An Astonishing Hybrid Nut:

The nuts appeared practically indistinguishable from ordinary filberts or hazelnuts, and the hybrid hypothesis seemed untenable because the alleged parental trees belonged to very different and unrelated plant families. Filberts belong to the birch family (Betulaceae), while figs belong to the mulberry family (Moraceae). In addition, filberts are typically wind-pollinated, while figs are pollinated by minute, species-specific wasps that enter specialized flower-bearing structures called syconia. The light spot on the outer pericarp seemed a little darker than most filberts, but no other visible distinctions could be detected by Professor Armstrong's careful analysis. The next obvious step in the investigation was to examine the seed enclosed within the hard-shelled nut. Using the sturdy metal base of a ring stand, Professor Armstrong carefully applied a forceful blow to the pericarp wall, fracturing it into several pieces. At that instant a light-colored object flew up into the air, momentarily defying the laws of gravity. Professor Armstrong caught the airborne object with his left hand, and to his astonishment (and to the utter amazement of the class), it was a condom.