Yep, I'm glad to know I am part of a "weed" species. They did cover the extinction/production cycle, however it is evil if people cause the extinction. They did note that 95% of all species are fossils only. I'm pondering the average 4,000,000 year species life-time(I think I heard that number). We need to exterminate the coelecanth, it's skewing the curve.
A sad deviation from what otherwise so far has been a very informative program. From the way they talked during the second half of episode #2, you'd think it's only bad if Hawaii's birds go extinct from "immigrant" brown tree snakes that come in via boats an planes; if a bunch were ever to get there on a pile of tress blown there from some other Pacific Island on which the snakes are indigenous by a typhoon (and likely they would eventually, given enough time and enough typhoons and enough snakes), then the extinction of the birds would be natural and hence okay. Way too PC for my taste.
...and the shark, and the blowfish, and I believe that roaches too have been shown to be hundreds of millions of years old too, of course there is also my favorite species the platypus which has been proven not to have changed in some 100 million years.