Organismal development is a complex process, involving a vast number of molecular constituents interacting on multiple spatio-temporal scales in the formation of intricate body structures. Despite this complexity, development is remarkably reproducible and displays tolerance to both genetic and environmental perturbations. This robustness implies the existence of hidden simplicities in developmental programs. Here, using the Drosophila wing as a model system, we develop a new quantitative strategy that enables a robust description of biologically salient phenotypic variation. Analyzing natural phenotypic variation across a highly outbred population, and variation generated by weak perturbations in genetic and environmental conditions, we observe a highly constrained set of wing phenotypes. Remarkably, the phenotypic variants can be described by a single integrated mode that corresponds to a non-intuitive combination of structural variations across the wing. This work demonstrates the presence of constraints that funnel environmental inputs and genetic variation into phenotypes stretched along a single axis in morphological space. Our results provide quantitative insights into the nature of robustness in complex forms while yet accommodating the potential for evolutionary variations. Methodologically, we introduce a general strategy for finding such invariances in other developmental contexts.
Data will be made publicly available at Mani, Madhav, 2021, "Imaging data from "Global Constraints within the Developmental Program of the Drosophila Wing"", https://doi.org/10.7910/DVN/UFGJFB, Harvard Dataverse, V1
- James Carthew
- Richard W Carthew
- Madhav Mani
- Vasyl Alba
- Richard W Carthew
- Madhav Mani
- Madhav Mani
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Danelle Devenport, Princeton University, United States
© 2021, Alba et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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