Category Archives: #365papers

#365papers for April 15, 2017

Toldeo, Bargo, Vizcaino, Iuliis, and Pujos, 2017, Evolution of body size in anteaters and sloths (Xenarthra, Pilosa): phylogeny, metabolism, diet and substrate preferences: Earth and Environmental Science Transaction of the Royal Society of Edinburgh, v. 106, p. 289-301.

What’s it about?

Modern sloths are tiny, tree-dwelling herbivores that dangle below the branches and move very, very slowly. However, in the past, there were enormous sloths that ranged across the landscape.

This paper discusses both anteaters and sloths, the modern components of which have adaptations for eating diets of low nutrition. The fossil record of both closely related groups are studied, and the relationships between great size and inferred metabolic rate and diets are considered.Continue reading “Body Size, Metabolic Rate, and Body Temperature in Giant Sloth Evolution – #365papers – 2017 – 105”

#365papers for April 14, 2017

Clemens, 2017, Procerberus (Cimolestidae, Mammalia) from the latest Cretaceous and earliest Paleocene of the northern western interior, USA: Paleobios, v. 34.

What’s it about?

Procerberus is a genus of mammal that lived mostly just after the extinction of the dinosaurs. There is some confusion about the distinctions among the several species of Procerberus and the relationship of this genus to other groups of mammals. This paper is about sorting that all out.Continue reading “Who (or What) is Procerberus – #365papers – 2017 – 104”

#365papers for April 13, 2017

Ibiricu, Lamanna, Martinez, Casal, Cerda, Martinez, and Salgado, 2017, A novel form of postrcranial skeletal pneumaticity in a sauropod dinosaur: Implications for the paleobiology of Rebbachisauridae: Acta Palaeontologica Polonica.

What’s it about?

In birds, dinosaurs, and some other archosaurs (includes crocodilians) there are often hollow spaces in bones that are connected to the respiratory system. The hollowness of bones is called pneumaticity. The authors here describe the bones of a recently described species Katepensaurus goicoecheai. Katepensaurus shows a style of pneumaticity that is not seen in any other dinosaurs.Continue reading “Air Sacs and Uniquely Hollow Bones in a New Sauropod – #365papers – 2017 – 103”

#365papers for April 12, 2017

Araujo, Fernandez, Polcyn, Frobisch, and Martins, 2017, Aspects of gorgonopsian paleobiology and evolution: insights from the basicranium, occiput, osseous labyrinth, vasculature, and neuroanatomy: PeerJ 5:e3119; DOI:10.7717/peerj.3119

What’s it about?

Gorgonopsians were land-dwelling vertebrates that existed early on along the lineage that eventually gave rise to mammals and to us. They did not yet possess classically mammalian features, in particular the structure of the middle ear, but they did share in common with us a skull shape called synapsidy. This feature distinguishes all mammals and their ancestors from other ‘reptiles’ like dinosaurs, lizards, snakes, and turtles, as well as birds.

The authors of this paper used Propagation Phase Contrast Synchrotron Radiation-based micro-Computed Tomography (a technique a little like a CAT-scan or an MRI) to examine two fossil gorgonopsian skulls. With this method, they were able to essentially take apart the bones of the skull and study their relationships. They were also able to look at the shape of the brain itself, as well as determining where the major blood vessels went and examine the structure of the inner ear.Continue reading “Skulls and Brains of Early Mammalian Ancestors – #365papers – 2017 – 102”

#365papers for April 11, 2017

Stocker, Zhao, Nesbitt, Wu, and Li, 2017, A short-snouted, Middle Triassic phytosaur and its implications for the morphological evolution and biogeography of Phytosauria: Nature Scientific Reports, 7:46028, DOI:10.1038/srep46028

What’s it about?

Phytosaurs are crocodile-looking marine reptiles from the Miocene. They are unique in having a long snout with the nares (nose openings) on the top of the skull, rather than on the tip of the snout. Here, a new phytosaur is described that has a short snout and the nares aren’t on the top of the head. It’s definitely a phytosaur due to other diagnostic skeletal features of the skull and limbs, and appears to represent an early stage of evolution where the characteristic snout and nostril position are not yet developed.Continue reading “Before Long Snouts: An Early Phytosaur – #365papers – 2017 – 101”

#365papers for April 10, 2017 — The 100th paper for 2017!

Reid, Garcia-Bellindo, Payne, Runnegar, and Gehling, 2017, Possible evidence of primary succession in a juvenile-dominated Ediacara fossil surface from the Flinders Ranges, South Australia: Palaeogeography, Palaeoclimatology, Palaeoecology, v. 476, p. 68-76.

What’s it about?

The oldest fossils of multicellular organisms on Earth come from the Ediacara biota (575-541 million years ago). Such fossils are found globally, but were first described from the Flinders Ranges of South Australia.

The authors here describe a new locality in the Flinders Ranges that have many well-preserved Ediacaran fossils. Most of these fossils are smaller than the same species found at other localities. There is also an unexpected dominance of one species, Dickinsonia. This combined evidence suggests that this locality preserves an ecosystem that was developing not long after some environmental catastrophe. Thus, this is a primary successional fauna.Continue reading “After the Disaster: Ecological Succession 555 Million Years Ago – #365papers – 2017 – 100”