Performance, Sex, and Phenotypic Evolution in Insular and Continental Anole Lizards
Bibliographic record
Abstract
Sexual dimorphism is an important component of biodiversity and has long been a subject of interest to biologists. In many groups of organisms, the sexes differ in size, and the evolution of such differences – called sexual size dimorphism (SSD) – has been widely studied. However, much less attention has been given to the evolution of shape and performance dimorphism, even though differences in these phenotypic attributes can tell us much about the contrasting selective pressures that act on the sexes. In this thesis I test whether macroevolutionary patterns of sexual dimorphism in size, shape, and performance support hypotheses based on population-level natural and sexual selection. To this end, I studied the Anolis radiation, a highly species-rich group of neotropical lizards. This group represents an ideal system to test such hypotheses due to its remarkable ecological and morphological diversity, its widespread distribution, and its evolutionary diversity in both size and shape dimorphism. In Chapter 1, I show that size and shape follow allometric patterns of dimorphism (i.e., Rensch’s Rule) as a result of the differential effects of a climatic gradient on male and female size across populations of A. carolinensis. In Chapter 2, I use size, shape, and bite force data from a large sample of Anolis species to show that SSD is strongly linked to dimorphism in biting performance, as expected if sexual selection on male fighting ability drove size evolution in the group. I also show that insular and continental anoles differ in biting performance, even after accounting for size, and that this difference may in part be due to the evolution relatively large heads (a secondary sexual trait) in male insular anoles. In Chapter 3, I show how a many-to-one pattern between architectural design and material properties likely resulted in a macroevolutionary trade-off between the cross-sectional shape of the Anolis femur and its mineral density. This trade-off, which is observed in both sexes, seems to have enabled island and mainland species to evolve divergent phenotypic combinations while nonetheless achieving similar performance levels. Together, these chapters shed new light on the evolution of sexual dimorphism, documenting clear evolutionary differences in settings thought to differ in the intensity of sexual selection, and demonstrating the importance of incorporating performance into the study of sexual dimorphism.
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".