Here is the headline for this story:

Biologists say half of all species could be extinct by end of century

Then the rest of the story goes on to offer not a single bit of evidence for this pessimism. Worse, one of their sources is Paul Ehrlich, who for some reason is still associated with Stanford. Professor Ehrlich has never been right about any of the myriad catastrophic predictions he has made. He's not the poster boy of reliable prediction the author is hoping for with this effort to alarm us.

I always ask: OK, name one mammal species that has gone extinct in the past 10 years? What was the extinction rate for all species 2000 years ago, and 200 years ago, and what is it now? I'm still waiting for alarming answers. Something like 98% of the species of animals and plants that have lived on earth are extinct. Extinction is as natural as, well, death. That certainly doesn't mean we have to help it along.

Fortunately for the author, the biologist who is making this claim of extraordinarily wide and rapid extinction is not Ehrlich but Professor Peter Raven, of the Missouri Botanical Garden. Oh, well that's completely different. The Missouri Botanical Garden is world famous for producing clear thinking biologists who don't make specious claims.

It seems to be worse for Ehrlich than normal. He is proposing somehow killing (or not replacing by unnatural birth control) about 6.4 Billion people.

A world population of around a billion would have an overall pro-life effect, Ehrlich argued.

I can't tell which method he really prefers. Just mandating birth control as the method for reducing the number of people on Earth will not reduce the population significantly in the 83 years we have left in the 21st Century. So the gathering scientists plan to avert the alleged 6th Great Extinction, caused by overpopulation, they say, without actually reducing the world's population significantly starting right freakin' now. How is that a good plan? Is the Vatican hosting a meeting where the plan is either genocide of humans on an unbelievable scale, or near universal birth control? Maybe the scientists are contemplating a third way and didn't tell the author of the piece.

Here is a list of 'species' that have probably gone extinct in the past 10 years (or so they believe--sometimes the species they call extinct are just hiding from them). It's possible I'm being picky here but all the mammals on the list are sub-species not species. There are still Black Rhinos (despite the stupid Chinese and unnecessary Arab choices which are killing too many each year). There are Clouded Leopards still throughout Asia and River Otters still throughout Asia and Europe. I think when you say here are species that have gone extinct, you really ought to mean species.

Also let's talk about island extinctions, as most of the list belong in that category. A lot of species which evolve on islands are easy pickings for predators introduced from continental sources. It is a very long list of island birds which were wiped out by pigs or rats or snakes that had not been there before and were introduced by people, often unknowingly. That's a tragedy but it's not the end of the world. It's not half the species gone in 83 years.

The Equadorians have done a very good job of preventing invasive species from ruining the Galapagos. Stopping invasive species would go a long way of preventing further island extinctions.

I've been hearing we're in a great modern extinction for about 20 years now. I'm willing to believe it but I have to know if the rate of extinction of species has gone way up lately and is accelerating in order to believe that a large percentage of species will be extinct before four score and three years have passed; and no one yet can tell me what the ordinary rate of extinction of species has been before human population topped Ehrlich's preferred one Billion around 1800. I don't believe the biologists and zoologists know what that rate was? Tough to talk about acceleration when you don't know the base rate.

Labels: Unskeptical Science; The 6th Great Extinction Prediction