Interestingly, there is this paragraph in the Wikipedia article:

> Although Bateman's principle served as a cornerstone for the study of sexual selection for many decades, it has recently been subject to criticism. Attempts to reproduce Bateman's experiments in 2012 and 2013 were unable to support his conclusions. Some scientists have criticized Bateman's experimental and statistical methods, or pointed out conflicting evidence, while others have defended the veracity of the principle and cited evidence in support of it.

Seems like a very convincing conjecture otherwise, though.