The extraordinary Atlantic silverside and me

Abstract My career is inextricably linked to the remarkable characteristics and astonishing insights provided by a simple yet elegant species, the Atlantic silverside, Menidia menidia. My initial field and laboratory studies provided the first demonstration of temperature-dependent sex determination (TSD) and its adaptive significance in fish, as well as the first empirical confirmation of frequency-dependent sex ratio selection. This early work then led to the discovery of countergradient variation in growth, evolutionary trade-offs associated with growth, pioneered the study of fisheries-induced evolution, and furthered our understanding of the spatial scale of local adaptation in marine species. Most of these topics are now vigorous areas of research encompassing numerous species and systems. Here I describe how these unforeseen discoveries were made and led to other findings on bluefish (Pomatomus saltatrix) and striped bass (Morone saxatilis). An interest in leadership during my early years was later rekindled as I took on administrative roles. It all began with an intriguing observation stemming from my MS thesis that I was compelled to follow. My career illustrates the value of exploring deeply the natural history of lesser-known yet easy-to-study species and to follow unexpected observations even if peripheral to a preconceived plan of research.