Meeting Abstract
Phenotypic plasticity allows organisms to respond quickly to changing environmental conditions, and may influence patterns of future evolution by exposing new variants to selection. However, relatively little is known about the genetic basis of plasticity – e.g., What are the genetic factors that influence the ability to mount a plastic response? Are coordinated plastic responses across anatomical units mediated by many distinct loci or by a few “global” regulators? To address these outstanding questions, we reared a hybrid cichlid mapping population on alternate benthic/pelagic diet regimes, which mimicked natural variation in foraging preference across cichlid species. We documented plasticity for an array of ecologically relevant traits including craniofacial, whole body, pectoral fin, and pharyngeal jaw shapes. We found a notable degree of correlation among traits, which confirms a coordinated plastic response. We next sought to assess the degree of overlap in the genetic control of plasticity. To this end, we scanned the genome for plasticity loci across these distinct traits, and again observed a similar pattern of correlation in the genetic determination of plasticity. In all, our data provide support for the existence of global regulators of plasticity, serve as an important step toward further characterizing the genetic basis of plasticity in cichlids, and provide a list of candidate loci for future functional analyses, including an activin receptor gene that may be key for plasticity in craniofacial, fin, and body musculature.
