Though not directly cited on their site, the Mammal Diversity Database (MDD) follows Hope et al. (2016, cited below), who tested three hypotheses using mitochondrial DNA from red squirrels (Tamiasciurus sp.) found along the west coast. Their first hypothesis (H1) was that there are three species of red squirrel: T. hudsonicus, T. mearnsi, and T. douglasii. This was the standard taxonomy at the time followed by most authorities. Ultimately, T. douglasii was the only well-supported species in their analysis. Hope et al. (2016) found the differences between T. douglasii and T. mearnsi to be untenable. The mitochondrial lineage found in the geographically-isolated T. mearnsi (which occurs in Baja California) extends throughout the range of T. douglasii in Vancouver Island. Their divergence is "minimal". However, Mearns's Squirrel is a conservation-dependent population currently considered Endangered by the IUCN Red List (de Grammont & Cuarón, 2018). As employed by Hope et al. (2016), this taxonomic merge reassigns T. mearnsi as the subspecies T. douglasii mearnsi to preserve its conservation status.
Hope AG, Malaney JL, Bell KC, Salazar-Miralles F, Chavez AS, Barber BR, and Cook JA. "Revision of widespread red squirrels (genus: Tamiasciurus) highlights the complexity of speciation within North American forests". Molecular Phylogenetics and Evolution 100 (2016) 170–182. https://doi.org/10.1016/j.ympev.2016.04.014 (Enlace)
Los desacuerdos no deseados ocurren cuando un padre (B) es
disminuido al mover un hijo (E) a otra parte del árbol taxonómico,
resultando en que los IDs existentes del padre sean interpretados
como desacuerdos con los IDs existentes del hijo movido.
Identification
ID 2 del taxón E será un desacuerdo no deseado con la ID 1 del taxón B después del cambio de taxon
Si disminuir a un padre resulta en más de 10 desacuerdos no deseados, debes dividir al padre después de cambiar al hijo para reemplazar las identificaciones existentes de
el padre (B) con identificaciones que no están en desacuerdo.