Do single mitochondrial gene barcodes reliably identify sister-species in diverse clades of birds?
Closely related sister species of birds can be identified reliably by barcodes of fixed diagnostic substitutions in COI sequences, verifying coalescent-based statistical tests of reciprocal monophyly for taxonomic distinctiveness. Contrary to recent criticisms, a single DNA barcode is a rapid way to discover monophyletic lineages within a metapopulation that might represent undiscovered cryptic species, as envisaged in the unified species concept. This identifies a smaller set of lineages that can also be tested independently for species status with multiple nuclear gene approaches and other phenotypic characters.
Vaginal sidewall and third-/fourth-degree perineal tears were found to be independent clinical indicators of an increased risk of levator trauma, as diagnosed by 4D translabial ultrasound 3-6 months postpartum. Such clinical markers may become useful in the identification of women at high risk of levator trauma and future pelvic floor disorders.