Perhaps we need to think about this.  And a lot harder than we seem to be thinking at present.

Do you know what the items in the following list are, and what they have in common: Macrostylis villosa, Galapagos Amaranth, Courtallum Wenlandia, Viola cryana, and Fitchia mangarevensis?

All of them are species of plants that once upon a time thrived in, respectively, Africa, the Americas, Asia, Europe, and Oceania.  Before the dawn of the twenty-first century, all of them had become extinct.

How about the items in this list:  Acipenser naccarii, Coregonus johannae, Cyprinodon arcuatus, Gila crassicauda, and Platytropius siamensis?

These are species of sturgeon, salmon, carp, smelt, and catfish that, likewise, have disappeared from the face of the earth.  It is beyond obvious to say that we shall never see them again.

Here’s an easier list:  Pachycephalosaurus, Dreadnoughtus schrani, velociraptors, Ankylosaurus, and therizinosaurs.  Do you know what these species have in common?

As you might have guessed, all are dinosaur species that became extinct more than 66 million years ago.

Try this one:  Dromaius minor, Camptorhynchus labradorius, Pinguinus impennis. Sceloglaux albifacies, and Ectopistes migratorius.

These are bird species that have ceased to exist—in order, the King Island emu, the Labrador duck, the Great auk, the Laughing owl, and the iconic passenger pigeon.

And now, perhaps the easiest list of all:  Balaenoptera musculus, Panthera tigris tigris, Elephas maximus sumatranus, Gorilla beringei graueri, and Diceros bicornis.

These are critically endangered animal species, on the cusp of extinction—the Blue Whale, the Bengal Tiger, the Sumatran Elephant, the Eastern Lowland Gorilla, and the Black Rhino.

Science estimates that approximately 99.9% of all the species of life that have inhabited this planet of ours since its formation are extinct.  In fact, Charles Darwin theorized that evolution and extinction are not mutually exclusive.

Or, as Annie Dillard put it, more poetically, in Pilgrim at Tinker Creek—

                         Evolution loves death more than it loves you or me.  This is easy to write,  easy to read, and hard to believe.

Still, if we can believe our planet has hosted some sort of life for more than 3.5 billion years, it’s staggering to think that less than one-tenth of one percent of all those lifeforms survive today.

Here’s a final list to ponder:  Homo habilis, Homo ergaster, Homo erectus, Homo heidelbergensis, Homo neanderthalensis, and Homo sapiens.

These, of course, are all species of human life, the first of which, scientists believe, first appeared around 2.5 million years ago.

Those of us alive today are members of Homo sapiens sapiens, a sub-species of the last one in the list, which is thought to have sprung up almost half-a-million years ago—not too long when compared to the 3,500 million years life has existed on earth.

But here is the critical implication arising from that final list:  of the six species listed, the first five have vanished.  We are the only ones not yet extinct.

Not.  Yet.  Extinct.

Perhaps we need to think more about that.