Tag Archives: Miocene

Kenyan fossil fish discoveries

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Kenyan fossil fish

From the Ludwig-Maximilians-Univerität München in Germany:

Fossil fishes found in Kenya

Munich, 03/14/2013

A research team led by LMU paleontologist Bettina Reichenbacher has uncovered a rich trove of fossil fish in Kenya’s Rift Valley.

A paleontological expedition to the Tugen Hills in Kenya, led by LMU’s Professor Bettina Reichenbacher, has discovered assemblages of fossil fish at eight previously unexplored localities. “Not only is it very rare to uncover so many specimens of fossil fish, those we have found are also very well preserved,” says Reichenbacher.

The new fossils are between 10 and 12 million years old, and will shed light on the evolutionary history of freshwater fish in East Africa. Moreover, the find is of wider significance, as the anatomy of the various forms is not only of interest to paleontologists. The specimens also provide insights into the ecological and climatic conditions that prevailed in the region during the Middle Miocene. “For instance, we can tell whether these fish lived in tropical lakes or in drier habitats that were subject to periodic droughts,” says Bettina Reichenbacher. This kind of information will help researchers pinpoint the onset of dry conditions in the Middle Miocene, when tropical forests were gradually replaced by open grassland with less tree cover. This is of great interest, as the transformation of woodland into savannah is thought to have favored the diversification of hominids, the evolutionary lineage to which modern humans belong.

The new find site is located in the section of the Rift Valley that runs through Kenya. A whole succession of exciting finds made here by paleoanthropologists since the middle of the last century has made this area one of the most important sources of hominid fossils in the world, and has led to its being dubbed “the cradle of humanity.”

Previously unknown species

“We assume that the fish succumbed to the effects of volcanic activity. The jaws of many individuals are agape, which suggests that they were asphyxiated,” says Bettina Reichenbacher. Volcanism could also account for their good state of preservation. They may have been rapidly buried under layers of volcanic ash, which would have protected them from early post-mortem decay and subsequent erosion.

The researchers expect to identify previously unknown species among the many specimens that they have recovered. Africa today is home to approximately 3000 species of freshwater fish, but this diversity is not reflected in the known fossil record. Fewer than 60 fossil species have been described from the continent, partly because most finds consist of isolated teeth and bones. “Further investigation of the fossils we have found will provide us with valuable information about the evolution of the fish fauna not only in Kenya, but in the whole of Africa,” says Bettina Reichenbacher.

The expedition was supported by the Deutsche Forschungsgemeinschaft and the Bavarian State Collections for Paleontology and Geology.

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Crocodile, mammal fossil discoveries in Panama

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A life reconstruction of Culebrasuchus mesoamericanus, one of two newly discovered species from the early Miocene in Panama / Danielle Byerley/ Florida Museum of Natural History

From the University of Florida in the USA:

Scientists Discover New Crocodilian, Hippo-Like Species From Panama

University of Florida paleontologists have discovered remarkably well-preserved fossils of two crocodilians and a mammal previously unknown to science during recent Panama Canal excavations that began in 2009.

The two new ancient extinct alligator-like animals and an extinct hippo-like species inhabited Central America during the Miocene about 20 million years ago. The research expands the range of ancient animals in the subtropics — some of the most diverse areas today about which little is known historically because lush vegetation prevents paleontological excavations — and may be used to better understand how climate change affects species dispersal today. The two studies appear online today in the same issue of the Journal of Vertebrate Paleontology.

The fossils shed new light on scientists’ understanding of species distribution because they represent a time before the formation of the Isthmus of Panama, when the continents of North and South America were separated by oceanic waters.

“In part we are trying to understand how ecosystems have responded to animals moving long distances and across geographic barriers in the past,” said study co-author Jonathan Bloch, associate curator of vertebrate paleontology at the Florida Museum of Natural History on the UF campus. “It’s a testing ground for things like invasive species – if you have things that migrated from one place into another in the past, then potentially you have the ability to look at what impact a new species might have on an ecosystem in the future.”

The research was funded by the National Science Foundation Panama Canal Partnerships in International Research and Education project, which supports paleontological excavation of the canal during construction expected to continue through 2014.

