Because.... Science!
Now Science says there was.
Maybe science is a process we have to try to figure things out rather then being a static item?
science doesn’t really “know” anything.
it can only say what it currently believes at this moment...
because all the stuff people make careers out of saying ‘this happened’ or ‘this is the law for this’ often turns out not to be, later on
and then theres the good old fashioned tricksters as well