For all those who follow this series, I'm going to be moving my diary post date from Wednesday to Tuesday--the Saturday diary will only be periodic. Academics chew a hole in my free time!
Contrary to the depiction in Jurassic Park, paleontologists almost never find a skeleton articulated. As we see in the wilds today, the world of ancient ages past was one that was none too kind to the skeleton of a dead animal. Scavengers would see the corpse rotting away and score a meal, dragging off the bones every which way; a torrent of rain crashes and moves the bones apart, potentially burying them in mud (and giving the bones the chance to fossilize). Only very rarely do you see a whole skeleton in place--primarily during catastrophic events like a flash flood or a collapsed muddy sand dune.
Because of this, we often only have partial (and disarticulated) material to work with when determining the pathways evolution has taken. And sometimes, the partial material becomes something of an enigma.
1. Amphicoelias fragillimus
One of the first (and in my opinion, most extreme) examples of this takes us back over 100 years ago, during the great feuds that took place between Edward Cope and Othniel Marsh, a pair of brilliant and highly jealous and protective paleontologists. The two did everything they could to deceive and take advantage of the other's paleontological career--Marsh would frequently send spies after Cope, in search of any kind of scientific wrongdoing or mistake to capitalize on.
The pair gathered mountains of material during these so called Bone Wars. One bone in particular, an absolutely enormous neural arch (the process placed directly on top of the centrum or base of the vertebrae) discovered by Cope in what is now thought to be the Morrison Formation (strata piled down during the Late Jurassic period) is a new level of titanic.
The measurements given are astounding--1500 mm from the base of the neural spine to the top. Scaling up to full size, that's a vertebrae around 2.7 meters (about 8.9 feet) tall. A close relation between the tallest dorsal vertebrae (those that contain the ribs of the main body--just behind the cervical or neck vertebrae and in front of the sacral or hip vertebrae) and the size of the femur gives an estimate of 4.3-4.6 meters (14.1-15.1 feet). Extrapolating this, depending on the actual body proportions, Amphicoelias fragillimus has been estimated at 190 feet in length.
(Amphicoelias fragillimus featured in A with a human/Diplodocus for scale)
What happened to the remains is still somewhat unclear, but Cope wrote of the great lengths required to move the fossil, and at the time the preservatives used in the field were not yet invented (Marsh began to use chemical stabilizers in 1880), so it's thought to be likely that the fossil was destroyed after it was drawn and described.
2. Deinocheirus mirificus
In the 1970s, a joint Mongolian-Polish expedition was sent into the deserts of the Gobi to help uncover some of its fantastic fossils (the Fighting Dinosaurs, described in previous diaries was uncovered by one of these expeditions). One such journey revealed something so enormous that it still blows my mind (though it would probably astound me even more were I to see them up close, which eventually I hope to do--a cast can be found at the American Museum of Natural History in New York).
The owner of these giant forelimbs is still relatively unknown, but it's thought that they may belong to a basal (an animal displaying primitive features of its respective group--much like the Platypus) Ornithomimosaur, commonly called 'Ostrich Dinosaurs' due to the fact that well... they look like dinosaurian ostriches (non-avian ostriches anyway; ostriches already lay claim to being dinosaurs).
3. Spinosaurus aegypticus
Ernst Stromer, a German paleontologist who lead several expeditions into the Egyptian desert in the early 1900s was the sole discoverer of several absolutely fascinating dinosaurs--the several times prior mentioned Carcharodontosaurus and a bizarre animal by the name of Spinosaurus.
Spinosaurus (previously diaried about here) is the youngest (and largest--estimates place it at 16-18 meters/52-59 feet, though that's subject to change with much of the body unknown) known member of the Spinosauridae, a fascinating group of bipedal largely piscivorous (fish-eating) theropod dinosaurs characterized by a very elongate thin snout and a massive hand claw ('manual ungual'), both of which are almost certainly adaptations utilized for their piscivorous diet.
Though several discoveries have helped helped us paint a somewhat clearer picture of the animal (including a partial frontmost portion of the cranium, or upper portion of the skull), most of the material (which included the unique dorsal vertebrae and a portion of the dentary, or lower jaw) was destroyed during an allied air raid on the German city of Munich in 1944.
With luck, future discoveries will help paint a clearer picture of this fascinating animal.
Enjoy!