“We’re very fortunate we could get the funding for PIRE to take advantage of this opportunity — we’re getting to sample these areas that are completely unsampled,” said Alex Hastings, lead author of the crocodilian study and a visiting instructor at Georgia Southern University who conducted the research for the project as a UF graduate student.

Researchers analyzed all known crocodilian fossils from the Panama Canal, including the oldest records of Central American caimans, which are cousins of alligators. The more primitive species, named Culebrasuchus mesoamericanus, may represent an evolutionary transition between caimans and alligators, Hastings said.

“You mix an alligator and one of the more primitive caimans and you end up with this caiman that has a much flatter snout, making it more like an alligator,” Hastings said. “Before this, there were no fossil crocodilian skulls known from Central America.”

Christopher Brochu, an assistant professor of vertebrate paleontology in the department of geoscience at the University of Iowa, said “the caiman fossil record is tantalizing,” and the new data shows there is still a long way to go before researchers understand the group.

“The fossils that are in this paper are from a later time period, but some of them appear to be earlier-branching groups, which could be very important,” said Brochu, who was not involved with the study. “The problem is, because we know so little about early caiman history, it’s very difficult to tell where these later forms actually go on the family tree.”

The new mammal species researchers described is an anthracothere, Arretotherium meridionale, an even-toed hooved mammal previously thought to be related to living hippos and intensively studied on the basis of its hypothetical relationship with whales. About the size of a cow, the mammal would have lived in a semi-aquatic environment in Central America, said lead author and UF graduate student Aldo Rincon.

“With the evolution of new terrestrial corridors like this peninsula connecting North America with Central America, this is one of the most amazing examples of the different kind of paths land animals can take,” Rincon said. “Somehow this anthracothere is similar to anthracotheres from other continents like northern Africa and northeastern Asia.”

Researchers also name a second crocodilian species, Centenariosuchus gilmorei, after Charles Gilmore, who first reported evidence of crocodilian fossils collected during construction of the canal 100 years ago. The genus is named in honor of the canal’s centennial in 2014.

Researchers will continue excavating deposits from the Panama Canal during construction to widen and straighten the channel and build new locks. The project is funded by a $3.8 million NSF grant to develop partnerships between the U.S. and Panama and engage the next generation of scientists in paleontological and geological discoveries along the canal.

Study co-authors include Bruce MacFadden of UF and Carlos Jaramillo of the Smithsonian Tropical Research Institute.

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Californian fossil whale discovery

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This vide is called Whales evolution.

By Sarah Laskow in the USA:

New whale species discovered under highway

In California, a road crew — which, according to state law, must for real include an on-site paleontologist and an archaeologist — dug up a boneyard of hundreds of marine mammals, ScienceNOW reports. Among those bones, they came up 30 whale skulls. And four of those skulls belong to “four newly identified species of toothed baleen whale — a type of whale that scientists thought had gone extinct 5 million years earlier.”

ScienceNOW explains:

“The new fossils date to 17 to 19 million years ago, or the early-mid Miocene epoch, making them the youngest known toothed [baleen] whales. Three of the fossils belong to the genus Morawanocetus, which is familiar to paleontologists studying whale fossils from Japan, but hadn’t been seen before in California.”

The fourth new species was a different genus and was bigger than whales this old are expected to be. And, like a boss, it ate sharks.

Meredith Rivin, the paleontologist who’s been analyzing these fossils, is still working on an official paper presenting her findings, but we’re already pretty sure this is the best possible result of digging a new highway.

Talking about whales: harbour porpoises in the Netherlands: here.

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Strange fossil mammal discovery

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From Discovery News:

Scrappy Mammal Survived Dinosaur Extinction

Jennifer Viegas
Analysis by Jennifer Viegas
Mon Nov 19, 2012 02:55 PM ET

Necrolestes patagonensis, Reconstruction by Jorge Gonzalez, Copyright Guillermo W. Rugier

A scrappy family of mammals with unusual, mismatched features moved underground and, like living in a perpetual bomb shelter, managed to survive the mass extinction event 65 million years ago that wiped out the world’s non-avian dinosaurs. We know this thanks to new research on the fossil mammal Necrolestes patagonensis, whose name translates to “grave robber,” referring to its burrowing and underground lifestyle. The animal, described in the latest Proceedings of the National Academy of Sciences, had an upturned snout, a sturdy body structure, and short, wide legs.

