Category Archives: Species Discovery

Review of the Sixth Extinction, Part 2

And I’m back with a second part to my thoughts on the Sixth Extinction, because the book has just stuck in my craw. I’m still mulling it over.

Extinctions seem to be quiet. Most go unnoticed. The end might be violent (see:  great auk) or unassuming in the wild (see:  baiji freshwater dolphin) but it is the most grievous sort of death. Humans take some comfort that they have passed something on to future generations of their ilk when they die; no such succor can be had for extinct species.

According to Dr. Anthony Barnosky, about 900 species’ extinction can be directly attributed to human cases over the last century, and around 20,000 species now are known to be at risk. The even more terrible news is that humans have killed off half of all wildlife in the last 40 years. (HHMI, 2015)


Biodiversity in the Age of Humans, HHMI 2015.

We don’t even seem to be aware of the magnitude our actions can have–seven billion is a jumbo number to try to visualize and connect down to my own measly life.

And yet, even at much lower numbers, we have been having an outsize impact for thousands of years.

As Kolbert incisively noted:  “When Alroy [a paleobiologist] ran the [extinction] simulations for North America, he found that even a very small initial population of humans—a hundred or so individuals—could, of the course of a millennium or two, multiply sufficiently to account for pretty much all of the extinctions in the [fossil] record…if every band of ten hunters killed off just one diprotodon a year, within about seven hundred years, every diprotodon [large marsupial] within several hundred miles would have been gone…From an earth history perspective, several hundred years or even several thousand is practically no time at all…For the people involved in it, the decline of the megafauna would have been so slow as to be imperceptible…Alroy described it as ‘geologically instantaneous ecological catastrophe too gradual to be perceived by the people who unleashed it.’ ” (233-234)

We can perceive what we are currently unleashing, so at least we aren’t in the dark anymore. While there are a lot of players involved in the extinction game, spread all over the world, there are definitely things that can be done in our backyards.

And, for me, that’s the challenge–to not let this be such a hulking, intimidating beast of a task that I don’t even try beyond the shallowest of actions. Those actions matter, but they are not nearly enough. I will be working through different steps I can take locally to shore up all wildlife–because even species that are common are likely struggling.

In Plain Sight

I braved the bitterly bracing cold, so gusty that I had to walk backwards for about a block in order to breathe, to hear about these frogs that had been hiding in plain sight. I forced a lot of my nerdy frog facts onto others in the days after the lecture, so here are some highlights for posterity:

  • Frogs don’t have regional accents in their croaking, unlike birds.
  • Individual appearances can vary more within the same species than between species of frogs, when selecting random specimens. This is called a cryptic species.
  • Extirpation is a possibility for this frog on Staten Island, where it was discovered.
  • The man, Carl Kauffeld, who originally discovered this species couldn’t even correctly identify all of his specimens correctly as part of this species. That’s how confounding identification was before genetics and bioacoustics.
  • Herpetologist is a fun, funny word.

Here’s hoping in this densely packed urban corridor that this frog, which needs ample space and specific marshy habitats, can make a successful stand. This story has reminded me that the coolest nature can be found in and around cities. It’s our job to help out, so that these impressive survivors can do more than just eke out an existence.

Background Reading: