My mom researched this in college; A huge number of cultures and religions around the world including eskimos, sumerians etc etc have flood stories, some quite similar to the Bible. Add that to we know 10,000-15,000 years ago a huge 400 ft rise in the sea level at the end of the last ice age. Evolutionists like to tell us that the ice age ended slowly over hundreds of years and the sea level just gradually rose, however there is really no proof that the melting of the ice cap didn't occur quickly not slowly. And no proof the sea level didn't rise above the present level before it lowered down to the present sea level. Add that to the fact that maybe 95 % of the people live with in several hundred feet of the sea level. I for one believe there was a flood and that there was an ark, but that the occupants of the ark were definitely not the only survivors of the flood, some people were simply above the highest level of the flood, certainly Sherpas living at 15,000 feet on Mt Everest should have been above the flood.
Obviously the ark was not big enough to hold all the animal species of the time that survived the flood, but the flood could have wiped out all the inhabitants of Israel, Saudia Arabia, the middle East etc, as most of them are at lower elevations. Or maybe the ark landed way away from where its started, and the Middle East was not inhabited by humans prior to the flood. Obviously the flood did not occur only 4000 years ago, so that wipes out the whole 6000 year old world theory, even by reading the Bible, the 6000 year theory is full of holes, enough to sink an ark!!