Hi all
* I don't know how deeply folks want to go into this, but here are a few more thoughts on the topic:
A further problem with the subspecies concept, from a practical point of view, is its application in legislative policy and biodiversity conservation. Subspecies are frequently the focus of protective legislation and conservation programmes, but inconsistencies in subspecies taxonomy as a result of disagreements in species concepts and a lack of standardized criteria for their diagnosis, together with biases in taxonomic coverage of groups/regions, have made it difficult for government agencies and nongovernment organizations to evaluate their validity in the listing process for conservation.
Given that taxonomy is a major scientific discipline that underpins the preservation of biological diversity, there is an urgent need for an evidence-based rigorous definition of subspecies to allow prioritization of resources for the protection and effective conservation management of that diversity.
Wilson & Brown (1953) and Gillham (1956) recommended that the subspecies concept be abandoned because subspecies are often poorly diagnosed, their delimitation is difficult to determine (especially for parapatric populations), and taxonomic decisions made for a particular set of populations are often arbitrary, subjective, and based on too few characters.
In short, it was concluded that '‘the subspecies was not a concept of evolutionary biology but simply a handle of convenience for the clerical work of the museum curator ... the primary use of subspecies is as a sorting device in collections."
The selection of characters on which to delineate subspecies requires careful consideration because it is apparent that some morphological characters are too labile and unreliable (Burbrink et al., 2000), whereas others are environmentally plastic and lack evidence of heritability. -- Braby, M. F., Eastwood, R., & Murray, N. (2012).
* Meanwhile, people are trying to make a case for preserving local ecotypes, even as they acknowledge that the genetic basis for these distinctions is highly ambiguous.
While A. m. iberiensis is still not endangered, conservation measures should be applied before unique combinations of traits shaped by natural selection are irremediably lost, a possibility if Spanish and Portuguese beekeepers adopt a strategy of importing commercial C-lineage strains. Cost-effective and robust reduced SNP assays were constructed from 176 WGS to detect C-lineage introgression into A. m. iberiensis. Moreover, this panel can be applied to the Canary Islands, the archipelago of Azores and Madeira where there are signals of hybridization between C-lineage and A. m. iberiensis.
SNP assays are a valuable tool to detect C-lineage introgression, a major concern in the fight to safeguard the reservoirs of unique combinations of genes and adaptations in A. m. mellifera and A. m. iberiensis. However, it should be noted, that these reduced assays are not suitable for standard population genetic analyses, including determining allelic diversity or measuring isolation by distance, genetic drift or bottleneck effect. The bias introduced through selection for markers that segregate among target populations would seriously compromise these calculations.
The maternal honey bee genetic variation has been widely accessed using the highly polymorphic tRNAleu -cox2 intergenic giving invaluable insights to characterize different populations. However, it is important to understand if this region is reliable for historical inference. The results showed that the popular tRNAleu-cox2 intergenic region does not represent the evolutionary history of the mitogenome. While the mitogenome analysis supports the three evolutionary lineages defined by the DraI restriction pattern of the tRNAleu-cox2 intergenic region, it does not support the existence of different African sub-lineages. In addition, different parts of the genome provided distinct results, implying that the conclusions drawn from studies using only one locus need to be taken with caution. -- Dora Sofia Martins Henriques (2018)
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