Data and script for: Weapons evolve faster than sperm in bovids and cervids

In polyandrous species, males face reproductive competition both before
and after mating. Sexual selection thus shapes the evolution of both pre-
and postcopulatory traits, creating competing demands on resource
allocation to different reproductive episodes. Traits subject to strong
selection exhibit accelerated rates of phenotypic divergence, and
examining evolutionary rates may inform us about the relative importance
and potential fitness consequences of investing in traits under either
pre- or postcopulatory sexual selection. Here, we used a comparative
approach to assess evolutionary rates of key competitive traits in two
artiodactyl families, bovids (family Bovidae) and cervids (family
Cervidae), where male-male competition can occur before and after mating.
We quantified and compared evolutionary rates of male weaponry, body
size/mass, testes mass, and sperm morphometrics. We found that weapons
evolve faster than sperm dimensions. In contrast, testes and body mass
evolve at similar rates. These results suggest strong, but differential,
selection on both pre- and postcopulatory traits in bovids and cervids.
Furthermore, we documented distinct evolutionary rates among different
sperm components, with sperm head and midpiece evolving faster than the
flagellum. Finally, we demonstrate that, despite considerable differences
in weapon development between bovids and cervids, the overall evolutionary
patterns between these families were broadly consistent.