
Extract the answer to the question from the following context.
Question: What has selective breeding done to French Bulldogs that makes it impossible to mate?
Context: Some dog breeds have acquired traits through selective breeding that interfere with reproduction. Male French Bulldogs, for instance, are incapable of mounting the female. For many dogs of this breed, the female must be artificially inseminated in order to reproduce.

Male French Bulldogs, for instance, are incapable of mounting the female
