| Title |
Microanatomy and life history in Palaeopleurosaurus (Rhynchocephalia: Pleurosauridae) from the Early Jurassic of Germany
|
|---|---|
| Published in |
The Science of Nature, December 2016
|
| DOI | 10.1007/s00114-016-1427-3 |
| Pubmed ID | |
| Authors |
Nicole Klein, Torsten M. Scheyer |
| Abstract |
The tuatara (Sphenodon punctatus) from New Zealand is often-erroneously-identified as a 'living fossil', although it is the lone survivor of a large, successful radiation of Rhynchocephalia, sister taxon to squamates (lizards and snakes), that thrived through the Mesozoic and Cenozoic and experienced an intricate evolution of life histories and feeding habits. Within Rhynchocephalia, only Pleurosauridae are thought to be marine and piscivorous. Here, we present bone histological data of the Jurassic pleurosaurid Palaeopleurosaurus, showing osteosclerosis (i.e. bone mass increase) in its gastralia, and some osteosclerosis in its rib but no increase in bone mass in the femur, supporting a gradual skeletal specialization for an aquatic way of life. Similar to Sphenodon, the bone tissue deposited in Palaeopleurosaurus is lamellar zonal bone. The femoral growth pattern in Palaeopleurosaurus differs from that of terrestrial Sphenodon in a more irregular spacing of growth marks and deposition of non-annual (i.e. non-continuous) rest lines, indicating strong dependency on exogenous factors. The annual growth mark count in adult but not yet fully grown Palaeopleurosaurus is much lower when compared to adult individuals of Sphenodon, which could indicate a lower lifespan for Palaeopleurosaurus. Whereas the gastral ribs of Palaeopleurosaurus and Sphenodon are similar in composition, the ribs of Sphenodon differ profoundly in being separated into a proximal tubular rib part with a thick cortex, and an elliptical, flared ventral part characterised by extremely thin cortical bone. The latter argues against a previously inferred protective function of the ventral rib parts for the vulnerable viscera in Sphenodon. |
X Demographics
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Geographical breakdown
| Country | Count | As % |
|---|---|---|
| Unknown | 1 | 100% |
Demographic breakdown
| Type | Count | As % |
|---|---|---|
| Members of the public | 1 | 100% |
Mendeley readers
The data shown below were compiled from readership statistics for 20 Mendeley readers of this research output. Click here to see the associated Mendeley record.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| Unknown | 20 | 100% |
Demographic breakdown
| Readers by professional status | Count | As % |
|---|---|---|
| Student > Ph. D. Student | 5 | 25% |
| Researcher | 3 | 15% |
| Professor | 2 | 10% |
| Student > Master | 2 | 10% |
| Student > Doctoral Student | 2 | 10% |
| Other | 0 | 0% |
| Unknown | 6 | 30% |
| Readers by discipline | Count | As % |
|---|---|---|
| Earth and Planetary Sciences | 8 | 40% |
| Agricultural and Biological Sciences | 5 | 25% |
| Environmental Science | 1 | 5% |
| Unknown | 6 | 30% |
Attention Score in Context
This research output has an Altmetric Attention Score of 4. 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 10 April 2023.
All research outputs
#7,145,757
of 23,794,258 outputs
Outputs from The Science of Nature
#739
of 2,195 outputs
Outputs of similar age
#128,264
of 424,838 outputs
Outputs of similar age from The Science of Nature
#7
of 11 outputs
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