Have been told ponytail palms are male or female, and can tell the difference of each palm by the different shape flower.
How to Tell Difference Between Male and Female Flowers on Ponytails
My oldest ponytail, 45-50 years old, has been a member of the family 39 years. It bloomed once, about 7 years ago. Since the bloom spike was 15 feet in the air, and each bloom was so tiny, we didn't see any differences. No seed were produced. Sorry for not having a more definate answer to your question.