Squash flowers with six petals?

I've never really paid attention to squash flowers, except to make sure they get pollinated.  One of my squash plants (the one we've always grown) is a banana squash and every single flower has six petals. I didn't think about it, except I was looking at another thread and every flower shown had only five.

So...

Apparently my yard enjoys popping surprises. Last year it was perfect watermelon flowers.

Is this normal? Do squash flowers often have six petals, or is it a fluke? I have no fruit yet this year--is this a possible reason?

I’ve got both from one seed packet, but the individual plants seem to have the same number as far as I can see.

So probably just an interesting mutation? I know the male flowers are fertile, because they were the only male flowers open to pollinate the other plants that popped out female flowers first. We've had one female flower on this plant, but it aborted.

Interestingly, with more watching, it seems both of these vines have a mix of both 5 and 6 petal flowers. These are “big max” pumpkin seeds I bought on a whim three years ago at the hardware store. I suspect it is just a natural variation within the species.

This year for the first time in over 40 years of growing squash I noticed one plant with 4 petals (Canada Crookneck moschata) and one with 9 petals (Pattison Golden Marbre pepo).  Weird.