The early fossil history of Salicaceae: a brief review

1992 ◽  
Vol 98 ◽  
pp. 155-167 ◽  
Author(s):  
Margaret E. Collinson
Keyword(s):  
North America ◽  
Current Evidence ◽  
Early Eocene ◽  
Leafy Shoot ◽  
History Of ◽  
Riparian Habitats

SynopsisCurrent evidence for early fossil Salicaceae is summarised. Most data come from Europe and North America where revisionary studies are in progress in several laboratories. The earliest records of the modern genera are from North America with Populus section Abaso in the Late Palaeocene and Salix subgenus Salix in the early Eocene. This evidence is based mainly on leaves but the presence of Populus is confirmed by a leafy shoot with attached fruiting raceme. The two genera first occur later in Europe with Populus in the uppermost Eocene and Salix in the Middle Oligocene. Members of both genera in both continents apparently occupied riparian habitats early in their history.

The Tempo and mode(S) of Prebiotic Evolution

1997 ◽  
Vol 161 ◽  
pp. 419-429 ◽  
Author(s):  
Antonio Lazcano
Keyword(s):  
Origin Of Life ◽  
Organic Compounds ◽  
Biological Evolution ◽  
Current Evidence ◽  
Early Diversification ◽  
Time Period ◽  
The Galaxy ◽  
History Of ◽  
Widespread Phenomenon ◽  
The Origin Of Life

AbstractDifferent current ideas on the origin of life are critically examined. Comparison of the now fashionable FeS/H2S pyrite-based autotrophic theory of the origin of life with the heterotrophic viewpoint suggest that the later is still the most fertile explanation for the emergence of life. However, the theory of chemical evolution and heterotrophic origins of life requires major updating, which should include the abandonment of the idea that the appearance of life was a slow process involving billions of years. Stability of organic compounds and the genetics of bacteria suggest that the origin and early diversification of life took place in a time period of the order of 10 million years. Current evidence suggest that the abiotic synthesis of organic compounds may be a widespread phenomenon in the Galaxy and may have a deterministic nature. However, the history of the biosphere does not exhibits any obvious trend towards greater complexity or «higher» forms of life. Therefore, the role of contingency in biological evolution should not be understimated in the discussions of the possibilities of life in the Universe.

Identity of the oribatid mite Oribata curva and transfer to Trichogalumna (Acari, Oribatida, Galumnidae), with discussion of nomenclatural and biogeographical issues in the ‘curva’ species-group

Zootaxa ◽  
2017 ◽  
Vol 4272 (4) ◽  
pp. 551
Author(s):  
ROY A. NORTON ◽  
SERGEY G. ERMILOV
Keyword(s):  
North America ◽  
Oribatid Mite ◽  
Species Group ◽  
Type Material ◽  
Similar Species ◽  
History Of ◽  
Molecular Assessment

Based on the study of type material, other historical specimens, and new collections, the adult of the thelytokous oribatid mite Oribata curva Ewing, 1907 (Galumnidae) is redescribed and the name is recombined to Trichogalumna curva (Ewing, 1907) comb. nov. A confusing history of synonymies and misidentifications is traced in detail, and their effect on published statements about biogeography is assessed. Reliable records of T. curva are only those from North America. The tropical mite Pergalumna ventralis (Willmann, 1932) is not a subspecies of T. curva. The widely-reported Trichogalumna nipponica (Aoki, 1966) and other similar species form a complex with T. curva that needs further morphological and molecular assessment. 

scholarly journals I.—History of the Names Cambrian and Silurian in Geology

1873 ◽  
Vol 10 (111) ◽  
pp. 385-395 ◽  
Author(s):  
T. Sterry Hunt
Keyword(s):  
Great Britain ◽  
North America ◽  
Upper Cambrian ◽  
History Of ◽  
Lower Palaeozoic ◽  
The Subject

It is proposed in the following pages to give a concise account of the progress of investigation of the lower Palæozoic rocks during the last forty years. The subject may naturally be divided into three parts: 1. The history of Silurian and Upper Cambrian in Great Britain from 1831 to 1854; 2. That of the still more ancient Palæozoic rocks in Scandinavia, Bohemia, and Great Britain up to the present time, including the recognition by Barrande of the so-called primordial Palæozoic; fauna; 3. The history of the lower Palæozoic rocks of North America.

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