PLOS saw some great paleontological papers published this month. Let’s highlight some of the work that was published in the freely accessible PLOS ONE in September. For a complete and regularly updated list of open access papers being published in dozens of journals, be sure to follow our regularly updated Twitter feed.
Resource partitioning among brachiopods and bivalves at ancient hydrocarbon seeps: A hypothesis
Authors: Steffen Kiel and Jörn Peckmann
In this study published in PLOS ONE, Kiel and Peckmann readdress a long held idea that bivalves outcompeted the once long-dominant brachiopods at hydrocarbon seeps during the Cretaceous. Their study looked at the diversity of both brachiopods and bivalves at the deep-sea hydrocarbon vent deposits throughout the Paleozoic and Mesozoic, and realized that maybe the idea of competition between these two groups is not so cut and dry, and they may not have even impacted each other in the first place.
Redefining species concepts for the Pennsylvanian scissor tooth shark, Edestus
Authors: Leif Tapanila and Jesse Pruitt
From the researchers that redefined our understanding of Helicoprion comes another study looking at unusual extinct sharks with unusual dentition. This time, they are reexamining the shark Edestus from the Late Paleozoic. This taxon has been rampant with over splitting of species for decades, with many new species of these odd sharks based on partial or incomplete tooth whorls (there’s little to no postcranial material associated with these chondrichthyan fossils). Tapanila and Pruitt examined specimens using geometric morphometrics and other techniques, and interestingly found that tooth whorls from Edestus varied from top to bottom jaw and from ontogeny. This paper narrowed the number of species down to a handful, and really clarifies a previously confusing group.
Skull remains of the dinosaur Saturnalia tupiniquim (Late Triassic, Brazil): With comments on the early evolution of sauropodomorph feeding behaviour
Authors: Mario Bronzati, Rodrigo T. Müller, and Max C. Langer
Sauropodomorphs are an important and sometimes understudied group that play an i
mportant role in the early evolution of dinosaurs. This paper, published earlier in September in PLOS ONE looks at one specific Late Triassic sauropodomorph, Saturnalia, that up until know was relatively poorly understood when it came to cranial data. Bronzati et al. examine one of the paratypes of Saturnalia, the only one in the type series to even possess cranial data, using CT scanning technology, and provide a new description of skull material, as well as propose hypotheses regarding feeding behavior and evolution.
The extraordinary osteology and functional morphology of the limbs in Palorchestidae, a family of strange extinct marsupial giants
Authors: Hazel L. Richards, Rod T. Wells, Alistair R. Evans, Erich M. G. Fitzgerald, and Justin W. Adams
Who doesn’t love marsupial megafauna? And in this paper, published mid-September in PLOS ONE, Richards et al. examine a family of marsupials called the Palorchestidae, which lived from the Oligocene to Pleistocene. This group kind of has the opposite of the Saturnalia mentioned above, in that the crania of the of the palorchestids are well-studied (and “tapir-like”) whereas the appendicular anatomy is poorly studied in these taxa. Richards et al. rectify that and propose several diagnostic features based on postcranial anatomy, and suggest some various behaviors for these marsupials based on the unusual forelimbs.
Reconstructing birth in Australopithecus sediba
Authors: Natalie M. Laudicina, Frankee Rodriguez, and Jeremy M. DeSilva
Humans are highly modified for giving birth to large headed babies, but what did our ancestors do with regard to birth mechanics? This study published this month in PLOS ONE by Laudicina et al. examine a recently discovered 1.98 million year old pelvis of Australopithecus to try and understand how this hominin gave birth, and how similar it was to the ways in which humans give birth. This study goes into great detail into modeling the pathway an infant would take while exiting the birth canal, and is a must read if you’re expecting (at least for a little evolutionary perspective).