Asymmetric Hybridization in Cattails (Typha spp.) and Its Implications for the Evolutionary Maintenance of Native Typha latifolia
Bibliographic record
Abstract
Cattails (Typha spp.) have become an increasingly dominant component of wetlands in eastern North America and this dominance is largely attributable to the high frequency of Typha × glauca, the hybrid of native Typha latifolia and putatively introduced Typha angustifolia. Hybridization in this group is asymmetric, with T. angustifolia nearly always the maternal parent of F1 hybrids. However, the magnitude of hybrid infertility and whether mating asymmetries extend to the formation of advanced-generation hybrids have not been examined. We used hand-crosses to measure seed set and germination success. We found that mating asymmetries extend to the formation of back-crosses, with ~0 seeds set when T. latifolia was pollinated by hybrid cattails. Seed set was unaffected by pollen source for T. × glauca or T. angustifolia. However, seed production by T. angustifolia was consistently high while that of T. × glauca was variable and when pollinated by other T. × glauca more than 75% lower than for any other intraspecific cross indicating reduced hybrid fertility. We used these results to parameterize a model of hybrid zone evolution in which mating patterns and fertility were governed by interactions between alleles at nuclear and cytoplasmic loci. The model revealed that asymmetric mating and reduced hybrid fertility should favor the maintenance of T. latifolia over T. angustifolia compared to null expectations. However, the model also indicated restrictive conditions for the long-term maintenance of T. latifolia within populations, indicating that asymmetric mating might only stall rather than prevent the displacement of native cattails by hybrids.
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.
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 | 0.000 | 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".