Wing musculature reconstruction in extinct flightless auks (Pinguinus and Mancalla) reveals incomplete convergence with penguins (Spheniscidae) due to differing ancestral states

Despite longstanding interest in convergent evolution, factors that result in deviations from fully convergent phenotypes remain poorly understood. In birds, the evolution of flightless wing-propelled diving has emerged as a classic example of convergence, having arisen in disparate lineages including penguins (Sphenisciformes) and auks (Pan-Alcidae, Charadriiformes). Nevertheless, little is…