Ben Creisler
Some recent non-dino papers that may be of interest (to some):
Parental Care, Destabilizing Selection, and the Evolution of Tetrapod Endothermy.
Physiology 35(3): 160-176
doi: https://doi.org/10.1152/physiol.00058.2018
https://journals.physiology.org/doi/full/10.1152/physiol.00058.2018
Parental care has evolved convergently an extraordinary number of times among tetrapods that reproduce terrestrially, suggesting strong positive selection for this behavior in the terrestrial environment. This review speculates that destabilizing selection on parental care, and especially embryo incubation, drove the convergent evolution of many tetrapod traits, including endothermy.
==
Aneila V. C. Hogan, Akinobu Watanabe, Amy M. Balanoff & Gabriel S. Bever (2020)
Comparative growth in the olfactory system of the developing chick with considerations for evolutionary studies.
Journal of Anatomy (advance online publication)
doi: Âhttps://doi.org/10.1111/joa.13197
https://onlinelibrary.wiley.com/doi/10.1111/joa.13197
Despite the longâheld assumption that olfaction plays a relatively minor role in the behavioral ecology of birds, crownâgroup avians exhibit marked phylogenetic variation in the size and form of the olfactory apparatus. As part of a larger effort to better understand the role of olfaction and olfactory tissues in the evolution and development of the avian skull, we present the first quantitative analysis of ontogenetic scaling between olfactory features [olfactory bulbs (OBs) and olfactory turbinates] and neighboring structures (cerebrum, total brain, respiratory turbinates) based on the model organism Gallus gallus. The OB develops under the predictions of a concerted evolutionary model with rapid early growth that is quickly overcome by the longer, sustained growth of the larger cerebrum. A similar pattern is found in the nasal cavity where the morphologically simple (nonâscrolled) olfactory turbinates appear and mature early, with extended growth characterizing the larger and scrolled respiratory turbinates. Pairwise regressions largely recover allometric relationships among the examined structures, with a notable exception being the isometric trajectory of the OB and olfactory turbinate. Their parallel growth suggests a unique regulatory pathway that is likely driven by the morphogenesis of the olfactory nerve, which serves as a structural bridge between the two features. Still, isometry was not necessarily expected given that the olfactory epithelium covers more than just the turbinate. These data illuminate a number of evolutionary hypotheses that, moving forward, should inform tradeoffs and constraints between the olfactory and neighboring systems in the avian head.
============
Comparative growth in the olfactory system of the developing chick with considerations for evolutionary studies.
Journal of Anatomy (advance online publication)
doi: Âhttps://doi.org/10.1111/joa.13197
https://onlinelibrary.wiley.com/doi/10.1111/joa.13197
Despite the longâheld assumption that olfaction plays a relatively minor role in the behavioral ecology of birds, crownâgroup avians exhibit marked phylogenetic variation in the size and form of the olfactory apparatus. As part of a larger effort to better understand the role of olfaction and olfactory tissues in the evolution and development of the avian skull, we present the first quantitative analysis of ontogenetic scaling between olfactory features [olfactory bulbs (OBs) and olfactory turbinates] and neighboring structures (cerebrum, total brain, respiratory turbinates) based on the model organism Gallus gallus. The OB develops under the predictions of a concerted evolutionary model with rapid early growth that is quickly overcome by the longer, sustained growth of the larger cerebrum. A similar pattern is found in the nasal cavity where the morphologically simple (nonâscrolled) olfactory turbinates appear and mature early, with extended growth characterizing the larger and scrolled respiratory turbinates. Pairwise regressions largely recover allometric relationships among the examined structures, with a notable exception being the isometric trajectory of the OB and olfactory turbinate. Their parallel growth suggests a unique regulatory pathway that is likely driven by the morphogenesis of the olfactory nerve, which serves as a structural bridge between the two features. Still, isometry was not necessarily expected given that the olfactory epithelium covers more than just the turbinate. These data illuminate a number of evolutionary hypotheses that, moving forward, should inform tradeoffs and constraints between the olfactory and neighboring systems in the avian head.
============
Free pdf:
Gabriele Sansalone, Silvia Castiglione, Pasquale Raia, Michael Archer, Blake Dickson, Suzanne Hand, Paolo Piras, Antonio Profico and Stephen Wroe (2020)
Decoupling Functional and Morphological Convergence, the Study Case of Fossorial Mammalia.
Frontiers in Earth Science 8: 112.
doi: https://doi.org/10.3389/feart.2020.00112
https://www.frontiersin.org/articles/10.3389/feart.2020.00112/full
Decoupling Functional and Morphological Convergence, the Study Case of Fossorial Mammalia.
