series of giant volcanic eruptions.

“That leads us to believe that the warming may have been caused by volcanoes pumping tremendous amounts of carbon dioxide into the Earth’s atmosphere.

“There is evidence that this volcanic activity happened all around the planet – not just the Arctic.

“If it all happened on a short-enough timescale, it could cause a super-greenhouse effect.”

The research team plans to return to the Arctic to look for more fossils.


febbraio 3, 2009 Posted by | - Rettili, 1 Cretaceo, An. Vertebrates, Antartide, Lang. - Italiano, Mesozoic, P - Paleoclimatologia, Paleontology / Paleontologia | , , , , , , , , , | Lascia un commento

2008-10-17 – Colombia: Il più grande serpente fossile mai trovato (giant fossil snake)

Presentata al SVP Meeting la scoprta del più antico serpente fossile mai ritrovato.

Sono state scoperte in Colombia alcune vertebre (dieci centimetri di diametro, circa il doppio di quelle del più grande serpente attuale, l’Anaconda) e frammenti di costole di un serpente antenato dell’attuale Boa e risalenti a 60 milioni di anni fa. Grazie tali reperti si è stimato che l’esemplare completo doveva avere una lunghezza di 12,8 metri e un peso di 1,27 tonnellate


Fossil find may document largest snake

The ancient bonecrusher likely weighed more than a ton

CLEVELAND — Rocks beneath a coal mine in Colombia have yielded fossils of what could be the world’s largest snake, a relative of today’s boa constrictor that was 12.8 meters long and weighed more than a ton.

Few of today’s snakes exceed 9 meters in length, says Jonathan Bloch, a vertebrate paleontologist at the Florida Museum of Natural History at the University of Florida in Gainesville. Some of the snakes that lived about 60 million years ago, however, would have dwarfed their modern kin, he reported Wednesday in Cleveland at the annual meeting of the Society of Vertebrate Paleontology.

At a site in northern Colombia, Bloch and his colleagues unearthed the partial remains of an ancient snake. Each of the dozen or so vertebrae in that body segment measured about 10 centimeters across. That’s about twice the width of the largest vertebra taken from a 6-meter–long, modern-day anaconda, another modern relative, Bloch notes.

None of the ribs included in the fossil are complete, but the size and curvature of the fragments that remain indicate that the snake “would have had trouble fitting though the door into your office,” he adds. The gargantuan fossils represent an as yet unnamed species.

Estimating a snake’s length from fragmentary remains is difficult because most of the creature’s vertebrae differ only in their size, not in their proportions. Bloch and his colleagues can’t readily determine whether the segment that they unearthed came from the thickest portion of the snake, so their estimates of the snake’s size and weight are minimum values. The researchers contend that the ancient snake they discovered would have stretched at least 12.8 meters and weighed at least 1.27 metric tons.

Even one complete vertebra can enable scientists to make good estimates of a snake’s minimum length, says S. Blair Hedges, an evolutionary biologist at Penn State University in University Park. “This [snake] is definitely bigger than any modern-day snake,” he notes. The record length for a living species belongs to a reticulated python that measured 10 meters long.

The rocks that once entombed the snake remains had been laid down as clay-rich sediments on floodplains near a coastline about 60 million years ago, Bloch says. Other fossils excavated from the same layers include an aquatic turtle whose shell was 2 meters across and whose skull was the size of a dinner plate. So far, the paleontologists haven’t unearthed any mammal fossils at the site, so it’s a mystery as to what these creatures preyed upon.

Other links (updated on 2008-10-21 18:07 Italy):


ottobre 17, 2008 Posted by | - Rettili, 1 Cretaceo, America Southern, P - Ritrovamenti fossili, Paleontology / Paleontologia, SVP Meeting | , , , , , , | Lascia un commento

2008-09-22 – Pesce fossile con dita (Panderichthys, 4) (divulgazione sc. ITA)

Evoluzione degli arti

Le dita dei pesci primordiali

L’assenza nei pesci dei meccanismi genetici per lo sviluppo delle dita aveva fatto ritenere che esse si fossero sviluppate solo dopo la colonizzazione della terraferma

Finora si riteneva che i tetrapodi, i primi animali terrestri a quattro zampe, fossero stati anche i primi organismi dotati di dita; ora una ricerca condotta da paleontologi dell’Università di Uppsala mostra che non è così. Come spiega in un articolo in corso di pubblicazione su “Nature”, Catherine Boisvert è infatti riuscita a identificare, attraverso un esame a raggi X dei fossili di Panderichthys – la presenza di dita rudimentali in questa specie di transizione fra i pesci e gli animali terricoli.

