Elaine wrote:
OK lets say this is the only pumpkin or squash around in the area for
pollination purposes and the vine has male and female blooms which the bees
pollinate. Wouldn't it go back to whatever it's "parent" was?

Answer: maybe. The seedling will NOT produce seed that is true to type
unless the seed ITSELF was produced in the absence of another variety
of squash. So, the seed will produce fruit like the parent if no
othe squash was present at the time it was originally pollinated. If
there were no other varieties present then it would indeed "go back" to
it's original type.

I know that gourds are like that (other than they are pollinated by moths at
night). If you are growing one type of gourd you cannot grow another type
within several miles of each other due to cross-pollination and end up with
whatever weirdo.

Squash, pumpkins and gourds are all in the same family and can
pollinate each other. When this happens the fruit will be as expected
(true-to-type) but the seeds, if planted, will not produce true-to-type
squash. It will be a squash, for sure, but it will not be the named
variety that you started with. It will reflect the grab bag of genetic
material that the varieties involved were originally bred from and
every seedling could be as different from each other as they are from
the original variety.

If you are not growing for seed then there is no need to be worried
about such things. If seed production is the goal, however, care must
be taken to avoid accidental pollinations.