We all know that crocodiles are reptiles with long snouts, conical teeth, strong jaws and long tails. But according to researchers at Stony Brook University in New York, we don’t know what we thought we knew.
Rather, some crocodiles possessed a dazzling array of adaptations that resulted in unique and sometimes bizarre anatomy, including blunt, pug-nosed snouts, pudgy bodies and short tails.
These anatomical adaptations of the incredibly diverse group of reptiles called notosuchian crocodyliforms are brilliantly illuminated in a new Memoir of the Society of Vertebrate Paleontology. This massive, richly illustrated volume, edited by Drs. David W. Krause and Nathan J. Kley of Stony Brook, clearly dispels the notion that crocodiles are static, unchanging “living fossils.”
The volume, which gives an account of fossil crocodyliform anatomy that is unprecedented in its thoroughness, is set for publication on December 8, 2010.
The epitome of crocodyliform anomaly is represented by Simosuchus clarki, which lived in Madagascar at the end of the “Age of Dinosaurs” (about 66 million years ago). First described preliminarily in 2000 from a well-preserved skull and partial skeleton, Simosuchus shattered the crocodyliform mold with its blunt snout, leaf-shaped teeth, and short, tank-like body covered in a suit of bony armor.
“ Simosuchus is easily the most bizarre crocodyliform ever found,” declared Dr. Christopher Brochu, a leading expert on fossil crocodiles from the University of Iowa.
Over the next decade, expeditions to Madagascar recovered more skulls and skeletons, now representing nearly every bone of Simosuchus. A reconstruction of this uncommonly complete fossil reptile and an interpretation of its place in the crocodile evolutionary tree became the subject of the new volume.
“The completeness and preservation of the specimens demanded detailed treatment,” said Krause, Distinguished Service Professor in the Department of Anatomical Sciences at Stony Brook University. “It just seemed unconscionable to not document such fantastic fossil material of this unique animal.”
Brochu, who did not participate in the research, said that “very few crocodilians – even those alive today – have been subjected to this level of analysis. This reference sets a new standard for analyses of extinct crocodyliforms and is going to used for decades.”
A separate chapter of the monograph is devoted to each of the major parts of the animal – skull, backbone, limbs, and armor.
“The skull and lower jaw in particular are preserved almost completely,” said Kley, assistant professor in the Department of Anatomical Sciences at Stony Brook University. “This, combined with high-resolution CT scans of the most exquisitely preserved specimen, has allowed us to describe the structure of the head skeleton – both externally and internally – in exceptional detail, including even the pathways of the tiniest nerves and blood vessels.”
But while it is easy to lose one-self in the details of these incredible fossils, one of the most amazing features is the overall shape of the animal. Two feet long, pudgy, with a blunt snout and the shortest tail of any known crocodyliform, Simosuchus was not equipped to snatch unsuspecting animal prey from the water’s edge as many modern crocodiles do.
“Simosuchus lived on land, and its crouched posture and wide body probably meant it was not very agile or fast,” said Joseph Sertich, a Ph.D. student in the Department of Anatomical Sciences at Stony Brook who participated in the research.
In addition, its short, under-slung jaw and weak, leaf-shaped teeth show that it probably munched on a diet of plants. While the idea of a gentle, vegetarian crocodile is unusual to us today, the new memoir makes it easy to imagine Simosuchus ambling through its semi-arid grassland habitat, pausing to nip at plants and crouching low to hide from predators like the meat-eating dinosaur Majungasaurus.
The paleontologists also found evidence that pointed to the evolutionary origin of Simosuchus. “Interestingly, an analysis of evolutionary relationships suggests Simosuchus’ closest relative lived much earlier, in Egypt,” said Sertich.
Details like these are crucial to deciphering the pattern of the dispersal of life around the globe, an area of scientific study known as biogeography. Whatever its ancestry, Simosuchus has set a surprising new standard for what constitutes a crocodile.
The article appears in the Journal of Vertebrate Paleontology 30(6, Supplement) published by Taylor and Francis.ABOUT THE SOCIETY OF VERTEBRATE PALEONTOLOGY
Citation: D. W. Krause and N. J. Kley (eds.), Simosuchus clarki (Crocodyliformes: Notosuchia) from the Late Cretaceous of Madagascar. Society of Vertebrate Paleontology Memoir 10. Journal of Vertebrate Paleontology 30(6, Supplement).
Journal Web site: Society of Vertebrate Paleontology: http://www.vertpaleo.org
| Newswise Science News
Cells communicate in a dynamic code
19.02.2018 | California Institute of Technology
Studying mitosis' structure to understand the inside of cancer cells
19.02.2018 | Biophysical Society
For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.
In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...
Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale
Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...
For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.
But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...
Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.
The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...
Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters
Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...
15.02.2018 | Event News
13.02.2018 | Event News
12.02.2018 | Event News
19.02.2018 | Materials Sciences
19.02.2018 | Materials Sciences
19.02.2018 | Life Sciences