It lived 16 million years ago, long after the dinosaur demise. But it was found to be related to another fossil mammal, Cronopio, which belonged to the Meridiolestida, a little-known group of extinct mammals from the Late Cretaceous and early Paleocene (100–60 million years ago) of South America.

Cronopio and Necrolestes share a number of features in common, including the fact that they are the only known mammals to have single-rooted molars. Most mammals have double-rooted molars.

The animals were so odd and puzzling, at least to modern eyes, that they mystified scientists for years.

“Necrolestes is one of those animals in the textbooks that would appear with a picture and a footnote, and the footnote would say ‘we don’t know what it is,’” co-author John Wible of the Carnegie Museum of Natural History said in a press release.

For a long time it was thought that “grave robber” was a marsupial. Further analysis, however, found that Necrolestes actually belonged in a completely unexpected branch of the evolutionary tree believed to have died out 45 million years earlier than the time of Necrolestes.

This is an example of the Lazarus effect, in which a group of organisms is found to have survived far longer than originally thought. (“Lazarus” comes from the Bible story about how Jesus raised a man from the dead.)

“It’s the supreme Lazarus effect,” said Wible. “How in the world did this animal survive so long without anyone knowing about it?”

A good example of the Lazarus effect is the ginkgo tree, thought to be extinct until it was rediscovered growing in China in the 17th century.

The researchers believe that Necrolestes’s supreme burrowing adaptations are exactly what enabled it to survive for 45 million years longer than its relatives.

“There’s no other mammal in the Tertiary of South America that even approaches its ability to dig, tunnel, and live in the ground,” explained Wible. “It must have been on the edges, in an ecological niche that allowed it to survive.”

See also here.

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Vulture fossil discovery in Nebraska, USA

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This video is called Vulture restaurant.

From PLOS ONE:

A Late Miocene Accipitrid (Aves: Accipitriformes) from Nebraska and Its Implications for the Divergence of Old World Vultures

Abstract

Background

Old World vultures are likely polyphyletic, representing two subfamilies, the Aegypiinae and Gypaetinae, and some genera of the latter may be of independent origin. Evidence concerning the origin, as well as the timing of the divergence of each subfamily and even genera of the Gypaetinae has been elusive.

Methodology/Principal Findings

Compared with the Old World, the New World has an unexpectedly diverse and rich fossil component of Old World vultures. Here we describe a new accipitriform bird, Anchigyps voorhiesi gen. et sp. nov., from the Ash Hollow Formation (Upper Clarendonian, Late Miocene) of Nebraska. It represents a form close in morphology to the Old World vultures. Characteristics of its wing bones suggest it was less specialized for soaring than modern vultures. It was likely an opportunistic predator or scavenger having a grasping foot and a mandible morphologically similar to modern carrion-feeding birds.

Conclusions/Significance

The new fossil reported here is intermediate in morphology between the bulk of accipitrids and the Old World gypaetine vultures, representing a basal lineage of Accipitridae trending towards the vulturine habit, and of its Late Miocene age suggests the divergence of true gypaetine vultures, may have occurred during or slightly before the Miocene.

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Giant carnivorous fossil whale discovered

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This video says about itself:

29 June 2010 | 1:36

The newly discovered Leviathan melvillei was a prehistoric sperm whale with massive teeth, each a foot long. It ate other whales.

From the BBC today:

‘Sea monster’ whale fossil unearthed

By Pallab Ghosh
Science correspondent, BBC News

Researchers have discovered the fossilised remains of an ancient whale with huge, fearsome teeth.

Writing in the journal Nature, the scientists have dubbed the 12 million-year-old creature “Leviathan”.

It is thought to have been more than 17m long, and might have engaged in fierce battles with other giant sea creatures from the time.

Leviathan was much like the modern sperm whale in terms of size and appearance.

But that is where the similarity ends. While the sperm whale is a relatively passive animal, sucking in squid from the depths of the ocean, Leviathan was an aggressive predator.

