who said we have no evidence for a young earth? for instance: (from my other thread) we have empirical evidence that speciation may take about less then 100 years:
Rapid Evolution Changes Species in Real Time | DiscoverMagazine.com
Watching new species evolve in real time
so lets assume a tipical speciation event= 100 years.
one of the largest family on earth is the curculionidae which contain almost 100,000 species. so if we start with 2 species then after about one generation of a speciation event (100 years) we will get 4 different species. and after another generation of speciation we will get 8 and so on. so we only need about less then 20 generation of speciation to get more then 100,000 different species (2^20) . or about 2000 years.
we also have evidence for a suppose 15-20 my old DNA. when science show us that a DNA cant survive so long time.