Dinosaurs were hardcore! The carnivores were ferocious and even the herbivores were armed with brutal defensive weaponry. For example, triceratops’ horns, or ankylosaurus’ tail club, and now the newly discovered Bajadasaurus pronuspinax with their long, thin, sharp porcupine-esque spines. Their funky mohawk like protection would have made any meat-eater think twice before taking a bite.
Paleontologist Pablo Gallina and his colleagues recently unearthed this creature from a bed of 139-million-year-old rock in northern Patagonia, Argentina. It is from the species sauropods, or “lizard-footed” dinosaurs, which have long necks, long tails, small heads, four enormous weight-bearing legs, and they are impressively large. It would have roamed the Earth around 140 million years ago, between the early to mid-Jurassic and early Cretaceous periods.
Their paper published in the journal Nature calls the dorsal appendages “extremely elongate bifid cervical neural spines that point permanently forward,” which is why they named the dinosaur Bajadasaurus pronuspinax: Bajada, in reference to the location of discovery; pronus, Latin for bent over forward; and spinax, Greek for spine.
The fossils they found included only one of the cervical vertebra, along with a nearly complete skull (including a “dermal roof and palatal bones, a braincase, and a nearly complete lower jaw”).
Although it wasn’t much, it was enough for the paleontologists to extrapolate the presence of a whole row of spines arming the length of the head and neck. From this discovery they were able to conclude that the Bajadasaurus belongs to a group of sauropods called Dicraeosaurids, distinguished by this unusual punk-rocker morphology.
The scientists have some theories as to what purpose the Dicraeosaurids’ dramatic ornamentation served. Here are a few:
- A support structure for a thermoregulatory sail
- A padded crest for display
- A dorsal hump acting as fat reservoir
- As inner cores for dorsal horns
There were a few other courtship and defensive adaptations. They believe it is very likely that these spikes served more than one of these functions. It is also possible that they would vary slightly between specimens, depending on a whole range of environmental and social factors.
Although one speculation is prevalent – the fact that the structure is so delicate and extremely elongated, strongly suggests that the role of these spikes are not as a weapon, but as a warning. That warning being something along the lines of, “Hey T-Rex, my neck is bristling with spikes, which will not taste good and will hurt your face a lot.”
“We believe that the long, pointed spines – extremely long and thin – on the neck and back of Bajadasaurus should serve to deter potential predators. However, we think that if they were only bare bone structures or covered only with skin they could have broken or fractured easily with a blow or when attacked by other animals. This leads us to suggest that these spines should have been protected by a corneal keratin sheath similar to what happens in the horns of many mammals.”
Another observation that makes sense is that, because the eye sockets are near the top of the head, (which allowed the eyes to see around and above them) they know that Bajadasaurus spent much of its time grazing the ground. This could explain the direction of the spines: as it bent down, the spines would protect the dinosaur’s head and vulnerable long neck from being snapped or bitten.
Of course, for now this is all speculation. So, maybe while these scientists search for more fossils of this new dinosaur, other researchers could study todays animals with similar features. Charles Darwin once said, “Whilst this planet has gone cycling on…endless forms most beautiful and most wonderful have been, and are being, evolved.” In other words, the answer to why these Sauropods had scary bony mohawks millions of years ago could be amongst us now, in some modern, evolved version of the species!