According to Dr Christian de Muizon, director of the Natural History Museum in Paris, Leviathan could have hunted out and fed on large sea creatures such as dolphins, seals and even other whales.

“It was a kind of a sea monster,” he said.

“And it’s interesting to note that at the same time in the same waters was another monster, which was a giant shark about 15m long. It’s possible that they might have fought each other”.

The researchers speculate that Leviathan was able to feed on very large prey up to 8m long. It would catch the prey in its huge jaws and tear it apart quickly and effectively with its giant teeth.

A 3m-long fossilised skull of the creature was discovered by researchers in southern Peru in 2008. Dr de Muizon’s student, Olivier Lambert was among them.

“It was the last day of our field trip when one of our colleagues came and told us that he thought he’d found something very interesting. So we joined him and he showed it to us,” he said.

“We immediately saw that it was a very large whale and when we looked closer we saw it was a giant sperm whale with huge teeth.”

The teeth were more than twice the length and diameter of those found in modern sperm whales and they were on the upper and lower jaws.

Dr Christian de Muizon compares the giant’s teeth with those of a sperm whale

Sperm whales only have teeth on their lower jaw.

Dr Lambert and his colleagues had speculated that such a fierce creature might once have existed on the basis of discoveries of individual teeth.

Now, the discovery of the skull means that the Leviathan is not merely the stuff of myth and legend.

“Finally we found it,” said Dr Lambert. ” It was a very exciting moment”.

The researchers do not know why this ancient whale died out. They speculate that the ecology and environment changed so that the creature had to change its feeding habits.

That may have led to the emergence of today’s much gentler sperm whales, with the carnivorous niche filled by killer whales as conditions swung back again.

The authors of the report in Nature, who are all whale experts, are fans of the novel Moby Dick, which involves a ferocious white sperm whale.

So taken are they with the novel that they decided to dedicate their discovery to the author, Herman Melville, and give the creature its full scientific name of Leviathan melvillei.

See also here. And here.

The genus name Leviathan, proposed in this Letter for a new fossil physeteroid from the Miocene of Peru, is preoccupied by Leviathan Koch, 1841 (ref. 1), a junior subjective synonym of Mammut Blumenbach, 1799 (ref. 2). We propose here a replacement name Livyatan gen. nov. The type species is placed in this genus to form the binomial Livyatan melvillei. The diagnosis and content of the new genus follow our Letter. ‘Livyatan’ is a Hebrew name applied to large marine monsters in popular and mythological stories: here.

The inspiration behind Moby Dick: here.

Whale fossils from the Faiyum, Egypt: here.

Sperm whale sighting off Torbay, South Devon: here.

August 2010. The Torbay sperm whale has been seen again – and this time it is thought it might have a calf with it. The whale was spotted from the clifftops at around 6.30am on August 5th about 150 yards off North Preston Beach. Paignton resident Ken Rowe, a former oil industry worker who has been used to seeing large fish and sea mammals all his working life across the world, couldn’t thought he was seeing things: here.

Sperm whales & giant squid may be mortal enemies: here.

‘Superpod’ of 1,000 dolphins spotted off Skye: here.

Fossil koala species

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From the University of New South Wales in Australia:

Loud and lazy but didn’t chew gum: Ancient koalas

Skull fragments of prehistoric koalas from the Riversleigh rainforests of millions of year ago suggest they shared the modern koala‘s “lazy” lifestyle and ability to produce loud “bellowing” calls to attract mates and provide warnings about predators.

However, the new findings published as the featured cover article in the current issue of The Journal of Vertebrate Paleontology suggest that the two species of koalas from the Miocene (24 to five million years ago) did not share the uniquely specialized eucalyptus leaf diet of the modern koala (Phascolarctos cinereus).

The shift to a wholly eucalyptus diet by modern koalas was an adaptation that probably came later as Australia drifted north, causing its rainforests to retreat and Eucalypts to become the dominant tree of most Australian forests and woodlands.

Modern koalas – the sole living member of the diprotodontian marsupial family Phascolarctidae –are among the largest of all arboreal leaf-eaters. To attain this remarkable condition on a diet of eucalyptus leaves, a notoriously poor and somewhat toxic food source, the tree-dwelling marsupials developed unique anatomical and physiological adaptations including specialized chewing and digestive anatomies and a highly sedentary lifestyle. The dramatic differences between the skulls of extinct and modern koalas, especially in the facial region, are probably related to the change to a tougher diet of eucalyptus leaves.

