If the bible had instead described a 14.5b year creation period, including millions of years of biological evolution, would they still be digging up "evidence" to support the idea of a young earth?
I would say that whatever the Bible states, they'd go with.
The key point though, to support their argument, is that the Bible is quite vague in it's primitive attempt to describe our origin.
No time frame, no functinal biological processes, no mention of the laws of physics, etc. So this leaves it all to interpretation.
I don't know if there are any YEC's on this site with any real knowledge of science that would present you with a reasonable, scienctifc approach to their beliefs. I'd be curious to see what they have for "outside of the bible" evidence. My guess will be nothing.
Are there even YEC's on this site?
"I smoke pot. If this bothers anyone, I suggest you look around at the world in which we live and shut your mouth."--Bill Hicks
"I never knew there was another option other than to question everything"--Noam Chomsky