Circa 380 milioni di anni fa alcuni antenati dei pesci attuali si sono evoluti nei tetrapodi, passando per diverse forme intermedie. I ricercatori si sono sempre chiesti se le dita siano comparse per la prima volta in questi progenitori di tutti gli uccelli, mammiferi, crostacei e anfibi, o se esse si fossero sviluppate a partire da elementi già presenti nelle forme ittiche da cui essi derivavano.

Ricerche precedenti che avevano esaminato i geni necessari allo sviluppo delle pinne nel pesce zebra (Danio rerio) – uno dei pesci più prossimi ai celacantidi, i “fossili viventi” che si ritiene derivino direttamente dagli antichi progenitori dei tetrapodi – per poi confrontarli con quelli che regolano lo sviluppo degli arti nel topo, avevano mostrato l’assenza nel pesce dei meccanismi genetici necessari allo sviluppo delle dita. Questa osservazione aveva condotto alla conclusione che esse fossero realmente apparse solamente nei tetrapodi.

Esaminando tuttavia fossili di Panderichthys con tecniche di tomografia computerizzata nel corso di uno studio per la ricostruzione dell’immagine tridimensionale dell’animale, Catherine Boisvert ha potuto scoprire la presenza finora passata del tutto inosservata, di rudimenti di dita. Strutture analoghe erano state in effetti rilevate in esemplari fossili di “Tiktaalik”, che tuttavia è una specie molto più vicina ai tetrapodi del Panderichthys. (gg)

PAROLE CHIAVE – dita Tiktaalik

settembre 22, 2008 Posted by | - Pesci / Fishes, Europa, Lang. - Italiano, P - Evoluzione, P - Ritrovamenti fossili, Paleontology / Paleontologia | , , , , , | Lascia un commento

2008-09-22 – Pesce fossile con dita (Panderichthys, 3) (divulgazione sc.)

Primordial Fish Had Rudimentary Fingers

ScienceDaily (Sep. 21, 2008) — Tetrapods, the first four-legged land animals, are regarded as the first organisms that had fingers and toes. Now researchers at Uppsala University can show that this is wrong. Using medical x-rays, they found rudiments of fingers in the fins in fossil Panderichthys, the “transitional animal,” which indicates that rudimentary fingers developed considerably earlier than was previously thought.

Our fish ancestors evolved into the first four-legged animals, tetrapods, 380 million years ago. They are the forerunners of all birds, mammals, crustaceans, and batrachians. Since limbs and their fingers are so important to evolution, researchers have long wondered whether they appeared for the first time in tetrapods, or whether they had evolved from elements that already existed in their fish ancestors.

When they examined genes that are necessary for the evolution of fins in zebrafish (a ray-finned fish that is a distant relative of coelacanth fishes) and compared them with the gene that regulates the development of limbs in mice, researchers found that zebrafish lacked the genetic mechanisms that are necessary for the development of fingers. It was therefore concluded that fingers appeared for the first time in tetrapods.

This reading was supported by the circumstance that the fossil Panderichthys, a “transitional animal” between fish and tetrapod, appeared to lack finger rudiments in their fins.

In the present study, to be published in Nature, medical x-rays (CT scans) were used to reconstruct a three-dimensional image of Panderichthys fins. The results show hitherto undiscovered elements that constitute rudiments of fingers in the fins.

Similar rudiments have been demonstrated once in the past, two years ago in Tiktaaliks, which is a more tetrapod-like group. Together with information about fin development in sharks, paddlefish, and Australian lungfish, the scientists can now definitively conclude that fingers were not something new in tetrapods.

“This was the key piece of the puzzle that confirms that rudimentary fingers were already present in ancestors of tetrapods,” says Catherine Boisvert.

