Thank you for that cut-n-paste from Attention Required! | Cloudflare
or wherever else copies also exist. Were I to give as much time and thought composing my reply as you did I'd have to close now.
You asked why there were no *living*
hominid species more closely related to us than chimps and bonobos. That you said "living" implied that you understood that those more closely related are extinct. But now I can see that you don't accept that these extinct hominid species are related to us, so now you appear to be asking a different question. You appear to be asking why is the gap between chimps/bonobos and humans so large?
But if you do not accept that the extinct hominid species are related to us, why do you accept that chimps and bonobos are related to us when they resemble us even less?
There can be no specific evidence-based scientific answers for why most species went extinct, because the evidence just doesn't exist. We understand the causes of extinction and can engage in informed speculation, but that is as far as we can go. I don't even know why my Great Uncle Meier's line went extinct (other than the obvious "he failed to reproduce"), I can't imagine how we would ever determine why a couple million years ago the last australopithecine failed to produce descendants.
At one point you asked for scientific evidence that 99% of all species that ever existed are extinct. The Wikipedia article on Extinction Events
provides a slightly different figure:
Over 98% of documented species are now extinct...
And it provides this reference:
Wikipedia reference writes:
Fichter, George S. (1995). Endangered Animals. USA: Golden Books Publishing Company. pp. 5. ISBN 1-58238-138-0.
And the Wikipedia article on Extinction
provides yet another figure:
Most extinctions have occurred naturally, prior to Homo sapiens
walking on Earth: it is estimated that 99.9% of all species that have ever existed are now extinct.
And it provides these references:
Wikipedia references writes:
Newman, Mark. "A Mathematical Model for Mass Extinction". Cornell University. May 20, 1994. Retrieved July 30, 2006.
Raup, David M. Extinction: Bad Genes or Bad Luck? W.W. Norton and Company. New York. 1991. pp. 3—6, ISBN 978-0-393-30927-0
I happen to own that last reference, and here's a brief excerpt:
David M. Raup in Extinctions: Bad Genes or Bad Luck? writes:
There are millions of different species of animals and plants on earth - possibly as many as forty million. But somewhere between five and fifty billion
species have existed at one time or another. Thus, only about one in a thousand species is still alive - a truly lousy survival record: 99.9 percent failure.
The technical paper by Mark Newman can be found here: A Mathematical Model for Mass Extinction
. An excerpt:
Mark Newman writes:
Of all the species that have lived on the Earth since life first appeared here 3 billion years ago, only about one in a thousand is still living today.
Newman has also written the book Models of Extinction: A Review
with R. G. Palmer, and chapter 2 is a detailed review of the data that went into formulation of extinction models and that provides support for the 99.9% figure.
Edited by Percy, : Grammar.