Tag Archives: Reptiles

The true Colour of Mosasaurs and Ichthyosaurs

Now we know the true colours (I had hoped for something a bit more exciting perhaps

Skin pigmentation provides evidence of convergent melanism in extinct marine reptiles

http://www.nature.com/nature/journal/vaop/ncurrent/full/nature12899.html

Nice reconstructions here:

http://www.sci-news.com/paleontology/science-color-mosasaurs-ichthyosaurs-turtles-1672.html

__________________________________
Laura

New Captorhinid Reptile Found in China

A new captorhinid reptile, Gansurhinus qingtoushanensis, gen. et sp. nov., was found from Xidagou Formation (Middle Permian) at Qingtoushan (Dashankou) locality near Yumen, Gansu Province, and from Naobaogou Formation (Late Permian) in Baotou, Nei Mongol, China, as reported in the recent issue of Naturwissenschaften 98 (435–441), 2011. The find provides new evidence for further studies on the evoluting and paleogeography of captorhinid reptiles.

http://english.ivpp.cas.cn/rh/rp/201105/t20110523_70125.html


Majid

Toothache in Permian reptile

In popular news:

http://news.discovery.com/animals/ancient-reptile-toothache-110418.html

The actual paper:

Osteomyelitis in a Paleozoic reptile: ancient evidence for bacterial infection and its evolutionary significance

Robert R. Reisz & Diane M. Scott & Bruce R. Pynn & Sean P. Modesto, Naturwissenschaften DOI 10.1007/s00114-011-0792-1

We report on dental and mandibular pathology in Labidosaurus hamatus, a 275 million-year-old terrestrial reptile from North America and associate it with bacterial infection in an organism that is characterized by reduced tooth replacement. Analysis of the surface and internal mandibular structure using mechanical and CT-scanning techniques permits the reconstruction of events that led to the pathology and the possible death of the individual. The infection probably occurred as a result of prolonged exposure of the dental pulp cavity to oral bacteria, and this exposure was caused by injury to the tooth in an animal that is characterized by reduced tooth replacement cycles. In these early reptiles, the reduction in tooth replacement is an evolutionary innovation associated with strong implantation and increased oral processing. The dental abscess observed in L. hamatus, the oldest known infection in a terrestrial vertebrate, provides clear evidence of the ancient associa- tion between terrestrial vertebrates and their oral bacteria.

-Laura

Stop the Press! – Homaeothermic Marine Reptiles

All,

Old news, new research, enjoy!

Review:

Ryosuke Motani: Warm-Blooded "Sea Dragons"?
Science 11 June 2010: 1361-1362
http://www.sciencemag.org/cgi/content/full/328/5984/1361

Article:

Aurélien Bernard, Christophe Lécuyer, Peggy Vincent, Romain Amiot,
Nathalie Bardet,Eric Buffetaut, Gilles Cuny, François Fourel,
François Martineau, Jean-Michel Mazin, Abel Prieur: Regulation of
Body Temperature by Some Mesozoic Marine Reptiles
http://www.sciencemag.org/cgi/content/full/328/5984/1379

Abstract: "What the body temperature and thermoregulation processes
of extinct vertebrates were are central questions for understanding
their ecology and evolution. The thermophysiologic status of the great
marine reptiles is still unknown, even though some studies have suggested
that thermoregulation may have contributed to their exceptional
evolutionary success as apex predators of Mesozoic aquatic ecosystems.
We tested the thermal status of ichthyosaurs, plesiosaurs, and mosasaurs
by comparing the oxygen isotope compositions of their tooth phosphate to
those of coexisting fish. Data distribution reveals that these large
marine reptiles were able to maintain a constant and high body
temperature in oceanic environments ranging from tropical to cold
temperate. Their estimated body temperatures, in the range from 35° ± 2°C
to 39° ± 2°C, suggest high metabolic rates required for predation and 
fast swimming over large distances offshore."

--Mikko