Adapted from materials provided by Uppsala University
other links:
Ancient fish had ‘fingers’ before acquiring fins
Sify – 6 ore fa
Washington: The analysis of a newly discovered fossil skeleton has revealed that before it acquired fins, an ancient fish sported something like fingers
Fish Gave Us The Finger
Scientific American – 12 ore fa
Fish from almost 400 million years ago appear to have bones in their fins that predisposed future animals to the development of fingers.
Digital evolution: early fish had primitive fingers, says study
AFP – 17 ore fa
PARIS (AFP) — Scientists have traced the origin of fingers and toes to fish-like creatures that roamed the seas 380 million years ago, according to a new
Fish with fingers are evolution’s ‘missing link’ – 22 ore fa
Finger-like divisions found in the fins of ancient fish have been hailed as a “missing link” in our evolution. By Richard Alleyne Scientists studying the
Researchers Find Primative Finger Bones in Ancient Fish
Discover Magazine – 3 ore fa
Researchers have found the first small finger-like bones in the fins of a fish that lived 380 million years ago, about 15 million years before the first
Ancient fish grows fingers
Metro – 8 ore fa
by AGENCY – Monday, September 22, 2008 Fishy fact: An ancient species of fish developed primitive fingers, suggesting that organisms developed digits far
Scientists discover why we all have fish fingers
Daily Mail – 15 ore fa
By Daily Mail Reporter You may think you have little or no connection to the ugly-looking customer pictured below. After all, you’re an intelligent and
Discovery of fish with fingers gives evolution new twist
The Tech Herald – 17 ore fa
by Rich Bowden – Sep 21 2008, 21:52 Swedish scientists studying a fish which lived 385 million years ago have made a remarkable discovery which pushes back
Origin of fingers seen in fish
World Science – 17 ore fa
Finger-like divisions in the fins of ancient fish are the predecessors of our fingers and toes, according to a study published online in the research
Ancient fingers and toes
Scientist – 22 ore fa
Were animals with four limbs the first to evolve fingers and toes– or did such digits evolve long before? A study published today (September 21) in Nature
Fossil Fish Found with “Fingers” – 7 ore fa
A fossilised skeleton has shown an ancient fish with finger-like digits hidden beneath the skin and scales on the Panderichtys’s fin.

settembre 22, 2008 Posted by | - Pesci / Fishes, Europa, P - Evoluzione, P - Ritrovamenti fossili, Paleontology / Paleontologia | , , , , , , , | Lascia un commento

2008-09-22 – Pesce fossile con dita (Panderichthys, 1) (Abstract from Nature)


Nature advance online publication 21 September 2008 | doi:10.1038/nature07339; Received 12 June 2008; Accepted 14 August 2008; Published online 21 September 2008


The pectoral fin of Panderichthys and the origin of digits

Catherine A. Boisvert1, Elga Mark-Kurik2 & Per E. Ahlberg1

  1. Subdepartment of Evolutionary Organismal Biology, Department of Physiology and Developmental Biology, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18A, 752 36 Uppsala, Sweden
  2. Institute of Geology at Tallinn University of Technology, Ehitajate tee 5, 19086 Tallinn, Estonia

Correspondence to: Catherine A. Boisvert1 Correspondence and requests for materials should be addressed to C.A.B. (Email:


One of the identifying characteristics of tetrapods (limbed vertebrates) is the presence of fingers and toes. Whereas the proximal part of the tetrapod limb skeleton can easily be homologized with the paired fin skeletons of sarcopterygian (lobe-finned) fish, there has been much debate about the origin of digits. Early hypotheses1 interpreted digits as derivatives of fin radials, but during the 1990s the idea gained acceptance that digits are evolutionary novelties without direct equivalents in fish fin skeletons. This was partly based on developmental genetic data2, but also substantially on the pectoral fin skeleton of the elpistostegid (transitional fish/tetrapod) Panderichthys, which appeared to lack distal digit-like radials3. Here we present a CT scan study of an undisturbed pectoral fin of Panderichthys demonstrating that the plate-like ‘ulnare’ of previous reconstructions is an artefact and that distal radials are in fact present. This distal portion is more tetrapod-like than that found in Tiktaalik 4 and, in combination with new data about fin development in basal actinopterygians5, sharks6 and lungfish7, makes a strong case for fingers not being a novelty of tetrapods but derived from pre-existing distal radials present in all sarcopterygian fish.

NB – SUPPLEMENTARY INFORMATIONS (with video and pictures)

settembre 22, 2008 Posted by | - Pesci / Fishes, Articolo sc. di riferimento, Europa, Multimedia, P - Evoluzione, P - Ritrovamenti fossili, Paleontology / Paleontologia, Video | , , , , , , , , , , , , | 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


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

In mostra l’ammonite più grande del mondo

Presentata in una mostra in Germania l’ammonite più grande del mondo (Parapuzosia seppenradensis) che ha vinto il premio come fossil dell’anno 2008 (Fossil des Jahres 2008).

Parapuzosia seppenradensis

Parapuzosia seppenradensis



see the pdf: fossil-des-jahres

settembre 21, 2008 Posted by | - Molluschi, Collezionismo, Curiosità, Europa, Mostre & Fiere, Paleontology / Paleontologia | , , , , , , , , , | Lascia un commento