Triassic Reptile Had ‘Third Eye’

ഒരു മുതലയുടെ അത്ര മാത്രം വലിപ്പം ഉണ്ടായിരുന്ന ഉരഗം ആണ് ട്രൈഒപ്റ്റിക്കസ് , പേര് സൂചിപ്പിക്കുന്ന പോലെ തന്നെ ഇവയുടെ തലയോട്ടിയിൽ കണ്ണ് കുഴിയോട് സാമ്യം ഉള്ള ഒരു ദ്വാരം പാലിയെന്റോളോജിസ്റ്റുകൾ കണ്ടെത്തി .

Paleontologists have described a completely unexpected new species of reptile that lived 230 million years ago (Triassic period).

The ancient reptile has been given the official name Triopticus primus, which means ‘the first of three eyes.’
“From the Latin ‘tri’ (three) and ‘optic’ (vision) for the large opening in the skull roof, resembling a third eye socket. The specific name is from the Latin ‘primus’ (first),” the paleontologists explained.

കൂടുതൽ വായനക്ക് 
http://www.cell.com/current-biology/abstract/S0960-9822(16)30860-0 

Psittacosaurus Used Camouflage, New findings

3D Camouflage in an Ornithischian Dinosaur

Countershading was one of the first proposed mechanisms of camouflage . A dark dorsum and light ventrum counteract the gradient created by illumination from above, obliterating cues to 3D shape . Because the optimal countershading varies strongly with light environment , pigmentation patterns give clues to an animal’s habitat. Indeed, comparative evidence from ungulates shows that interspecific variation in countershading matches predictions: in open habitats, where direct overhead sunshine dominates, a sharp dark-light color transition high up the body is evident; in closed habitats (e.g., under forest canopy), diffuse illumination dominates and a smoother dorsoventral gradation is found. We can apply this approach to extinct animals in which the preservation of fossil melanin allows reconstruction of coloration . Here we present a study of an exceptionally well-preserved specimen of Psittacosaurus sp. from the Chinese Jehol biota . This Psittacosaurus was countershaded with a light underbelly and tail, whereas the chest was more pigmented. Other patterns resemble disruptive camouflage, whereas the chin and jugal bosses on the face appear dark. We projected the color patterns onto an anatomically accurate life-size model in order to assess their function experimentally. The patterns are compared to the predicted optimal countershading from the measured radiance patterns generated on an identical uniform gray model in direct versus diffuse illumination. These studies suggest that Psittacosaurus sp. inhabited a closed habitat such as a forest with a relatively dense canopy.

• •Preserved pigments in the dinosaur Psittacosaurus suggest countershading camouflage
• •We predicted the optimal countershading camouflage for different light environments
• •The dinosaur’s patterns would have been cryptic in a forest, but not open, habitat
• •We can also infer that dinosaur predators used shape-from-shading cues to detect prey

 Model of Psittacosaurus sp. based on skin and pigmentation patterns (specimen from the Senckenberg Museum, Germany). Image credit: Jakob Vinther et al.


Close examination of melanosomes preserved in the specimen of Psittacosaurus preserved with integument indicated that the animal was countershaded, likely due to preferring a habitat in dense forests with little light, much like many modern species of forest-dwelling deer and antelope; stripes and spots on the limbs may represent disruptive coloration. The specimen also had dense clusters of pigment on its shoulders, face (possibly for display), and cloaca (which may have had an antimicrobial function), as well as large patagia on its hind legs that connected to the base of the tail. Its large eyes indicate that it also likely had good vision, which would have been useful in finding food or avoiding predators. The authors were unable to determine which species of Jehol Formation Psittacosaurus the specimen belonged to due to the way the skull is preserved, but ruled out P. mongoliensis, based on hip features.

Credit: 
*cell.com  
*en.wikipedia.com 
* Jakob Vinther et al. 2016. 3D Camouflage in an Ornithischian Dinosaur. Current Biology 26: 1-7; doi: 10.1016/j.cub.2016.06.065

Spinosaurus aegyptiacus

Spinosaurus (meaning "spine lizard") is a genus of theropod dinosaur that lived in what now is North Africa, during the lower Albian to lower Cenomanian stages of the Cretaceous period, about 112 to 97 million years ago. This genus was known first from Egyptian remains discovered in 1912 and described by German paleontologist Ernst Stromer in 1915. The original remains were destroyed in World War II, but additional material has come to light in recent years. It is unclear whether one or two species are represented in the fossils reported in the scientific literature. The best known species is S. aegyptiacus from Egypt, although a potential second species, S. maroccanus, has been recovered from Morocco.


Spinosaurus was among the largest of all known carnivorous dinosaurs, possibly larger than Tyrannosaurus and Giganotosaurus. Estimates published in 2005, 2007, and 2008 suggested that it was between 12.6–18 metres (41–59 ft) in length and 7 to 20.9 tonnes (7.7 to 23.0 short tons) in weight.^[1][2][3] A new estimate published in 2014 and based on a more complete specimen, supported the earlier research, finding that Spinosaurus could reach lengths greater than 15 m (49 ft).^[4] The skull of Spinosaurus was long and narrow, similar to that of a modern crocodilian. Spinosaurus is known to have eaten fish, and most scientists believe that it hunted both terrestrial and aquatic prey; evidence suggests that it lived both on land and in water as a modern crocodilian does. The distinctive spines of Spinosaurus, which were long extensions of the vertebrae, grew to at least 1.65 meters (5.4 ft) long and were likely to have had skin connecting them, forming a sail-like structure, although some authors have suggested that the spines were covered in fat and formed a hump. Multiple functions have been put forward for this structure, including thermoregulation and display.

content credit en.wikipedia.
image credit : Durbed @commons.wikimedia