Salmon Life Histories
Research led by my postdoc Holly Kindsvater (now at Rutgers) confirmed that salmonid fish species that die after spawning produce much larger eggs than those that breed multiple times. We explained this with a theory concerning costs of reproduction, supported by a comparison among 363 populations of 13 species (Kindsvater et al. 2016). We also teamed up with Laura Weir to show that in salmon species that have male sneakers (small guys who sneak their sperm onto eggs instead of fighting), may lead to the evolution of smaller fighter males than in species that lack sneakers (Weir et al. 2016).
We have been examining patterns of change through time in life history traits and testing hypotheses that might explain them, using various fish and bird species. Have evolutionary transitions between male parental care and female care passed through an intermediate step of biparental care? How can we explain which sex provides care? Are differences between males and females in body size due to one sex having changed more than the other over time? Can temporal patterns of change be explained by changes in breeding systems? We have been using comparative studies of a variety of bird and fish species to answer these questions.
My comparative studies of birds have been done through a 20-year collaboration with my friend Tamas Szekely at the University of Bath. Look how happy he is!
The wordle below, from paper that I co-authored with Phil Molloy and others on impacts of fishing on sex-changing fish in 2007, says it all. Somehow, we managed to use the word “sex” 336 times!
Related articles – see Publications.
Molloy, P.P., Paddack, M.J., Reynolds, J.D., Gage, M.J.G. & Côté, I.M. (2010). Relative size-at-sex-change in parrotfishes across the Caribbean: is there variance in a supposed life-history invariant? Evolutionary Ecology DOI 10.1007/s10682-010-9404-3. pdf
Molloy, P.P., Goodwin, N.B., Côté, I.M., Gage, M.J.G. & Reynolds, J.D. (2007). Predicting the effects of exploitation on male-first sex-changing fish. Animal Conservation 10, 30-38. pdf
Thomas, G.H., Székely, T. & J.D. Reynolds (2007). Sexual conflict and the evolution of breeding systems in shorebirds. Advances in the Study of Behavior 37, 279-342.
Kolm, N., Goodwin, N.B., Balshine, S. & Reynolds, J.D. (2006) Life history evolution in cichlids 1: revisiting the evolution of life histories in relation to parental care. Journal of Evolutionary Biology 19, 66-75.
Kolm, N., Goodwin, N.B., Balshine, S. & Reynolds, J.D. (2006) Life history evolution in cichlids 2: directional evolution of the trade-off between egg number and egg size. Journal of Evolutionary Biology 19, 76-84.
Goodwin, N.B., Dulvy, N.K., & Reynolds, J.D. (2005) Macroecology of live-bearing in fishes: latitudinal and depth range comparisons with egg-laying relatives. Oikos 110, 209-218.
Székely, T., Freckleton, R.P. & Reynolds, J.D. (2004) Sexual selection explains Rensch’s rule of size dimorphism in shorebirds. Proceedings of the National Academy of Sciences 101, 12224-12227.
Goodwin, N.B., Dulvy, N.K. & Reynolds, J.D. (2002) Life-history correlates of the evolution of live bearing in fishes. Philosophical Transactions of the Royal Society of London 357, 259-267.
Reynolds, J.D., Goodwin, N.B. & Freckleton, R.P. (2002) Evolutionary transitions in parental care and live bearing in vertebrates. Philosophical Transactions of the Royal Society of London 357, 269-281.
Goodwin, N.B., Balshine, S. & Reynolds, J.D. (2001) Using phylogenies to test evolutionary hypotheses about cichlid fishes. Journal of Aquariculture & Aquatic Sciences 9, 256-268.
Liker, A., Reynolds, J.D. & Székely, T. (2001) The evolution of egg size in polyandrous shorebirds. Oikos 95, 3-14.
Székely, T., Reynolds, J.D. & Figuerola, J. (2000) Sexual size dimorphism in shorebirds, gulls and alcids: the influence of sexual and natural selection. Evolution 54, 1404-1413.
Goodwin, N.B., Balshine-Earn, S. & Reynolds, J.D. (1998) Evolutionary transitions in parental care in cichlid fish. Proceedings of the Royal Society of London B 265, 2265-2272.
Reynolds, J.D. & Székely, T. (1997) The evolution of parental care in shorebirds: life-histories, ecology and sexual selection. Behavioral Ecology 8, 126-134.
Székely, T. & Reynolds, J.D. (1995) Evolutionary transitions in parental care in shorebirds. Proceedings of the Royal Society of London B 262, 57-62.