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Journal Article Summary



Perezmoreno, B.P.,Sanz, J.L., Buscalioni, A.D., Moratalla, J.J., Ortega, F., 
Rasskingutman, D. "A unique multitoothed ornithomimosaur dinosaur from the 
Lower Cretaceous of Spain" Nature, August 4, 1994, 370, 6488, 363-367.
The Lower Cretaceous lithographic limestones from Las Hoyas (province of 
Cuenca, Spain) have yielded important vertebrate fossil remains. We report 
here a new specimen, the first ornithomimosaur theropod found in Europe. 
Pelecanimimus polyodon gen. et sp. nov., has some striking elements 
preserved, such as the hyoid, sternum and integumentary impressions. The 
fossil has revealed other unexpected features, including a derived hand in 
an ancient ornithomimosaur, and a large number of teeth (over 200) with a 
distinctive morphology. This specimen suggests an alternative evolutionary 
process towards the toothless condition in Omithomimosauria, which could be 
explained by an exaptation. Pelecanimimus polyodon stresses the relationship 
between Troodontidae and Ornithomimosauria."

This article is not exactly dinosaurian, however, being an ecologist by 
training I think a discussion of the Cretaceous plants and climate have a 
direct bearing on dinosaurs. They were, after all, in-situ.

Srivastava, S.K., "Evolution of Cretaceous Phytogeoprovinces, Continents and 
Climates" Review of Palaeobotany and Palynology, July 1994, 82, 3-4, 
197-224.
A phytogeoprovince is defined as an isolated landmass with its 
characteristic flora. Modem pollen depositional patterns indicate that 
pollen produced on a landmass are transported mostly by water and deposited 
on landmass edges under various ecological conditions. Preserved pollen 
assemblages can be recovered and used to recognize past phytogeoprovinces, 
continents, and their climates. Such a model is used here to interpret the 
evolution of Cretaceous phytogeoprovinces and their climates. Jurassic 
continents remained in close proximity, devoid of major elevations and 
inland seas, until the Neocomian. Jurassic flora, fauna, and climates were 
cosmopolitan globally. Cretaceous phytogeoprovinces evolved from the two 
Jurassic ones, namely a boreal Cerebropollenites and an austral 
Microcachryidites phytogeoprovince separated by the Tethys. The creation of 
a third phytogeoprovince during the Neocomian, by the appearance of 
Dicheiropollis in the equatorial region, coincided with the initial rift of 
South America and Africa and the opening of the Labrador Sea. An extensive 
Neocomian marine regression exposed large landmasses. Except for a warm 
temperate climate in the boreal-most province, a subtropical to tropical 
climate prevailed globally during the Neocomian. The opening of the South 
Atlantic separated South America and Africa completely by the end of the 
Albian. Except in northern Siberia, the Aptian-Albian interval was a 
transgressive marine phase which inundated landmasses and created inland 
seas. A progressive cooling trend had set in the Aptian climate. After 
reaching a minimum in the late Aptian, the climate started warming up in the 
Albian. An elater-bearing flora replaced the equatorial Dicheiropollis flora 
in the Aptian-Albian. The Cenomanian was a cool phase in the Cretaceous, the 
Coniacian-Santonian a little warmer, and the Maastrichtian a little cooler 
again. During the Late Cretaceous, active continental movement displaced 
landmasses whereas marine transgressions created new inland seas separating 
the land areas. Climates were differentiated latitudinally. The early 
Cenomanian appearance of Normapolles pollen in the Urals area initiated the 
development of one of the boreal provinces which became discrete in the 
Senonian. Similarly, the other boreal Aquilapollenites phytogeoprovince was 
established during Turonian-early Maastrichtian time. These two boreal 
provinces were separated longitudinally by N-S epeiric seas in North America 
and the Urals area. A palmate Constantinisporis flora replaced the 
elater-bearing flora of the equatorial phytogeoprovince in the Senonian. An 
austral province was established by the appearance of Nothofagus flora in 
the Coniacian. The integrity of the Late Cretaceous boreal and equatorial 
phytogeoprovinces was destroyed by the late Maastrichtian marine regression 
by exposing land connections across provinces and allowing land-plant 
migration interprovincially. The austral phytogeoprovince remained isolated 
and its proteaceous and Nothofagus floras of the Late Cretaceous have 
survived up to the present.