Based on what? Carbon dating is severely flawed. You can run the same artifact through the process and get results that vary by billions of years. It's a method that's practically useless. Those numbers are based on what someone with an agenda wants people to think. No one really knows for sure. Science has not been science for a very long time. The idea of testing a theory using a rational methodology to arrive at an accurate conclusion and accepting the resulting data used to be the way we got to specific conclusion. Now it's more like who's providing your funding, what is their political / financial motivation, and what results would they like you to produce. See dissenting scientists who have been blackballed for supporting conflicting ideas about MMGW, or ID for evidence. From what I could tell they had better and more accurate research, but were shut down because they went against the mainstream ideaology.
Now ACE using Nessie to support creationism is absurd, but it's equally absurd to espouse macro evolution as fact in a scientific environment. The evidence is pretty flimsy, and mired in overtly manipulated scientific results.