PTP is Meaningless, T-PTP is Contradictory: A Reply to Trueman

CARPENTER, JAMES; GOLOBOFF, PABLO A.; FARRIS, JAMES S.

CLADISTICS (PRINT)

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 1998 vol. 14 p. 105 - 116

0748-3007

The T-PTP test for monophyly can attribute significance to entirely unsupported groups and even to both of two contradictory alternatives. The method of evaluating ?support? after replacing selected groups of terminals with reconstructed ancestors has similar drawbacks. The proposed placement of Onychophora among Arthropoda is unsupported by 12S data, and strongly refuted by other evidence. Attempts to justify T-PTP on Popperian grounds rest entirely on misunderstanding Popper's ideas. The PTP test assesses neither Popperian corroboration nor statistical confidence of phylogenetic conclusions. It can attribute high significance to data that support no resolved grouping. Efforts to salvage PTP by proposing new interpretations share the weakness that none of the proposed interpretations generally holds. None of these methods seems useful in phylogenetics.