IS THERE ANY CONSENSUS ON BASAL ARCHOSAUR PHYLOGENY

Studies of basal archosaur phylogeny since 1975 were reviewed to asses s directly opposing views on the (dis)agreement reached as a result of adopting cladistic methodology. The transition to modern numerical cl adistic analyses has been long, including two principal stages: with l isting of derived characters as node support eventually replaced by ex plicit data and methodology presentation. All four existing explicit n umerical studies are reanalysed, and a semi-strict reduced cladistic c onsensus is constructed for them and compared with earlier 'cladistic' studies where data was not presented. The two principal steps to mode rn numerical analyses have been accompanied by an increase in the agre ement between separate hypotheses, and there exists substantial curren t consensus on the resolution of many pre-cladistically vague relation ships. However, Bremer support values calculated for the four numerica l studies indicate that the strength of hypothesised clades is general ly low to minimal. Because a previous review (Charig 1993) included ma ny non-cladistic studies, using its failure to find consensus as a bas is for broader criticisms of cladistic methods is considered unjustifi ed. However, some of Charig's (1993) criticisms of current practises a re endorsed. Reproducibility of results, greater methodological awaren ess, and more rigorous assessment of hypothesis robustness are identif ied as additional issues requiring consideration in future studies.