We examined birth sex ratios in relation to mare body condition at conception in horses in which male reproductive success is differentially helped by slight advantages in condition. Excessive promotion of a stallion by its owner or related parties is not permitted and will be addressed at the discretion of the moderators. Abstract We investigated mutual grooming by Jeju pony Equus caballus foals to determine whether male foals preferentially interact with potential future sexual partners or competitors. Utilize the private message feature or personal email where appropriate to address side topics or personal issues not related to the topic at large. Keep conversations productive, on topic and civil.