Mittwoch, 21. Mai 2008

The Tasmanian Wolf lives! (...at least in part)

Australian zoologist have successfully inserted DNA of the since 1936 (assumed) extinct Tasmanian Wolf (Thylacinus cynocephalus) in mouse (Mus musculus) embryos. The inserted genes are" still working" and control the development of cartilagenous and bones .
PASK et al. (2008): Resurrection of DNA Function In Vivo from an Extinct Genome. PLoS ONE 3(5): e2240.

Donnerstag, 15. Mai 2008

Meet the mighty mammoth

Trying to find something to post about "Meeting a prehistoric creature" for the 20#Boneyard, I was wondering, where can we today meet a animal that no longer exist?

Most animals during earth history became extinct, and with them the ecosystems, that they roamed, are going forever. Maybe, but even in our daily wor(k)ld sometimes we can get a glimps on a prehistoric beast - for example simply by trying to send a letter. The first rappresentation on a stamp from a prehistoric mammal appared in Cuba in 1958, in memory of the centenary of the birth of the naturalist Carlos de la Torre de la Huerta. The stamp showed a giant ground sloth of the genus Megalocnus. Today prehistoric beasts are quiet a common and beautiful motif for a stamp.


A very prominent Behemoth in the collectiv imagination is surely the wolly mammoth (Mammuthus primigenius). Some authors even claim that the name derived from the arabian word "mehemot", and passed trough the jewish "behemoth" until the verses of Job. The Mammoth is also a rare example of extinct animals that possess lots of generic names - the siberian indigenous claimed it "cheli", "uukyla" or "maimant", and interpreted it as a giant rat or mole, guardian of the land of the underground or deads.

We know very much about this animal, not only by fossils or mumificated bodys, found in the siberian permafrost, but we even have the opportunity to observe ancient (10-12.000 B.C.) pictures of it, like in the cave of Rouffignac, in the district Dordogne (Central-France) - and the displayed animals look much better and realistic than a certain recent movie.


What´s the meaning of this art we ignore (and I´m not talking about the movie), but seeing it, we remain affascinated of the naturalistic rappresentation of the animals in display. During the romanian and greek civilitation, and later until the medieval times, the fossils of this prehistoric elephant played an important role in myths and legends of remains from giants and dragons, found in the quaternary deposits of Europe.

Even the first "scientific" reconstruction of an presumed extinct animals shows, at least in part, a mammoth. In 1663 the german naturalist Otto Von Guericke tried to reconstruct the "unicornum verum", the true unicorn, from parts of various pleistocene mammals - the teeths remarkably seems to be the big, striped molars of a Mammoth, even if the skull and the rest of the skeleton is probabily from a wolly rhinoceros. This historic picture is rappresentet in nearby every book about history of the paleontological disciplines.



The true nature of this bones were recongnised in the year 1799, when the Mammoth got´s his scientific name.


Today, every greater Museum for Natural History has or tries to display a Mammoth-skeleton, or at least the typical molar (the picture shows a fossil found in a gravelpit from South Germany) of this animal, in fact, no true museum can be without a trophy of the mighty Mammoth, so the Museum for Natural History in Prague, even if it´s seem they have taken the word "trophy" much to serious.


As a private collector, you can buy not only a complete skeleton, but even mumified skin or fur. So you can claim to possess a carpet from true Mammoth - if you can get the special offer and pay 8.500 Dollars - so last year on the fossil exhibition of Munich! Much of this fossil material is coming in the last years from the russian, and especially siberian territory, from the melting permafrost are emerging tons and tons of fossil bones.


But enough of classic fossils, more cheap, and more cute are surely two merchandising Mammoths in love, or rappresent this picture two males involved in a furious combat? Probabily not, because driving in a car with figthing Mammoths on board can be to dangerous, and so taking photos of them would be difficult, and I would not succeed to take this rare document of ethological behavior.

Anyway, you can inconter the mammoth in todays world in various places (ecosystems?) and different situations, not only in books, but even guarding books...


...on plastic bags (in honor of one of the most complete and biggest skeleton of a Mammoth in Central Europa)...


...or more classic, on a T-shirt...


So, you see, it is not hard to meet prehistoric beast, but to avoid it...



Sonntag, 4. Mai 2008

Mammals Blogosphere

The Boneyard XIX is on air, and hostet by Nick Gardner on his brandnew BLOG Familiarity Breeds Content he offers us also some mammal-related news and thoughts.
Searchers after horror haunt strange, far places (H. P. Lovecraft) - so it is not surprising that Michele Whisenhunt is following the footsteps of Dimetrodon in the Permian of Texas - terrifing ancestor of the mammals, which had both mammal and reptile characteristics. Going on, Darren Naish, discuss how "grandma" Lucy maked the first, or at least most important, step to bipedal gait, and why we can´t expect to see an elephant using the same kind of locomotion, even it is a dwarf elephant or a modified amphibian. Thanks to Lucy even the painfull "knuckle-walking" is for us a thing of the past (...maybe).
Brian Switek has celebrated Caturdays, presenting the perfect, terrifying predator of the future. And don´t forget the birthday of (the other) Huxley, in this case we are speaking about "Darwin's Bulldog". Just reaching the goal is the second Mammalthon with a clear 1. place, and because today only the best counts, meet and fear the superpredator - Thylacoleo, from Australia.
Last, but not least, to even accomplain the dark side of the mammal in us - here the story of an inusual behavior of a sexually frustrated fur seal, and a new study provided the exact timing when we finally get this nasty dinosaurs out of the way to rule the world !! ... why is that pigeon looking at me?