Researchers from the University of New South Wales and the CSIRO have drawn these conclusions after making dozens of detailed anatomical comparisons between the brush-tailed possum, the modern koala and the two fossil species (Litokoala kutjamarpensis and Nimiokoala greystanesi).

The fossil species were unearthed from the Riversleigh World Heritage site in Queensland, Australia. The comparisons reveal similarities in the back of the skull between the modern and fossil koalas, but substantial differences in their teeth, palate and jaws.

Koalas are most closely related among living marsupials to wombats but the two species diverged some 30-40 million years ago. Among fossil koalas there are 18 named species representing five genera spanning the period from the late Oligocene (37 million years ago) to the present.

However, they are generally scarce in the fossil record and most species are only known from a few isolated teeth or jaw fragments. Therefore, it has been difficult to develop an accurate picture of their behaviour, diet and evolution.

The researchers believe that the prehistoric koalas also shared with their modern cousins the ability to produce loud “bellows” based on similar large bony prominences – the auditory bullae – that enclose structures in the middle and inner ear. However the auditory bullae of the extinct Nimiokoala and Litokoala species are not as exaggerated as in the modern koala, according to team member UNSW Professor Mike Archer.

“Modern koalas are extremely sedentary and vocal animals,” says Archer, who is perhaps best known for leading research into the extraordinary Riversleigh fossil deposits in Queensland, which led to the site being listed on the World Heritage Register.

“They produce low frequency vocalisations that pass through vegetation and can be heard up to 800 metres away – far exceeding the home range limits of male koalas. The fossil koalas share similar large bony ear structures to the modern koala and would have been well adapted to detecting vocalisations in the rainforest environment of Riversleigh in the Miocene era.”

“In order to accommodate both the mechanical demands of their new diet, as well as maintaining their auditory sophistication, the koala underwent substantial changes to its cranial anatomy, in particular that of the facial skeleton,” says Dr Julien Louys of UNSW’s School of Biological, Earth and Environmental Sciences. “The unique cranial configuration of the modern koala is therefore the result of accommodating their masticatory adaptations without compromising their auditory system.”

Giant marsupials, reptiles and flightless birds that once roamed Australia became extinct about 40,000 years ago, later than had been thought and some 5,000 years after humans arrived, a new study suggests: here.

A coalition of community environmental groups has been trying to stop logging in the Mumbulla State Forest in the NSW far south east, with a blockade of about 90 people. The forest contains the last known koala colony between Canberra and Victoria: here.

Koalas bellow to attract a mate: here.

June 2010: The reintroduction of 20 red-tailed phascogales into Kojonup Reserve in South-West Australia at the end of last represents another step towards preserving the endangered animal’s future. Twelve females and eight males were released into the reserve as part of the Threatened Fauna Ark Project: here.

Tree kangaroos: here.

Photo of the Day: Diprotodon Tracks, Australia: here.

Paleontologists have unearthed a nearly complete skeleton of a Diprotodon, a fearsome three-ton wombat that rampaged across Australia some 2.5 million years ago until the arrival of the first humans: here.

A STUDY OF ANCIENT kangaroo teeth from south-eastern Queensland suggests that 2.5–5 million years ago, the region was not arid as previously thought: here.

Although Amphicyon is known as the “bear dog,” this prehistoric mammal was directly ancestral to neither bears nor dogs: here.

Fossil piranha teeth discoveries

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From the National Evolutionary Synthesis Center:

New fossil tells how piranhas got their teeth

June 25th, 2009

How did piranhas — the legendary freshwater fish with the razor bite — get their telltale teeth? Researchers from Argentina, the United States and Venezuela have uncovered the jawbone of a striking transitional fossil that sheds light on this question. Named Megapiranha paranensis, this previously unknown fossil fish bridges the evolutionary gap between flesh-eating piranhas and their plant-eating cousins.

