Opening Pandora’s Molecular Box

Abstract

Mooi & Gill (2010) have prised open the cap of the molecular systematics vial and caused a debate to take-off in the ichthyological community. Molecular trees and their supporting evidence are the first two items to leave this Pandora’s box, closely followed by DNA barcoding and DNA taxonomy. In short, the debate is fuelled by the nature of molecular data: can nucleotide sequences provide the necessary evidence for relationship? The majority (Wiley et al., 2011) believe that DNA contains informative data; however, in our view, they have failed to ascertain the truth of their claim. Not all data are informative. Data may provide supporting evidence, conflicting evidence, or no evidence at all. Assuming that all data are informative apriori to analysis is a theoretical position, not an empirical one. We claim that systematics is, quite the contrary, empirical, and relies on evidence rather than on implicit measurements of data. Consequently, this assertion leads back to the original question of evidence in molecular systematics, namely molecular homology.

3ta Sleeps with the fishes

“…That, however, is not the only scheme for disposing of reversals by recasting homology. Ebach et al. (2011, p. 60) have another: 5…”

“…(2011a,b) and one by Craig (2011) are critical of Mooi and Gill (2010), while Mooi et al. (2011), Gill and Mooi (2011) and Mooi and Gill (2011) defend and clarify their ideas, with Ebach et al. (2011) and Nelson (2011) providing added support.…”

Overview

“…Papers defending the need for integration (Hastings 2011), and highlighting particular tools or approaches that facilitate the interpretation of molecular results (Faith et al 2011, Cruickshank 2011 are presented next. Further conceptual criticisms of the current molecular paradigm follow (Ebach et al 2011, Britz & Johnson 2011. Specific fish taxa are treated by Conway & Britz (2011; carps, Cypriniformes) and Dillman & Hilton (2011;sturgeons, Acipenseridae).…”