The next Boneyard will be hosted on Laelaps, 18.05 - so paleomammologist rise and write, rise... and write...

Donnerstag, 1. Mai 2008

The strange (evolutionary) story of Hoplitomeryx

The italian fossil record of terrestrial mammals is relatively poor during the Early and Middle Miocene. It is only in the Late Miocene that the record of terrestrial vertebrates increases. The pre-Messinian, Late Miocene, land mammal localities of Italy document the existence of at last three distinct bioprovinces. Two of the latter are characterised by faunas with manifestly endemic features, denominated after the recent geographical regions the Abruzzi-Apulia and the Tusco-Sardinian paleobioprovince. The third, the Calabro-Sicily bioprovince, shows mainly non-endemic mammals with elements and connections to north Africa.

During the Miocene and the Early Pliocene changing sea level transformed the area of the Italian peninsula for certain periods in an archipelago with isolated islands of various sizes and a humid and warm climate – an ideal playground for evolution. One of these today lost islands was the modern peninsula of Gargano on the east coast of South Italy, separated from the main land by a branch of the Adriatic Sea. Practically all mammals of Gargano show extraordinary morphological signs of insularity. This faunal assemblage is called Mikrotia-fauna, after the common genus of the endemic murid of the region.

Paleogeografic reconstruction of the italian peninsula during the Miocene-Pliocene transition. Green rappresents land, in brown the first highlands. Dots marks the discussed localities.

An extraordinary fossil from this fauna found of the locality near the city of Foggia were the remains of a before unknown small artiodactyl – the new established genus Hoplitomeryx (LEINDERS 1984). This small deer or deer-like animal not only showed five horns –a pair of horns above each orbit and one central nasal horn- but also prominent sabrelike ('moschid' type) upper canines.


Skull of Hoplitomeryx matthei, after VAN DER GEER


A unique combination of anatomically diagnostic characters (with still some specialisation in the structure of the limbs). Today the Barking Deers (Muntiacinae) from the Indonesian archipelago, seen as basal cervids, still displays the upper canines, but possess antlers, non horns.

But the features seen in Hoplitomeryx maybe are representing only parallel evolved characters, letting the phylogenetic and systematic position still uncertain. Today only one species is described, Hoplitomeryx matthei (LEINDERS 1984) in a own family, Hoplitomerycidae, even if the fossil material of Gargano shows almost four to five distinct “size-classes” (from estimated 5 to 50kg body mass), that maybe represent single species (VAN DER GEER 2007). If this are really species, the uniform anatomical characters seen on all the fossil material, let´s assume, that a rapid adaptation and radiation from an common ancestor to the diverse habitats on the island succeeded.

The fossils of Hoplitomeryx were found in the late sixties and subsequent years in reworked reddish, massive or crudely stratified silty-sandy clays (terra rossa), which partially fill the paleo-karstic fissures in the Mesozoic limestone substrate and that are on their turn overlain by Late-Pliocene-Early Pleistocene sediments of a subsequently marine, shallow water and terrigenous origin. The exact age is uncertain, the stratigraphic correlation and the mammal chronology let assume a temporal range from at least the late Miocene to early Pliocene, with preferences from various authors to the Pliocene (VAN DER GEER 2007).

Until 1990 Hoplitomeryx was thought as endemic element of the former island of Gargano, but in 1990, a Miocene deposit with a rich assemblage of fossil vertebrates (crocodiles, turtles, various deers and an otterlike-creature) was discovered on the eastern ridge of the Mount Civita (Scontrone, Abruzzo) and excavated by the Museum of Paleontology and Geology of the University of Florence. Found encapsulated in crushed yellow limestone, the fossils were deposited approximately 12 million years ago. Seven mammalian species were recognized, one of them with references to the Hoplitomeryx.
This maybe indicates a paleogeographic connection, maybe trough landbrige or smaller islands, or a temporal connection with the european mainland.

By the Messinian (7Ma) all taxa of the Tusco-sardinian bioprovince disappeared and were replaced by a continental fauna with clear European affinities (BONFIGLIO 2005). This geological period is marked by a pronounced sea level drop of the Mediterranean, causing deposition of thousand of meters of evaporites. The former isolated islands get reconnected with the Europeean continent, and a dramatic faunal turnover occured.
Only remnants of the Abruzzi-Apulia paleobioprovince survived this dramatic episode until the Pliocene, but with the establishment of the tectonic rised landbrige from the promontory of Gargano to the Italian peninsula, the last Hoplitomeryx got extinct.



Miocene-Pliocene succession at Eraclea-Minoa, Sicily.


BONFIGLIO, L. (2005): Paleontologia dei vertebrati in Italia – Evoluzione biologica, significato ambientale e paleogeografia.

VAN DER GEER, A. (2007): The effect of insularity on the Eastern Mediterranean early cervoid Hoplitomeryx. The study of the forelimb. Quaternary International.

Sonntag, 27. April 2008

(Paleo) Mammals Online