Functional diversity of North American broad‐leaved trees is codetermined by past and current environmental factors
Bibliographic record
Abstract
Abstract Modern and historical climate are known to codetermine broad‐scale species richness and composition patterns in temperate regions. Nonetheless, is poorly understood the extent to which these effects individually or in combination determine functional diversity, many studies have simply assumed equilibrium between current climate and functional diversity. We estimated functional richness (FRich) and dispersion (FDisp) of North American broad‐leaved trees by combining distribution and trait information. Then, we determined if contemporary water‐energy availability, current topographic variability, historical climatic stability, and lagged immigration from glacial refugia co‐determined the functional diversity of North American broad‐leaved trees. We did this by assessing the directionality, magnitude, and relative importance of various contemporary and historical environmental factors know to affect species diversity. Contrasts were performed across all North America (Mexico, United States, and Canada), and areas within this region that were glaciated or ice‐free during the Last Glacial Maximum (~21 000 yr ago). FRich and FDisp showed distinct geographic patterns that are strongly associated with both contemporary environmental conditions and glacial–interglacial climate change. Model averaged regression coefficients and AIC‐based variable relative importance estimates show that contemporary productivity (FRich‐wAIC: 1.0; FDisp‐wAIC: 1.0), annual precipitation (FRich‐wAIC: 0.81; FDisp‐wAIC: 1.0), and accessibility to glacial refugia (FRich‐wAIC: 0.92; FDisp‐wAIC: 1.0) have the strongest associations to FRich and FDisp. Furthermore, the association of functional diversity with topographic heterogeneity showed steeper slopes in ice‐free regions. These findings suggest that, contrary to the expectation climate‐diversity equilibrium, functional diversity of North America broad‐leaved trees is codetermined by current climate and lagged immigration from glacial refugia.
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 | 0.001 |
| 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".