The Late Permian herbivore <i>Suminia</i> and the early evolution of arboreality in terrestrial vertebrate ecosystems
Bibliographic record
Abstract
Vertebrates have repeatedly filled and partitioned the terrestrial ecosystem, and have been able to occupy new, previously unexplored habitats throughout their history on land. The arboreal ecospace is particularly important in vertebrate evolution because it provides new food resources and protection from large ground-dwelling predators. We investigated the skeletal anatomy of the Late Permian (approx. 260 Ma) herbivorous synapsid Suminia getmanovi and performed a morphometric analysis of the phalangeal proportions of a great variety of extant and extinct terrestrial and arboreal tetrapods to discern locomotor function and habitat preference in fossil taxa, with special reference to Suminia. The postcranial anatomy of Suminia provides the earliest skeletal evidence for prehensile abilities and arboreality in vertebrates, as indicated by its elongate limbs, intrinsic phalangeal proportions, a divergent first digit and potentially prehensile tail. The morphometric analysis further suggests a differentiation between grasping and clinging morphotypes among arboreal vertebrates, the former displaying elongated proximal phalanges and the latter showing an elongation of the penultimate phalanges. The fossil assemblage that includes Suminia demonstrates that arboreality and resource partitioning occurred shortly after the initial establishment of the modern type of terrestrial vertebrate ecosystems, with a large number of primary consumers and few top predators.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".