scholarly journals Response to Comment on “Impacts of the Cretaceous Terrestrial Revolution and KPg Extinction on Mammal Diversification”

Science ◽  
2012 ◽  
Vol 337 (6090) ◽  
pp. 34.2-34 ◽  
Author(s):  
William J. Murphy ◽  
Jan E. Janecka ◽  
Tanja Stadler ◽  
Eduardo Eizirik ◽  
Oliver A. Ryder ◽  
...  
Keyword(s):  
Divergence Times ◽  
Early Eocene ◽  
Cretaceous Terrestrial Revolution

Bininda-Emonds and Purvis reanalyzed our mammalian phylogenetic supermatrix and claim that our results are not significantly different from their delayed-rise hypothesis. We show that our divergence times are ~11 million years later for placental inter- and intraordinal divergences—consistent with a post–Cretaceous-Paleogene (KPg) radiation of most modern mammalian orders—and find no support for the early Eocene delayed-rise hypothesis.

scholarly journals Phylogeny and divergence estimates for the gasteruptiid wasps (Hymenoptera : Evanioidea) reveals a correlation with hosts

2020 ◽  
Author(s):  
Ben A. Parslow ◽  
John T. Jennings ◽  
Michael P. Schwarz ◽  
Mark I. Stevens
Keyword(s):  
Late Jurassic ◽  
Divergence Times ◽  
Evolutionary Relationships ◽  
Taxon Sampling ◽  
Early Eocene ◽  
Molecular Fragments ◽  
Nuclear Markers ◽  
The Family ◽  
Divergence Estimates ◽  
Solitary Bees And Wasps

The Gasteruptiidae are an easily recognised family of wasps whose larvae are considered predator-inquilines in the nests of solitary bees and wasps. There has been minimal molecular research on the family and as a result little understanding of the evolutionary relationships within the group. We present the first molecular phylogeny focused on Gasteruptiidae, generated using three molecular fragments (mitochondrial C01 and nuclear markers EF1-α and 28s) and estimate the divergence times of Evanioidea based on three secondary calibration points. The analyses included 142 specimens of Gasteruptiidae and 5 outgroup taxa from Aulacidae and Evaniidae. The monophyly of the Gasteruptiidae and its subfamilies Gasteruptiinae (Gasteruption) and Hyptiogastrinae (Hyptiogaster and Pseudofoenus) are confirmed. Our results indicate that Evanioidea diverged during the late Jurassic at 151.3 (171.99–136.15)Ma with Evaniidae during the early Cretaceous at 137.33 (140.86–133.67)Ma, and Gasteruptiidae during the Palaeocene at 60.23 (83.78–40.02)Ma. The crown age of Hyptiogastrinae was estimated to be during the mid-Eocene 40.72 (60.9–22.57)Ma and for Gasteruption during the early Eocene at 47.46 (64.7–31.75)Ma, which corresponded to their host divergence ages. We anticipate that more extensive taxon sampling combined with the use of phylogenomic data will help resolve low support within the Gasteruption clade.

Morphology and Affinities of Ampelocissites Seeds (Vitaceae: Ampelopsis clade) from the Paleogene of Texas, USA

2020 ◽  
Vol 45 (3) ◽  
pp. 478-482
Author(s):  
Steven R. Manchester
Keyword(s):  
Computed Tomography ◽  
Cross Sections ◽  
Seed Coat ◽  
Ct Scanning ◽  
Seed Morphology ◽  
Early Eocene ◽  
Micro Computed Tomography ◽  
X Ray ◽  
Fossil Seeds ◽  
Fossil Genus

Abstract—The type material on which the fossil genus name Ampelocissites was established in 1929 has been reexamined with the aid of X-ray micro-computed tomography (μ-CT) scanning and compared with seeds of extant taxa to assess the relationships of these fossils within the grape family, Vitaceae. The specimens were collected from a sandstone of late Paleocene or early Eocene age. Although originally inferred by Berry to be intermediate in morphology between Ampelocissus and Vitis, the newly revealed details of seed morphology indicate that these seeds represent instead the Ampelopsis clade. Digital cross sections show that the seed coat maintains its thickness over the external surfaces, but diminishes quickly in the ventral infolds. This feature, along with the elliptical chalaza and lack of an apical groove, indicate that Ampelocissites lytlensis Berry probably represents Ampelopsis or Nekemias (rather than Ampelocissus or Vitis) and that the generic name Ampelocissites may be useful for fossil seeds with morphology consistent with the Ampelopsis clade that lack sufficient characters to specify placement within one of these extant genera.

An early Eocene florule from central Texas

1925 ◽  
pp. 87-92
Author(s):  
Edward Wilber Berry
Keyword(s):  
Early Eocene ◽  
Central Texas

MAGNETOSTRATIGRAPHY IN THE LODO FORMATION, CA: AN ATTEMPT TO LOCATE HYPERTHERMALS OF THE EARLY EOCENE

2016 ◽  
Author(s):  
Nicole C. Aldrich ◽  
◽  
Christopher J. Pluhar ◽  
Julie A. Rieth ◽  
Samantha J. Gibbs
Keyword(s):  
Early Eocene
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