| Title |
Enamel ultrastructure of fossil and modern pinnipeds: evaluating hypotheses of feeding adaptations in the extinct walrus Pelagiarctos
|
|---|---|
| Published in |
The Science of Nature, May 2016
|
| DOI | 10.1007/s00114-016-1366-z |
| Pubmed ID | |
| Authors |
Carolina Loch, Robert W. Boessenecker, Morgan Churchill, Jules Kieser |
| Abstract |
This study aimed to assess the enamel ultrastructure in modern otariid pinnipeds and in the extinct walrus Pelagiarctos. Teeth of the New Zealand fur seal (Arctocephalus forsteri), sea lion (Phocarctos hookeri), and fossil walrus Pelagiarctos thomasi were embedded, sectioned, etched, and analyzed via scanning electron microscopy. The enamel of NZ otariids and Pelagiarctos was prismatic and moderately thick, measuring 150-450 μm on average. It consisted of transversely oriented Hunter-Schreger bands (HSBs) from the enamel-dentine junction (EDJ) to near the outer surface, where it faded into prismless enamel less than 10 μm thick. The width of HSB was variable and averaged between 6 and 10 prisms, and they presented an undulating course both in longitudinal and cross sections. The overall organization of the enamel was similar in all teeth sampled; however, the enamel was thicker in canines and postcanines than in incisors. The crowns of all teeth sampled were uniformly covered by enamel; however, the grooved incisors lacked an enamel cover on the posterior side of the buccal face. Large tubules and tuft-like structures were seen at the EDJ. HSB enamel as well as tubules and tufts at the EDJ suggest increased occlusal loads during feeding, a biomechanical adaptation to avoid enamel cracking and failure. Despite overall simplification in tooth morphology and reduced mastication, the fossil and modern pinnipeds analyzed here retained the complex undulating HSB structure of other fossils and living Carnivora, while other marine mammals such as cetaceans developed simplified radial enamel. |
X Demographics
The data shown below were collected from the profiles of 11 X users who shared this research output. Click here to find out more about how the information was compiled.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| United States | 3 | 27% |
| Comoros | 1 | 9% |
| United Kingdom | 1 | 9% |
| Australia | 1 | 9% |
| Unknown | 5 | 45% |
Demographic breakdown
| Type | Count | As % |
|---|---|---|
| Members of the public | 7 | 64% |
| Scientists | 4 | 36% |
Mendeley readers
The data shown below were compiled from readership statistics for 34 Mendeley readers of this research output. Click here to see the associated Mendeley record.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| Brazil | 1 | 3% |
| Unknown | 33 | 97% |
Demographic breakdown
| Readers by professional status | Count | As % |
|---|---|---|
| Researcher | 8 | 24% |
| Student > Ph. D. Student | 7 | 21% |
| Student > Master | 5 | 15% |
| Student > Bachelor | 4 | 12% |
| Professor | 2 | 6% |
| Other | 1 | 3% |
| Unknown | 7 | 21% |
| Readers by discipline | Count | As % |
|---|---|---|
| Agricultural and Biological Sciences | 15 | 44% |
| Earth and Planetary Sciences | 6 | 18% |
| Medicine and Dentistry | 2 | 6% |
| Business, Management and Accounting | 1 | 3% |
| Arts and Humanities | 1 | 3% |
| Other | 2 | 6% |
| Unknown | 7 | 21% |
Attention Score in Context
This research output has an Altmetric Attention Score of 116. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 15 December 2022.
All research outputs
#363,806
of 25,543,275 outputs
Outputs from The Science of Nature
#47
of 2,274 outputs
Outputs of similar age
#6,582
of 312,723 outputs
Outputs of similar age from The Science of Nature
#5
of 22 outputs
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