A pictorial version of the flying primate hypothesis.
The key features are:-
1. the colugo (gliding lemur) leaving a lower branch of the primate tree and representing a lineage ancestral to the flying fox (in mid air);
2. A separate earlier branch for microbats (top left) whose evolution of flight is unconnected with the evolution of flight in flying foxes (megabats)
In 1986 I had this drawing commissioned by Peter Schouten, renowned
for his pictorial reconstructions of past Australian fauna. At that
time I believed that tarsiers (little chap in the far right, vertical branch)
belonged to the anthropoids. ....Hence its position with the woolly monkey,
on a higher branch than the lemur (ruffed lemur, in black and white) and
loris (bush baby on vertical branch in middle).
Growing evidence, both molecular and morphological, indicates that the tarsier is not an anthropoid, but must have arisen from an ancient branch of the primates, close to the colugo with which it shares derived features not found in any other mammal.
If I were having the drawing commissioned today, I would put the tarsier on a branch that arose at the base, near the colugo.
Microcebus murinus, the mouse lemur, on Jack's thumb. This is the smallest extant primate.