A molecular phylogenetic study of two relict species of melanopline grasshoppers
Bibliographic record
Abstract
Two species belonging to the large grasshopper genus Melanoplus, Melanoplus gaspesiensis and Melanoplus madeleineae, are thought to have survived in refugia in eastern Canada during the Wisconsin glaciation period and perhaps during earlier glacial episodes as well. It has been proposed that either Melanoplus borealis, which is widely distributed today, or its antecedent gave rise to the two relict species. Our research, based on standard phylogenetic analyses of mitochondrial sequences, examines this claim by establishing the positions of M. gaspesiensis and M. madeleineae within Melanoplus. There is a very close and strongly supported connection between M. madeleineae and M. borealis (d = 1.36%), whereas M. gaspesiensis is more distant from the latter (d = 2.08%) and appears closely aligned with two other species. Molecular clock estimates of the times of separation of M. madeleineae and M. gaspesiensis from M. borealis are 0.68 and 1.04 million years ago, respectively. Within-species diversities of 1.01 and 0.70% for M. madeleineae and M. gaspesiensis, respectively, are of comparable magnitudes to that of the continentally distributed Melanoplus sanguinipes (0.86%), clearly indicating that neither species endured bottleneck effects despite isolation.
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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".