Late Ordovician geographic patterns of extinction compared with simulations of astrophysical ionizing radiation damage [PDF]
Paleobiology 35, 311-320 (2009), 2008 Based on the intensity and rates of various kinds of intense ionizing radiation events such as supernovae and gamma-ray bursts, it is likely that the Earth has been subjected to one or extinction level events during the Phanerozoic. These induce changes in atmospheric chemistry so that the level of Solar ultraviolet-B radiation reaching the surface and
arxiv
Power, competition, and the nature of history [PDF]
, 2019 Historians have debated whether pathways and events from the past to the present are influenced largely by contingency, the dependence of outcomes on particular prior conditions, or whether there is long-term emergent directional change.
Vermeij, Geerat J
core +1 more source
Paleoneuroanatomy of the European lambeosaurine dinosaur Arenysaurus ardevoli [PDF]
, 2015 The neuroanatomy of hadrosaurid dinosaurs is well known from North America and Asia. In Europe only a few cranial remains have been recovered that include the braincase. Arenysaurus is the first European endocast for which the paleoneuroanatomy has been
Canudo, JI +3 more
core +9 more sources
The case for dynamic subsidence of the U.S. east coast since the Eocene [PDF]
, 2008 The dynamic subsidence of the United States east coast is addressed using the discrepancy between regional and global estimates of sea level, elevation of paleoshorelines, and adjoint models of mantle convection that assimilate plate motions and seismic ...
Gurnis, Michael +3 more
core +1 more source
Analysis of periodicity of extinction using the 2012 geological time scale [PDF]
Paleobiology 40, 177-196 (2014), 2013 Analysis of two independent data sets with increased taxonomic resolution (genera rather than families) using the revised 2012 time scale reveals that an extinction periodicity first detected by Raup and Sepkoski (1984) for only the post-Paleozoic actually runs through the entire Phanerozoic.
arxiv
Concept for a research project in early crustal genesis [PDF]
Planetary volatiles, physical and chemical planetary evolution, surface processes, planetary formation, metallogenesis, crustal features and their development, tectonics, and paleobiology are ...
Ashwal, L., Phillips, R. J.
core +1 more source
Using the Fossil Record to Evaluate Timetree Timescales. [PDF]
, 2019 The fossil and geologic records provide the primary data used to established absolute timescales for timetrees. For the paleontological evaluation of proposed timetree timescales, and for node-based methods for constructing timetrees, the fossil record ...
Marshall, Charles R
core
Evidence of strong stabilizing effects on the evolution of boreoeutherian (Mammalia) dental proportions. [PDF]
, 2019 The dentition is an extremely important organ in mammals with variation in timing and sequence of eruption, crown morphology, and tooth size enabling a range of behavioral, dietary, and functional adaptations across the class.
Archibald J. D. +26 more
core +5 more sources
Thriving at high hydrostatic pressure: the example of ammonoids (extinct cephalopods) [PDF]
arXiv, 2006 Ammonoids are a group of extinct mollusks belonging to the same class of the living genus Nautilus (Cephalopoda). In both Nautili and ammonoids, the (usually planospiral) shell is divided into chambers separated by septa that during the lifetime were filled with gas at atmospheric pressure.
arxiv
Possible Origin of Stagnation and Variability of Earth's Biodiversity
, 2014 The magnitude and variability of Earth's biodiversity have puzzled scientists ever since paleontologic fossil databases became available. We identify and study a model of interdependent species where both endogenous and exogenous impacts determine the ...
Geisel, Theo +2 more
core +1 more source