Convergent dental adaptations in pseudo-tribosphenic and tribosphenic mammals

@article{Luo2007ConvergentDA,
  title={Convergent dental adaptations in pseudo-tribosphenic and tribosphenic mammals},
  author={Zhe‐Xi Luo and Qiang Ji and Chong-xi Yuan},
  journal={Nature},
  year={2007},
  volume={450},
  pages={93-97}
}
Tribosphenic molars of basal marsupials and placentals are a major adaptation, with the protocone (pestle) of the upper molar crushing and grinding in the talonid basin (mortar) on the lower molar. [] Key Result Its shoulder girdle and limbs show fossorial features similar to those of mammaliaforms and monotremes, but different compared with those of the earliest-known Laurasian tribosphenic (boreosphenid) mammals. The find reveals a much greater range of dental evolution in Mesozoic mammals than in their…

Evolution of the Tribosphenic Molar Pattern in Early Mammals, with Comments on the “Dual-Origin” Hypothesis

  • Brian M Davis
  • Environmental Science
    Journal of Mammalian Evolution
  • 2011
A series of morphotypes are presented that represent stepwise acquisition of characters of the molar crown, in an effort to clarify homologies and functional analogies among molars of tribosphenic and tribospenic-like mammals, as well as their putative sister groups.

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The Jurassic shuotheriid Pseudotribos shows a great plesiomorphic similarity to monotremes in the structure of the pectoral girdle, with a large interclavicle immovably connected to the clavicle.

Reappraisal of the Tribosphenidan Mammals from the Trinity Group (Aptian—Albian) of Texas and Oklahoma

The taxonomy of the tribosphenidan taxa known from the Trinity Group is updated and the premolar/molar count in each is established with more confidence, identifying strong morphological diversity within this assemblage of stem taxa.

The upper dentition and relationships of the enigmatic Australian Cretaceous mammal Kollikodon ritchiei

Pian, R., Archer, M., Hand, S.J., Beck, R.M.D. and Cody, A. 2016. The upper dentition and relationships of the enigmatic Australian Cretaceous mammal Kollikodon ritchiei. Memoirs of Museum Victoria

Function of pretribosphenic and tribosphenic mammalian molars inferred from 3D animation

This functional study on the teeth of Late Jurassic Dryolestes leiriensis and the living marsupial Monodelphis domestica shows that pretribosphenic and tribosphenIC molars show fundamental differences of food reduction strategies, representing a shift in dental function during the transition of tribospenic mammals.

The stem placental mammal Prokennalestes from the Early Cretaceous of Mongolia

Two Prokennalestes species are regarded as different species rather than sexual morphs of the same species based on rigorous phylogenetic analysis including a large set of known stem therian and stem placental taxa.

Evolution and function of the upper molar talon and its dietary implications in microbats

Results suggest that RFI of both the whole tooth and the trigon varies according to dietary groups, with frugivores having greater crushing function when compared with the other groups, and that the talon is primarily functioning in crushing during food breakdown.

A new mammal skull from the Lower Cretaceous of China with implications for the evolution of obtuse-angled molars and ‘amphilestid’ eutriconodonts

The phylogenetic analyses suggest that Juchilestes is most closely related to the Early Cretaceous Hakusanodon from Japan, in the same Eastern Asiatic geographic region; ‘amphilestids’ are not monophyletic; and eutriconodonts might not be a monophyletsic group, although this hypothesis must be further tested.

Postcranial Skeleton of the Cretaceous Mammal Akidolestes cifellii and Its Locomotor Adaptations

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Tribosphenic Mammals from the Lower Cretaceous Cloverly Formation of Montana and Wyoming

ABSTRACT We report a diverse assemblage of tribosphenidan mammals from several localities in the Cloverly Formation (Lower Cretaceous, Albian) of Montana and Wyoming. This unit is of historical
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