Frontiers in Earth Science 8: 112.
doi: https://doi.org/10.3389/feart.2020.00112
https://www.frontiersin.org/articles/10.3389/feart.2020.00112/full
Morphological similarity between biological structures in phylogenetically distant species is usually regarded as evidence of convergent evolution. Yet, phenotypic similarity is not always a sign of natural selection acting on a particular trait, therefore adaptation to similar conditions may fail to generate convergent lineages. Herein we tested whether convergent evolution occurred in the humerus of fossorial mammals, one of the most derived biological structures among mammals. Clades adapting to digging kinematics possess unusual, by mammalian standards, humeral shapes. The application of a new, computationally fast morphological test revealed a single significant instance of convergence pertaining to the Japanese fossorial moles (Mogera) and the North-American fossorial moles (Scalopini). Yet, the pattern only manifests when trade-off performance data (derived from finite element analysis) are added to shape data. This result indicates that fossorial mammals have found multiple solutions to the same adaptive challenge, independently moving around multiple adaptive peaks. This study suggests the importance of accounting for functional trade-off measures when studying morpho-functional convergence. We revealed that fossorial mammals, a classic example of convergent evolution, evolved multiple strategies to exploit the subterranean ecotope, characterized by different functional trade-offs rather than converging toward a single adaptive optimum.
===
Oleg Simakov, Ferdinand MarlÃtaz, Jia-Xing Yue, Brendan OâConnell, Jerry Jenkins, Alexander Brandt, Robert Calef, Che-Huang Tung, Tzu-Kai Huang, Jeremy Schmutz, Nori Satoh, Jr-Kai Yu, Nicholas H. Putnam, Richard E. Green & Daniel S. Rokhsar (2020)
Deeply conserved synteny resolves early events in vertebrate evolution
Nature Ecology & Evolution (2020)
doi: https://doi.org/10.1038/s41559-020-1156-z
https://www.nature.com/articles/s41559-020-1156-z
Deeply conserved synteny resolves early events in vertebrate evolution
Nature Ecology & Evolution (2020)
doi: https://doi.org/10.1038/s41559-020-1156-z
https://www.nature.com/articles/s41559-020-1156-z
Although it is widely believed that early vertebrate evolution was shaped by ancient whole-genome duplications, the number, timing and mechanism of these events remain elusive. Here, we infer the history of vertebrates through genomic comparisons with a new chromosome-scale sequence of the invertebrate chordate amphioxus. We show how the karyotypes of amphioxus and diverse vertebrates are derived from 17 ancestral chordate linkage groups (and 19 ancestral bilaterian groups) by fusion, rearrangement and duplication. We resolve two distinct ancient duplications based on patterns of chromosomal conserved synteny. All extant vertebrates share the first duplication, which occurred in the mid/late Cambrian by autotetraploidization (that is, direct genome doubling). In contrast, the second duplication is found only in jawed vertebrates and occurred in the midâlate Ordovician by allotetraploidization (that is, genome duplication following interspecific hybridization) from two now-extinct progenitors. This complex genomic history parallels the diversification of vertebrate lineages in the fossil record.
News:
=====
Brenen M. Wynd, David G. Demar JR. & Gregory P.Wilson (2020)
Euselachian diversity through the uppermost Cretaceous Hell Creek Formation of Garfield County, Montana, USA, with implications for the Cretaceous-Paleogene mass extinction in freshwater environments.
Cretaceous Research 104483 (advance online publication)
https://doi.org/10.1016/j.cretres.2020.104483
https://www.sciencedirect.com/science/article/pii/S0195667120301695
Temporal changes in the diversity of euselachians (e.g., sharks and rays) across the Cretaceous-Paleogene (K-Pg) boundary are not well understood, particularly from freshwater ecosystems. Here, we quantitatively analyze euselachian diversity during the last ca. 2 Ma of the Cretaceous using 1,518 teeth from 40 vertebrate microfossil localities within the nonmarine facies of the Hell Creek Formation, northeastern Montana, USA. We identify 10 euselachians including one hybodont, five orectolobiforms, one lamniform, one sclerorhynchiform, and two rajiforms. Among these, two are novel and described herein. Diversity metrics reveal an increase in species richness and heterogeneity from the lower to middle portions of the Hell Creek Formation. Thereafter, diversity remained elevated and stable with no turnover until ~5 m below the K-Pg boundary. Above this horizon, including the last ~50 kyr of the Cretaceous, raw species richnesses dropped precipitously, and all euselachians (except possibly Myledaphus) went locally extinct across the boundary. Preceding this drop in richness, changes in euselachian community structure occurred, including steady declines in the relative abundances of M. pustulosus. These patterns do not support regression of the Western Interior Seaway as the single proximal cause of euselachian extinctions across the K-Pg boundary. Rather, euselachian local extinctions likely were the result of the multiple environmental perturbations occurring just before (volcanism, climate change) and at the K-Pg boundary (bolide impact). This high-resolution temporal pattern of euselachian diversity adds to those from other local taxa (e.g., mammals, lissamphibians) to present a more complex view of the K-Pg mass extinction of the continental biota.