scholarly journals Dental and cranial variation in living Indriidae

Primates ◽  
1979 ◽  
Vol 20 (1) ◽  
pp. 141-159 ◽  
Author(s):  
Philip D. Gingerich ◽  
Alan S. Ryan
Keyword(s):  
Cranial Variation

Cranial variation in Gryposaurus and biostratigraphy of hadrosaurines (Ornithischia: Hadrosauridae) from the Dinosaur Park Formation of Alberta, Canada

2020 ◽  
Vol 57 (6) ◽  
pp. 765-779
Author(s):  
Talia M. Lowi-Merri ◽  
David C. Evans
Keyword(s):  
Morphometric Analysis ◽  
Individual Variation ◽  
Single Species ◽  
Skull Morphology ◽  
Geometric Morphometric ◽  
Cranial Variation ◽  
Short Period ◽  
Alternative Hypotheses ◽  
Geometric Morphometric Analysis ◽  
Dinosaur Park Formation

The Dinosaur Park Formation (Campanian) of Alberta documents one of the most diverse assemblages of hadrosaurine dinosaurs. Historically, two species of the genus Gryposaurus Lambe, 1914 have been recognized in the Dinosaur Park Formation, Gryposaurus notabilis Lambe, 1914 and Gryposaurus incurvimanus Parks, 1919, which are differentiated primarily on their nasal arch morphology. These two species have recently been suggested to represent either variable morphs within G. notabilis (e.g., ontogeny) or two distinct taxa within an evolving Gryposaurus lineage (e.g., anagenesis). These alternative hypotheses have never been adequately tested via detailed morphological comparisons, morphometrics, or biostratigraphy. A geometric morphometric analysis of hadrosaurine skulls from the Dinosaur Park Formation was performed to assess the influence of ontogeny on skull morphology. Gryposaurus incurvimanus skulls were found to be distinctly smaller, and morphologically divergent from those of G. notabilis, with larger G. notabilis skulls having higher nasal arches set farther back on the skull, a size-correlated pattern consistent with ontogenetic nasal retraction documented in other hadrosaurids. Stratigraphic data were used to map this morphology through time, to evaluate the anagenesis hypothesis. The stratigraphic distributions of the two species showed considerable overlap, rejecting anagensis and indicating that the sampled individuals lived over a short period of time (<0.5 Myr). Overall, our results suggest that the hypothesis that G. incurvimanus and G. notabilis represent different ontogenetic stages within a single species cannot be rejected. This study improves our understanding of the extent of potential individual variation within a single Gryposaurus species, which will be useful in assessing the validity of other hadrosaurines.

TAXONOMIC STATUS AND GEOGRAPHICAL CRANIAL VARIATION OF COMMON DOLPHINS (DELPHINUS) IN THE EASTERN NORTH ATLANTIC

2006 ◽  
Vol 22 (3) ◽  
pp. 573-599 ◽  
Author(s):  
Sinead Murphy ◽  
Jerry S. Herman ◽  
Graham J. Pierce ◽  
Emer Rogan ◽  
Andrew C. Kitchener
Keyword(s):  
North Atlantic ◽  
Taxonomic Status ◽  
Cranial Variation ◽  
Eastern North Atlantic ◽  
Common Dolphins

scholarly journals Cranial variation in the European badgerMeles meles(Carnivora, Mustelidae) in Scandinavia

2009 ◽  
Vol 157 (2) ◽  
pp. 433-450 ◽  
Author(s):  
ALEXEI V. ABRAMOV ◽  
ANDREY YU PUZACHENKO ◽  
ØYSTEIN WIIG
Keyword(s):  
Cranial Variation
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