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Abstract Divergence in body shape is one of the most widespread and repeated patterns of morphological variation in fishes and is associated with habitat specification and swimming mechanics. Such ecological diversification is the first stage of the explosive adaptive radiation of cichlid fishes in the East African Rift Lakes. We use two hybrid crosses of cichlids (Metriaclimasp.×Aulonocarasp. andLabidochromissp.×Labeotropheussp., >975 animals total) to determine the genetic basis of body shape diversification that is similar to benthic‐pelagic divergence across fishes. Using a series of both linear and geometric shape measurements, we identified 34 quantitative trait loci (QTL) that underlie various aspects of body shape variation. These QTL are spread throughout the genome, each explaining 3.2–8.6% of phenotypic variation, and are largely modular. Further, QTL are distinct both between these two crosses of Lake Malawi cichlids and compared to previously identified QTL for body shape in fishes such as sticklebacks. We find that body shape is controlled by many genes of small effect. In all, we find that convergent body shape phenotypes commonly observed across fish clades are most likely due to distinct genetic and molecular mechanisms.
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This content will become publicly available on June 25, 2026
Modularity of d$d$‐elliptic loci with level structure
Abstract We consider the generating series of special cycles on , with full level structure, valued in the cohomology of degree . The modularity theorem of Kudla–Millson for locally symmetric spaces implies that these series are modular. When , the images of these loci in are the ‐elliptic Noether–Lefschetz loci, which are conjectured to be modular. In the Appendix, it is shown that the resulting modular forms are nonzero for when and .
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- Award ID(s):
- 2302548
- PAR ID:
- 10618117
- Publisher / Repository:
- Oxford University Press (OUP)
- Date Published:
- Journal Name:
- Journal of the London Mathematical Society
- Volume:
- 112
- Issue:
- 1
- ISSN:
- 0024-6107
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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