Fossil evidence of the avian vocal organ from the Mesozoic

Nature ◽  
2016 ◽  
Vol 538 (7626) ◽  
pp. 502-505 ◽  
Author(s):  
Julia A. Clarke ◽  
Sankar Chatterjee ◽  
Zhiheng Li ◽  
Tobias Riede ◽  
Federico Agnolin ◽  
...  
Keyword(s):  
1984 ◽  
Vol 11 (3) ◽  
pp. 395-413 ◽  
Author(s):  
ADRIAN DESMOND

SUMMARY R. E. Grant's advocacy of transmutation is considered in relation to the scientific climate of the 1850s. To understand the palaeontological framework of his development theory, the unpublished “Palaeozoology” lectures, delivered in 1853–7, are analysed and his sources tabulated. The lectures are shown to contain the following additional themes: (1) a refutation of Lyell's steady-state geology, (2) support for serial development, (3) use of metamorphic effacement to explain the lack of pre-Silurian fossils, and (4) nebular hypothesis. The difficulty of supporting serial development using fossil evidence at this late date is discussed, and this difficulty is deemed to have contributed to the failure of Grant's theory of species “generation”.


2011 ◽  
Vol 68 (4) ◽  
pp. 379-392 ◽  
Author(s):  
Katerina Harvati
Keyword(s):  

Paleobiology ◽  
2011 ◽  
Vol 37 (2) ◽  
pp. 195-213 ◽  
Author(s):  
Taylor S. Feild ◽  
Garland R. Upchurch ◽  
David S. Chatelet ◽  
Timothy J. Brodribb ◽  
Kunsiri C. Grubbs ◽  
...  

The photosynthetic gas exchange capacities of early angiosperms remain enigmatic. Nevertheless, many hypotheses about the causes of early angiosperm success and how angiosperms influenced Mesozoic ecosystem function hinge on understanding the maximum capacity for early angiosperm metabolism. We applied structure-functional analyses of leaf veins and stomatal pore geometry to determine the hydraulic and diffusive gas exchange capacities of Early Cretaceous fossil leaves. All of the late Aptian—early Albian angiosperms measured possessed low vein density and low maximal stomatal pore area, indicating low leaf gas exchange capacities in comparison to modern ecologically dominant angiosperms. Gas exchange capacities for Early Cretaceous angiosperms were equivalent or lower than ferns and gymnosperms. Fossil leaf taxa from Aptian to Paleocene sediments previously identified as putative stem-lineages to Austrobaileyales and Chloranthales had the same gas exchange capacities and possibly leaf water relations of their living relatives. Our results provide fossil evidence for the hypothesis that high leaf gas exchange capacity is a derived feature of later angiosperm evolution. In addition, the leaf gas exchange functions of austrobaileyoid and chloranthoid fossils support the hypothesis that comparative research on the biology of living basal angiosperm lineages reveals genuine signals of Early Cretaceous angiosperm ecophysiology.


Palaios ◽  
2010 ◽  
Vol 25 (4) ◽  
pp. 269-273 ◽  
Author(s):  
F. MUNIZ ◽  
J. M. DE GIBERT ◽  
R. ESPERANTE
Keyword(s):  

PLoS ONE ◽  
2015 ◽  
Vol 10 (9) ◽  
pp. e0138544 ◽  
Author(s):  
Yi-Ming Cui ◽  
Bin Sun ◽  
Hai-Feng Wang ◽  
David Kay Ferguson ◽  
Yu-Fei Wang ◽  
...  

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