Present-day piranhas have a single row of triangular teeth, like the blade on a saw, explained the researchers. But their closest relatives — a group of fishes commonly known as pacus — have two rows of square teeth, presumably for crushing fruits and seeds. “In modern piranhas the teeth are arranged in a single file,” said Wasila Dahdul, a visiting scientist at the National Evolutionary Synthesis Center in North Carolina. “But in the relatives of piranhas — which tend to be herbivorous fishes —the teeth are in two rows,” said Dahdul.

Megapiranha shows an intermediate pattern: it’s teeth are arranged in a zig-zag row. This suggests that the two rows in pacus were compressed to form a single row in piranhas. “It almost looks like the teeth are migrating from the second row into the first row,” said John Lundberg, curator at the Academy of Natural Sciences in Philadelphia and a co-author of the study.

If this is so, Megapiranha may be an intermediate step in the long process that produced the piranha’s distinctive bite. To find out where Megapiranha falls in the evolutionary tree for these fishes, Dahdul examined hundreds of specimens of modern piranhas and their relatives. “What’s cool about this group of fish is their teeth have really distinctive features. A single tooth can tell you a lot about what species it is and what other fishes they’re related to,” said Dahdul. Her phylogenetic analysis confirms their hunch — Megapiranha seems to fit between piranhas and pacus in the fish family tree.

The Megapiranha fossil was originally collected in a riverside cliff in northeastern Argentina in the early 1900s, but remained unstudied until paleontologist Alberto Cione of Argentina’s La Plata Museum rediscovered the startling specimen —an upper jaw with three unusually large and pointed teeth — in the 1980s in a museum drawer.

Cione’s find suggests that Megapiranha lived between 8-10 million years ago in a South American river system known as the Paraná. But you wouldn’t want to meet one today. If the jawbone of this fossil is any indication, Megapiranha was a big fish. By comparing the teeth and jaw to the same bones in present-day species, the researchers estimate that Megapiranha was up to 1 meter (3 feet) in length. That’s at least four times as long as modern piranhas. Although no one is sure what Megapiranha ate, it probably had a diverse diet, said Cione.

Other riddles remain, however. “Piranhas have six teeth, but Megapiranha had seven,” said Dahdul. “So what happened to the seventh tooth?”

“One of the teeth may have been lost,” said Lundberg. “Or two of the original seven may have fused together over evolutionary time. It’s an unanswered question. Maybe someday we’ll find out.”

The team’s findings were published in the June 2009 issue of the Journal of Vertebrate Paleontology.

More information: Cione, A., W. Dahdul, J. Lundberg, and A. Machado-Allison. (2009). “Megapiranha paranensis, a new genus and species of Serrasalmidae (Characiformes, Teleostei) from the upper Miocene of Argentina.” Journal of Vertebrate Paleontology 29(2): 350-358.

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Fossil anglerfish discovered in California, USA

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Linophryne anglerfish

From the Pasadena Star-News in the USA:

Ancient anglerfish fossils discovered at Rosedale

By Bethania Palma, Staff Writer

Article Launched: 04/07/2007

PREHISTORIC: A 15-million-year-old anglerfish fossil was found at the former Monrovia Nursery, which is now the Rosedale housing project.

AZUSA – Scientists this week announced the discovery of a 15-million-year-old anglerfish in land being graded for a housing development.

The fossil was found in the fall by a team of field technicians for Cogstone Resource Management Inc., a company hired by the city to monitor the development site for archaeological and paleontological artifacts and fossils, said Carol Nosches, chief operations officer for Cogstone.

It was found on land of the former Monrovia Nursery, which will become Rosedale, said Bill Holman, vice president of planning and community development for Azusa Land Partners LLC, the project developer.

The remains of the anglerfish is one of only a handful like it in the world, said Gary Takeuchi, curatorial assistant for the department of vertebra[t]e paleontology at the Natural History Museum in Los Angeles.

“It’s extremely rare,” Takeuchi said. “They’re rare because bones are not well glued together, and it’s very easy for them to fall apart.” …

“Sediment had to settle over it very quickly, but no too quickly,” or the fish would have been destroyed by the force.

Sherri Gust, president and lead paleontologist for Cogstone, said the company’s scientists surveyed the area before development began and knew by the sediment deposits there would be fossils there.

“We found lots of fish,” Gust said. “We called it the fish hill.”

