Category Archives: bones

Air-conditioning in T-Rex’s Head: Thursday, September 5, 2019

Skulls belonging to T-Rexes have always been found with two large holes at the temple. These holes, known as dorsotemporal fenestra (“fenestra” is Latin for “window”), were thought to be sites of jaw muscle attachments. But a recent study has hypothesized that these holes may have had a radically different function: they may have aided in thermal regulation instead for the king of the dinosaurs.

The researchers used thermal imaging on reptiles, specifically alligators, which also have dorsotemporal fenestra. When the temperature outside was cool, and alligators needed to warm up, thermal imaging showed these two large holes get warm. Inversely, when the temperature outside was too hot, thermal imaging showed these two holes become cold, as to keep the alligators cool.

Kent Vilet, one of the study’s authors, comprares the alligators’–and by extension the T-Rex’s– cross-current circulatory system to “an internal thermostat, so to speak.”

Comic by Ryan North, creator of Dinosaur Comics.

This kind of study is a perfect example of how the current analogues of extinct animals can be used to solve anatomical and other paleontological mysteries.

Dinosaurs were warm-blooded reptiles, and a gargantuan creature such as a T-Rex would have generated an immense amount of heat. These two holes would have acted as an “air conditioner” for the skull. It is also hypothesized that T-Rexes may have panted, much like birds, alligators, and dogs do to cool off.

T-Rex action figure shown with replica of a broken T-Rex tooth. Replica by

Since, according to this study, the dorsotemporal fenestra are no longer seen as sites for jaw muscle attachments, it can be concluded that the bite force of a T-Rex may have been smaller than previously assumed.

Information for this post was taken from CNN.

Illustration by Zhao Chuang/Courtesy of PNSO

Skeleton Lake: Thursday, August 22, 2019

Roopkund Lake, which sits atop the Himalayas at 16,500 feet above sea level, is also known as Skeleton Lake and for good but macabre reasons. The lake is frozen most of the year but when it thaws, hundreds of skeletons emerge.

The skeletons were initially discovered by a forest ranger in 1942, who concluded they were invading Japanese soldiers from World War II. But local folklore has a more colorful explanation. There is a nearby shrine for the mountain goddess Nanda Devi. A king and his queen led a pilgrimage with their attendants, but when Nanda Devi saw how raucous they were in their exultant celebratios, she decided to strike them down. A few years ago, a group of archaeologists concluded that the skeletons belonged to a group of travelers from the ninth century who were struck down by a lethal hailstorm, since many of the skulls show blows to the head.

But a new study has yielded even more puzzling results. The skeletons belong to travelers spread over a 1000 years. There are individuals of South Asian origin dating from the 7th to the 10th century. But then, there are individuals of eastern Mediterranean origin–along with an individual of East Asian origin–dating from the 17th to the 20th century. The natural question is: what were individuals from the eastern Mediterranean doing so far from home and why?

One answer is early ecological tourism. Perhaps news of Roopkund Lake had traveled all the way to Europe and some people decided to pay it a visit.

This explanation, however, does not sit well with Kathleen Morrison, chair of the department of anthropology at the University of Pennsylvania. She calls attention to the fact that a Hellenic kingom existed in India for about 200 years, beginning in 180 B.C. She also points out that radiocarbon dating gets less and less accurate the closer we get to the present day, implying that the date between the 17th to the 20th century of the eastern Mediterranean individuals is wrong. To her, this massive amount of skeletons can only mean one thing: it’s a graveyard.

Regardless of whether the site was a massive dumping ground for the dead, the recent study also discovered that the individuals included both children and the elderly, but mysteriously, none were family relatives. To me, this is evidence that the skeletons belong to pilgrims. However, a search for travelogues and written accounts of journeys or pilgrimages has proved unfruitful. And the mystery remains and deepens.

Featured image was taken by Atish Waghwase.

Photograph by Awanish Tirkey.