One:Echindae

For uncountable years, the echidnae and platypuses retained a tenuous yet bizarre hold on terrestrial/aquatic life. Both monotremes ultimately went extinct in _____ when it became widely believed that the liquid that simultaneously binds together and lubricates the leathery shell of their eggs could successfully treat emotionally transmitted diseases. This theory was initially put forth by impossibly cheery spokesmodel-cum-newscaster Judy Unisex on her “New New Views of New New York Today” show, which was consistently ranked as the first or second most popular broadcast (of any medium or wavelength) for many decades following the post-plasma breakdown. The primary competition for the show being, of course, "Tacos for Keyholes" at least until the mysterious, untimely disappearance of the latter’s host. On her deathbed, however, Judy made, and then retracted, and then reiterated a shocking admission: that she had accepted cash and love from a particularly fluffy AFL-CIO-CAAT operative, in exchange for providing repeated on-air testimonials and reminders of the importance of monotremic glandular fluids to maintaining her own irrepressible perkiness. This statement confirmed officials’ worst fears: that the giller/CAAT unity would stop at nothing in their goal of radical species redefinition (“Placentas for Parity!” being one of the group’s rallying cries).