Most of them, however, were herrings, in bits and pieces.

Gust said anglerfish, which derive their name from an appendage that serves to lure prey, typically live under 1,000 feet of water.

She explained that when the now-fossilized anglerfish was alive, Southern California were deeply submerged under the Pacific Ocean. …

“I knew immediately what it was,” Takeuchi said, upon identifying the fossil. “I had to calm myself.”

He said less than 20 similar fossils have been found since the 1970s, in Southern California and Europe.

This is not the first time the Rosedale project has unearthed a historic discovery.

In December 2006, hundreds of pieces of prehistoric artifacts were found at what was an ancient village known as Ashuukshanga, where the Tongva/Gabrielino Indians lived.

Devonian fishes in Germany: here.

Hybodus Jurassic shark from Germany: here.

Oldest (Silurian) German fossil fish: here.

Eocene fossil fishes from Messel: here

First fossil mammal found in New Zealand

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This video from the USA says about itself:

Oct 15, 2008

On the Science Channel‘s “Mammals vs. Dinos,” paleontologist Adrian Hunt discovered Adelobasileus, the oldest known mammalian fossil in the Chinle Formation. Adelobasileus is thought to be the common ancestor of mammals and lived 200 million years ago.

From the Australian Broadcasting Corporation:

Ancient Kiwi ‘mouse’ fills fossil gap

Marilyn Head

ABC Science Online

Tuesday, 12 December 2006

Palaeontologists have found remains of one of the most primitive type of land mammal in the world, a mouse-sized creature that’s unlike any mammal alive today.

The find, at the edge of a swampy lake on New Zealand’s South Island, not only fills a gap of the nation’s fossil record, it may also help us understand more about the origin of mammals worldwide.

Researchers, led by Trevor Worthy from Australia’s University of Adelaide, publish their results today online in the Proceedings of the National Academy of Sciences.

Many types of mammals evolved in the Mesozoic period when the dinosaurs dominated, says co-author Alan Tennyson, a palaeontologist from the Museum of New Zealand Te Papa Tongarewa.

But most of those early lineages are now extinct and mammals living today fall into only one of three groups: placentals, marsupials or monotremes.

But this latest find, in sediments deposited 16-19 million years ago, doesn’t fit into any of these groups.

“This is an incredible find. We never expected to find anything like this,” says Tennyson.

“What’s so exciting about this fossil mammal is that it is from one of those ancient lineages that we thought had become extinct much earlier.

This will help us understand more about the origin of mammals worldwide,” he says.

The find is particularly significant for New Zealand as there are virtually no fossils of terrestrial vertebrates between 65 million years ago, when an asteroid impact is thought to have wiped out the dinosaurs, and about 1 million years ago.

In other parts of the world many different mammals evolved to replace dinosaurs as the dominant species.

But in New Zealand the only terrestrial vertebrates that seemed to have evolved were reptiles, frogs, and birds – not mammals.

That’s despite the fact that New Zealand’s landmass separated from Gondwana after many mammals had evolved.

“The suggestion has been that giant birds, like the extinct Haast eagle and the moa, filled the ecological niches that mammals like tigers and grazing animals did elsewhere,” says Tennyson.

“But this is a very primitive mammal and it’s unlikely to have lived here for 60 million years without diversification.

So it opens the possibility that there may be bigger mammals to be found.”

The researchers say the discovery implies the existence of one or more ‘ghost lineages’ and suggests that mammals may have existed on New Zealand more than 125 million years ago.

That may contradict an alternative theory for the lack of fossil evidence for terrestrial mammals: that New Zealand was completely submerged about 25 million years ago and that all of its animals and plants arrived from nearby landmasses.

But the paper suggests that the discovery, along with other Mesozoic survivors such as the lizard-like tuatara and New Zealand’s primitive frogs, confirms that at least some land remained above water throughout the period.

See also here.

And here.

And here.

Kiwi on small New Zealand island: here.

The recently described St Bathans Fauna, from the Manuherikia Group, Early–Middle Miocene, 19–16 Ma, New Zealand, includes six anatid taxa: here.

Australia: digging for dinosaurs and dinosaur age spiny anteater relatives: here.

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