Mixed models for the relationship between latitude, temperature, and human postcranial form
Bibliographic record
Abstract
Abstract Objectives The global distribution of human body proportions has long been attributed to thermoregulatory adaptation to climate. However, latitude has been the most common proxy for climate across ecogeographic studies. If thermoregulation was driving post‐cranial evolution, temperature should provide a better explanation for the morphological patterns observed than latitude, which encompasses temperature and other variables, as well as major events in human migration history. We investigate relationships between latitude, temperature, and postcranial form by distinguishing the strength of these potential selective factors from population structure. Materials & Methods Quantitative genetic multivariate mixed models were used to estimate morphological effects associated with latitude, minimum temperature, and maximum temperature using osteometric data from 31 globally distributed groups, geographically matched genetic data from 54 groups, and geographically matched temperature data. Results Dimensions reflecting body size (bi‐iliac breadth/femoral head size) show independent evolutionary responses from limb lengths. In models including population history, only dimensions reflecting body size show evidence of response to directional selection. Model results indicate that selection in response to minimum temperature has shaped evolution in body breadth and femoral head size. Models for limb length evolution accounting for population history match results of prior studies, but do not indicate responses to temperature‐driven directional selection. Conclusions This study highlights the importance of considering multiple potential sources of selection within a multivariate evolutionary model, demonstrating the possible synergistic effects of selective pressures. These results complicate the classic thermoregulatory model of human postcranial evolution and show that factors other than temperature may have shaped post‐cranial evolution in humans.
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 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 | 0.001 | 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 | 0.003 | 0.043 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 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; both teacher heads agree on what is shown here.
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".