Phylogenetic relationships among megachiropteran species from the two major islands of the Philippines, deduced from DNA sequences of the cytochrome <i>b</i> gene
Bibliographic record
Abstract
Complete cytochrome b gene sequences (1140 base pairs) in species of Megachiroptera were ascertained in order to deduce their phylogenetic relationships, using samples of Cynopterus brachyotis, Eonycteris spelaea, Ptenochirus jagori, Pteropus vampyrus, and Rousettus amplexicaudatus collected from the islands of Luzon and Mindanao in the Philippines. Genetic divergence between samples of R. amplexicaudatus, E. spelaea, and C. brachyotis was very small. On the other hand, a large genetic distance was detected between species of Megachiroptera. The phylogenetic tree using neighbor-joining, parsimony, and maximum-likelihood methods generated similar topologies, reflecting the evolutionary associations among megachiropteran species. We estimated that Megachiroptera separated from Microchiroptera 50.2 million years ago (MYA), and split further approximately 32.4 MYA, forming three lineages: E. spelaea, R. amplexicaudatus, and P. vampyrus and the P. jagori C. brachyotis cluster. The third lineage, composed of P. vampyrus and the P. jagori C. brachyotis cluster, branched out 31.9 MYA. We hypothesize that R. amplexi caudatus diverged from the three members of the subfamily Pteropodinae examined, and its phylogenetic relationship with E. spelaea remains unclear.
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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 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 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".