Varieties of<i>Melampyrum lineare</i>(Orobanchaceae) Revisited
Bibliographic record
Abstract
Patterns of morphological variation within the North American annual hemiparasite, Melampyrum lineare, are reexamined in this study of its four varieties: M. lineare var. americanum, M. lineare var. latifolium, M. lineare var. lineare, and M. lineare var. pectinatum. Data were collected from 248 herbarium specimens drawn from the species' geographic range in Canada and the United States and included 45 vegetative, reproductive, and ecological characters. Each variety was found to have a broader distribution than previously reported, which expanded the area of known sympatry among the varieties to include most of the species' range. Multivariate analysis of variance revealed statistically significant differences in morphology among the four varieties (p<0.001 in all cases). However, linear discriminant analysis of morphological data showed a continuum of variation and accurately identified the taxonomic variety of individual specimens only 44–75% of the time. Moreover, principal component analysis of continuous morphological variables failed to uncover partitions of the data that would support alternative circumscriptions of subspecific taxa. A chi-squared contingency test to determine if varietal determinations depended on soil-moisture level failed to find evidence supporting such a conclusion (p=0.121). Results show that morphological variation observed in this species cannot be divided into reliably diagnosable groups. While ecotypes are common in Eurasian Melampyrum species and are explained in part by seasonal variation, no common garden experiments to determine how abiotic and biotic conditions affect phenotype have been conducted using M. lineare. Ongoing molecular phylogeographic study of this species may provide alternative metrics for characterizing the diversity of this wide-ranging species.
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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 | 0.001 |
| 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".