Recognition of the importance of impact cratering ranks among the most significant advances in earth and planetary sciences of the twentieth century, but recently there has been a proliferation of reports of impact events and sites that eschew simple, less spectacular alternative explanations. Here we focus on (1) Holocene-age ocean impacts and associated “mega-tsunami,” and (2) a catastrophic impact event suggested at 12.9 ka. Carl Sagan once said that “extraordinary claims require extraordinary evidence”; we argue that these impacts do not meet that standard.
I am extremely dubious of an impact wiping out the NorAm megafauna, hoenstly, despite tha fact that a number of my coLabbies are convinced (and espouse) the theory. My biggest issue with it is that the megafauna of similar types and stripes, so to speak, didn't just die off in NorAm. It did all over the world. The same species from places other than NorAm went extinct too and at the same time...that's somethng that would argue for a cause other than an impact that limited its effects to NorAm.