[Updated Aug 6 2010: there was a key error in the steps between L3'4'6 and L4 and L3. In other words: I totally forgot about the L4'3 node and the three CR mutations defining it, pushing L(xL4'3) ahead in time some est. 9000 years. Corrected the main est. chronology now but left the text untouched otherwise]
Take what follows with the proverbial pinch of salt please. It's nothing but a working note.
The first West Eurasian lineages that show up in the downstream CR mutation count are R0 and M1, at 30 CR mutations counting from "Eve" (7 downstream of L3).
The first European-specific lineages are H and V at 33 CR mutations (10 from L3).
These facts may serve to generate a tentative chronology using the simplest molecular clock methodology: 1 CR mutation = 1 time unit.
A further control may be the place of K1 at 48 CRM (21 from L3), the most recent important clade showing signs of expansion in Europe/WEA, which should not be more recent than Neolithic.
The safest date for the colonization of Europe, which surely included an starlike expansion like the one we see at H, is that of Aurignacian expansion c. 40 Ka ago. A reasonable (but speculative) date for the arrival of H. sapiens to West Asia is c. 50 Ka ago.
This makes CRM=10/3=3.33 Ka.
To make calculations simpler I will round down this rate to CRM=3 Ka and take age(H,V)=40 Ka. as main reference.
Control: K1: 40-(3x11)=7 Ka ago. Fits perfectly: 7 Ka ago is roughly when Neolithic arrived to Central Europe, where K has been detected aboundantly in aDNA from the period and may be coincident with the expansion of K1.
- 148 Ka - Root ('Eve')
- 133 Ka - L1''6
- 121 Ka - L0, L1, L2"6 --- Beginning of Abbassia Pluvial
- 115 Ka - L0a'b'f'k
- 109 Ka - L5
- 100 Ka - L2'3'4'6, L0a'b'f
- 91 Ka - L0a'b, L0d, L1c --- End of Abbassia Pluvial
- 88 Ka - L0f
- 85 Ka - L3'4'6, L0d1'2
- 79 Ka - L2, L0a
- 76 Ka - L2a'd, L3'4
- 73 Ka - L4
- 70 Ka - L3 --- Out of Africa migration?
- 67 Ka - L4b, L3a, L3b'f, L3c'd'j, L3e'i'k'x
- 64 Ka - L3i, L3h
- 61 Ka - M, L1b, L3e ---- Beginning of Eurasian Expansion
- 58 Ka - L2b'c, L3f, M1'51, M3a, M3c, M4"64, M5, M9, M12'G, M13'46'61, M25, M29'Q, M32'56, M33, M34'57, M35, M40'62, M44, M49 ---- Arrival to East Asia and Melanesia
- 55 Ka - L1b1a, L2a, N, M30, M37, M7, M9a'b'c'd, M14, M17, M56, M36, M42, M52'58, M60, D --- Arrival to Australia
- 52 Ka - R, L0d3, L3d, M3b, M4a, M4b1, M4b2, M45, M13, M21, M27, M39, M71, N1'5, N9, S --- Final pan-Eurasian wave
- 49 Ka - R0, L4a, L3k, L3x, M2, M38, M43, M6, M8, G, M31, M54, O (N12), R2'JT, R6, R11'B7, B4'5, R30, R31, P ---- Colonization of West Asia
- 46 Ka - D4, L3e1, M1, M4c, M5a, E, Q, M32a'b, M53, N1, HV, R9, R12'21,
- 43 Ka - M63, M11, M29, M41, M73, D1, N2, N9a, N22, HV0a, JT, R5, R9b, U
- 40 Ka - H and V, L0k, L2a1, L3b, M1a, M64, M8a, Z, M12, Y, A, X, R0a, F, U6, U2'3'4'7'8'9 ---- Colonization of Europe, North Africa and NE Asia
- 37 Ka - M10, N5, N9b, X2, H1, H2, H3, H6a, H6b, H7, H9, H10, H13, H14, H15, H16, H17, R8, U6b, U4'9, U8
- 34 Ka - C, D4a1, A2, R0a2, H2a, H8, H11, H12, H18, H19, J, U3, U5, U6a --- Beginning of coldest conditions
- 31 Ka - L6, L3c, L3j, H4, J1, U5a, U6d ---- Gravettian
- 28 Ka - L2d, M7a1a, M23, R2, J1c, J2, R7, R11, U1, U5b
- 25 Ka - L2e, N1a, I, U6c, U2b, U5b3, U9
- 22 Ka - W, J2b, U4 --- Solutrean
- 19 Ka - K, D4h3a
- 16 Ka - M51, T, K2 --- Magdalenian, end of coldest period
- 13 Ka - T1
- 10 Ka - T2, K2a --- End of Ice Age, earliest Neolithic, Epipaleolithic
- 7 Ka - K1 --- European Neolithic
- 4 Ka - K1a1, T2b
Note: bold type is arbitrary for perceived "most important haplogroups", however font size reflects the presence of star-like nodes: large size for 5-12 branches, largest size for >15 branches. Clades are listed in logical phylogenetic order with a few exceptions when a single node seems to define a whole phase, in which case they have been listed first. All suggested dates are in thousand years (Ka) ago.
Of course there's no way I know of properly estimating the effective mutation rate at each space-time, which should be affected by issues as population size and, with low population levels specially, purely random accidents (drift). Still, I would prefer a logarithmic approach, with longer times/mutation towards the past and smaller ones towards the present.
That would probably be better because it would allow to push the L2 and L3'4'6 expansion towards a more realistic date at the beginning of the Abbassia Pluvial, when we see clear signs of expansion in North Africa and Palestine and also would push the root of the tree (the earliest genetic signal of expansion of H. sapiens) closer to the oldest known fossils c. 160 Ka.
Another issue is the known length of downstream branches, even in some well studied lineages, which appear almost "frozen" since their expansion. This seems to happen in particular to large star-like lineages like M and H (not sure why) but, in any case, the high variability in the length of the lineages towards the present is an anomaly that I would rather not have to face.
In this regard, notice the star-like expansions within the K and T haplogroups by the end of the (always tentative) chronology, wouldn't they be better some 3,000 years earlier? That way T2 and K2a could take part in the Magdalenian expansion, while K1a1 and T2b would belong to the Neolithic expansion. But maybe they fit well with Epipaleolithic and what I imagine as some phase of the Indoeuropean expansion... somehow.
A corrected 2.7 Ka/CRM ratio would fix that.
But it would also push the oldest dates forward quite a bit (for instance the root would be at just 129 Ka), so I feel I need a more refined approach: which should probably be a logarithmic or quasi-logarithmic equation that could account for estimated population sizes. However my maths skills are terribly rusty...
See also PhyloTree for a whole comprehensive mtDNA phylogeny.