Dinosaur’s Demise

In response to “After Jupiter: How Likely Are We to Be Hit by a Rock?” Opinion, Aug. 21:

As fallout from the spectacular collisions on Jupiter, we were once again treated to an article stating that “one such (asteroid) probably ended the reign of dinosaurs.” I, like the vast majority of paleontologists who work on extinctions near the time of the dinosaur’s demise, know that these claims by physical scientists are simply wishful thinking. We don’t even have a worldwide record of dinosaur extinction. When and how fast the dinosaurs perished around the world remains a mystery.

Prof. Gregory Benford’s column does not stop with misinformation about dinosaur extinction. He adds a new bizarre twist by claiming that if we protect ourselves from objects from outer space with nuclear-tipped missiles, that “for once we humans would be defending the entire ecosphere, not just ourselves.” Since when did habitat destruction, outright hunting to extinction, pollution and the greatest single threat, overpopulation, stop being threats to the entire ecosphere? These very real impending disasters are far more worthy of our attention.

Finally, I certainly hope Prof. Benford had tongue firmly in cheek when he suggested that just as humans “are the sole stewards of our world, in all its rich abundance. The dinosaurs were once too--but look what happened to them.” Unlike the hapless dinosaurs, which had little control over their own fate, we know what we are calling down upon ourselves, and it isn’t unwelcome rocks from space.

J. DAVID ARCHIBALD

Professor of Biology

San Diego State University