Barcoding and the practice of systematics

Richard Lane

What are systematics and barcoding trying to do?

Systematics • Discover and delimit taxa • Classify taxa based on testable relationships (phylogenetic) • Provide guides to identification DNA barcoding • Diagnostic • Discover ‘new’ taxa • Sequence data for systematic research

Relative importance of components

Systematics • Discover and delimit taxa •

Classify taxa based on testable relationships (phylogenetic)

• Provide guides to identification DNA barcoding •

Diagnostic

• • Discover taxa Sequence data for systematic research

Concerns over DNA barcoding

Barcoding : • Will not distinguish all species (will not work) • Diverts funds or attention • Philosophically unsound (=pheneticism)

Will not distinguish all species

Testable with empirical data: • Plants not distinguishable by single CO1 seq • Where many taxa sampled, >> 95% discriminated • ‘new’ taxa indicated • Species complexes not always discriminated

Diverts funds or attention [from more important elements of systematics]

Funding: assumption of finite resources, competition analysable – qualitative methodology Relative importance: value-based

Philosophically unsound (=pheneticism)

Only relevant if barcodes used for

classification,

not if used for

identification

Questions?