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Normal, but not this fast

Is Extinction Normal?

Almost every kind of animal that has ever lived is already extinct. What matters is not that it happens but how quickly.

Species that ever livedEvery kind, allof historySpecies alive nowAround one in ahundred
Extinction is the normal end of a species.
  1. Step 1 of 5

    Extinction means the last one has died.

    1 Many2 A few3 None — and noway back

    Not rare, not hiding — gone, with no way back. A species can be brought back from a handful of animals, but never from none.

  2. Step 2 of 5

    It has been happening steadily for as long as there has been life.

    The fossil record Almost entirelyspecies that are gone

    Species appear, last a few million years on average, and end. The fossil record is mostly a record of animals that are no longer here.

  3. Step 3 of 5

    Five times, that steady trickle became a flood.

    An ordinary million yearsA trickleA mass extinctionMost speciesgone

    A mass extinction wipes out most species in a geological blink. The famous one ended the dinosaurs; an earlier one was far worse.

  4. Step 4 of 5

    So the number that matters is the rate.

    The background rate A few species a year,worldwideThe rate now Many times higher

    Today species are disappearing far faster than the fossil background rate — fast enough that biologists argue about whether a sixth flood has begun.

  5. Step 5 of 5

    What makes it final is that a species is a recipe, not a thing.

    A body can bepreservedA picture can be keptThe instructionscannot be rebuiltThat is what makes itpermanent

    A species is millions of years of accumulated instructions. Burn the only copy and no amount of money or care writes it again.

    Extinction is not always a disaster for life as a whole — the end of the dinosaurs is exactly what left room for mammals.

The short version

Extinction is the ordinary end of every species, and nearly all have met it — so the alarming measurement today is the rate, not the fact.

Try it yourself

Name five animals that no longer exist. Every one you can name is from a very long list you cannot.

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