Meeting Abstract
Competition is thought to play a major role in evolution, but it is difficult to observe its effects over macroevolutionary timescales. Here, we show that pharyngognathy, a classic example of evolutionary innovation, has affected niche evolution between major lineages of freshwater and marine spiny-finned fishes, including some of the most spectacular adaptive radiations on the planet. Experimental and historical evidence suggest that competition between pharyngognaths and an invasive non-pharyngognath played a major role in a recent mass extinction of fishes in Africa’s Lake Victoria. Nearby Lake Tanganyika also bears the signature of competition between pharyngognathous and non-pharyngognathous fishes over the last several million years. Finally, a large comparative analysis of dietary evolution in marine fishes reveals that over tens of million of years, fishes with the pharyngognathy innovation have gained improved access to novel prey categories, but at the cost of surrendering their prowess in predatory niches to close relatives lacking the innovation. Our results reveal that the ecological effects of competition can shape macroevolutionary dynamics, and that evolutionary innovation often carries a heavy ecological price.
