Vouchered Specimens
DNA sequence databases like GenBank contain many sequences that are not tied to vouchered specimens (for example, herbarium specimens, cultured cell lines, or sometimes images). This is problematic in the face of taxonomic issues such as whether several species should be split or combined, or whether past identifications were sound. Therefore, best practice for DNA barcoding is to sequence vouchered specimens.
Read more about this topic: DNA Barcoding
Famous quotes containing the word specimens:
“A tattered copy of Johnson’s large Dictionary was a great delight to me, on account of the specimens of English versifications which I found in the Introduction. I learned them as if they were so many poems. I used to keep this old volume close to my pillow; and I amused myself when I awoke in the morning by reciting its jingling contrasts of iambic and trochaic and dactylic metre, and thinking what a charming occupation it must be to “make up” verses.”
—Lucy Larcom (1824–1893)