Finding Characters that will Differentiate Six Very Similar Packera (Ragwort) Taxa in the Upper Midwest
Bibliographic record
Abstract
The North American plant genus Packera is a member of the Asteraceae (Sunflower Family). Most of the approximately 70 Packera species are morphologically distinct and occur in different geographic areas or microhabitats. However populations of the widespread, P. paupercula complex are variable in morphology, chromosome number, and ecological requirements. One undescribed group of tetraploid populations currently recognized in P. paupercula occurs in the Upper Midwest and Canada, including northern Minnesota. These “Northern Tetraploids” may merit recognition at the species or varietal level. Northern Tetraploids are very similar in morphology to other diploid members of the P. paupercula complex in our region (varieties paupercula, savannarum, and pseudomentosa) and to P. plattensis a tetraploid prairie species found in western Minnesota. As part of a larger study that seeks to describe and classify the Northern Tetraploids, I measured 13 characters on 82 herbarium specimens that include these six Packera taxa. I used one way Analysis of Variance (ANOVA) to determine which characters best differentiate the taxa. While no one character will differentiate among all taxa, mean flowering date, involucre length, ray length, and ratios derived from basal leaf measurements were significantly different in some pairwise comparisons. Used in combination, these characters will provide useful information for biologists attempting to identify these taxa in the field. Furthermore, naming a new species or variety requires valid publication that includes a thorough morphological description and a key to related species.
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How this classification was reachedexpand
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 | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.001 | 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 teacher head, 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".