Because a universal flood is, as they say, universal. Or are you now agreeing with me that many small ice age floods are the cause of flood mythology? If it was deep enough to cover the mountains and only lasted 40 days, than it was deep enough, and turbulant enough, to distribute dead critters homogenously, not in lumps that associate with specific rock types. For one parameter of an equation to show stochastic distribution with local central tendencies is one thing. For another to match it, tells you there is correlation.
Than keep your denegrating, dismissive opinions of scientists and their life's work to yourself.
Actually the record says precipitation burst forth for 40 days and covered the mountains for a much longer period of time.