It might shut some down?
When they are done well (calibrations accurate), and to within their (often huge for molecular clocks) margins of error at least.
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The dates they obtained for the split between lemurs and haplorrhines, and between tarsiers and simiiforms, are grossly too old. They used modern mutation rates for their calibration and distinguished between beginning to diverge genetically versus full species separation. They also used machine learning techniques to try to identify and compensate for biases in the program’s estimation of relevant evolutionary patterns. While noting the existence of biases in the analysis program is of value, it is somewhat problematic to use similar analyses to check for the bias. As usual, there is no quantitative substantiation of claims that the molecular dates match; instead they give these sample numbers and claim that the match is good. Here’s their table; I can’t say this convinces me that the match with the fossil record is great, especially as they give no reason why they picked these examples rather than giving a full comparison of all fossil dates.
Name of clade Node in fig.1B CoalHMM estimate (MYA) Literature estimate (MYA) Reference
Theropithecus A 2.3±0.05 4±0.4 (88, 89)
Homo-Pan B 5.9±0.13 6.5±0.8 (90, 91)
Papionini C 3.8±0.09 7±1 (92)
Cercopithecidae D 7.9±0.92 9±1 (93)
Hominidae E 16.2±0.36 15.5±2.5 (91, 94)
Platyrrhini F 26.5±0.74 23.5±3 (91, 95, 96)
Catarrhini G 29.4±0.33 29±6 (91, 97)
Simiiformes H 35.2±2.7 43±4.5 (97, 98)
Strepsirrhini I 61±1.8 52.1±2.7 (99)
Incomplete lineage sorting is most likely where there are large populations (most likely to have multiple alleles within the population) and short times between different species splitting off (less chance to lose the duplicates before a new split occurs). Reticulate evolution is especially common in plants, but happens some in all sorts of organisms.
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Yeah it’s really cool. The fossil record coupled with superimposed geological layers and chemical half lives there is also the “ genetic tree of life “ that can look at mutations since it’s the mutations that allow the divergent traits to continually alter the basal forms. You can look at a clade, and see all the similarities and differences. Then back trace it another clade and keep doing the same.
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