Costal scales: referenced in Natator depressus page and mentioned(?) in other pages relating to snakes, etc. Research first and create here. Wanner method as well: Barry L. Wanner a method to disrupt chromosomal genes in E. coli in which PCR primers provide the homology to the targeted gene(s). In this procedure, recombination requires the phage λ Red recombinase, which is synthesized under the control of an inducible promote on an easily curable, low copy number plasmid.