It is not surprising that no one recognized our mystery seeds from last week, because they came from a plant that isn't known for its seeds: the pineapple, Ananas comosus.
I was more than a bit surprised when I cut into a pineapple from the grocery store and there were seeds!
With a little research, it turns out that according to this article at Purdue, pineapples can produce seeds. They are used in breeding of new varieties and generally result from hand pollination. The seeds are apparently hard to germinate, which is why the commercial plants are usually propagated vegetatively.
Probably you have seen instructions for starting new pineapple plants from the tops of pineapple fruit. Our family cut off the fruit part and suspended the top in water (as shown here).
Pineapples are a type of bromeliad that grows naturally in tropical conditions. They don't really enjoy our dry climate in Arizona.
Still, maybe someday it will flower and produce fruit.
If you are curious what the flowers look like and how pineapples are grown, the video from Dole pineapple shows more.
Have you ever found seeds in a pineapple? Have you ever grown one from a top?