[anotherpaul]

I agree that the species concept is a bit of a mess but how do you conclude that these two populations can still interbreed?

From the article I do not get the same suspicion. Even though they mention the "sister species" is 1200km removed this might be true while being a "finished" allopatric speciation.

From the paper:

"Our fossil calibrated mitochondrial clock analysis estimates the most recent common ancestor of C. congoensis and C. satanas existed ~4.27–5.78 Ma. In an additional analysis that used the same secondary calibration point as Roos and Zinner [36], we obtained younger divergence estimates by approximately 1 million years (3.44–4.73 Ma)."

[Myrmornis]

Hi, two answers:

Firstly,

> how do you conclude that these two populations can still interbreed?

I'm saying that people shouldn't spend time asking that question of allopatric populations.

Secondly you're right that I didn't read up on these monkeys. I wanted to rant about species concepts, but I was doing it in a discussion about some doubtless wonderful and very interesting monkeys and I am definitely guilty of not doing justice to them or to the people studying them.