The oldest higher true crabs (<scp>C</scp>rustacea: <scp>D</scp>ecapoda: <scp>B</scp>rachyura): insights from the <scp>E</scp>arly <scp>C</scp>retaceous of the <scp>A</scp>mericas
Why this work is in the frame
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Bibliographic record
Abstract
Abstract Despite the extensive fossil record of higher crabs ( E ubrachyura) from L ate C retaceous and C enozoic rocks worldwide, their E arly C retaceous occurrences are scarce and fragmentary, obscuring our understanding of their early evolution. Until now, representatives of only two families of eubrachyuran‐like crabs were known from the E arly C retaceous: C omponocancridae and Tepexicarcinidae fam. nov., both monospecific lineages from the Albian (~110–100 Ma) of North and Central America, respectively. The discovery of T elamonocarcinus antiquus sp. nov. (Telamonocarcinidae) from the early A lbian of C olombia, S outh A merica (~110 Ma), increases to three the number of known E arly C retaceous eubrachyuran‐like families. The ages and geographical distributions of the oldest eubrachyuran‐like taxa (i.e. C omponocancridae, T elamonocarcinidae and T epexicarcinidae fam. nov.) suggest that the oldest higher true crabs might have originated in the A mericas; that they were already morphologically diverse by the late E arly C retaceous; and that their most recent common ancestor must be rooted in the E arly C retaceous, or even the L ate J urassic.
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.
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.004 | 0.028 |
| Meta-epidemiology (narrow) | 0.004 | 0.002 |
| Meta-epidemiology (broad) | 0.004 | 0.002 |
| Bibliometrics | 0.001 | 0.003 |
| Science and technology studies | 0.005 | 0.010 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.008 | 0.004 |
| Research integrity | 0.004 | 0.005 |
| Insufficient payload (model declined to judge) | 0.000 | 0.007 |
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 it