Research Fellows Directory
Dr Michael Morrissey
University of St Andrews
I study contemporary evolution in the wild. Work in recent decades has shown that most populations contain abundant genetic variation, and also that many traits appear to be subject to contemporary natural selection. Thus, the two key ingredients for adaptive evolutionary change are common in nature. However, stasis, or stability of traits, is by far the predominant pattern in traits through time. This indicates that we need more nuanced approaches to predicting when adaptive evolution will happen.
Several explanations exist for why stasis might commonly occur despite widespread apparent natural selection of genetically variable traits, however most are not well studied. For example, it has been suggested that selection fluctuates, and so cancels out in the long term; this explanation is not well-supported by available data (1). Another explanation is that not all trait-fitness relationships should be interpreted as natural selection, and so should not be interpreted as natural selection; this explanation is supported, e.g. (2), but has not been tested in enough systems to draw general conclusions. The work for my Royal Society University Research Fellowship seeks to develop a system for testing how the potentially complex relationships among traits that arise through development might influence adaptive evolution.
(1) Morrissey and Hadfield. 2012. Directional selection in temporally replicated studies is remarkably constant. Evolution 66: 1037-1047.
(2) Morrissey et al. 2012. The prediction of adaptive evolution: empirical application of the secondary theorem of selection and comparison to the breeder’s equation. Evolution 66: 2399-2410.
Interests and expertise (Subject groups)