Everybody is now using the science terms related to COVID-19. People talk about the SARS-CoV-2 virus, messenger RNA, immunity, vaccines, spike proteins, mutations and the increasing numbers of COVID-19 variants. So, what’s a variant? It’s a different form of the virus with mutations resulting in a different RNA genetic sequence, which in turn results in different properties (infectivity and lethality). Variants that might pose a public health threat are called “variants of concern” by the Centers for Disease Control and Prevention.
You know from DNA profiles that different bulls have different DNA sequence mutations that result in different performance traits of their daughters. So, maybe each bull could be called a variant. Of course, you would just designate a bull by his name/number and not call him a variant. I suppose you could also call a breed a variant, but the word “breed” works just fine.
The point is that words have meaning, and they should be used appropriately for effective communication and policy. Consider wildlife, which also have variants. You know them as the variants called species and populations—like the population of the elk species in the Sangre de Cristo Mountains in Colorado Game Management Unit 82. The Endangered Species Act (ESA) designates populations called distinct population segments (DPSs).
The ESA also recognizes subspecies, which are populations that are in some way distinct from other populations of the same species. Subspecies are like livestock breeds, but they are not clearly distinct because wild animals move and interbreed over time. It follows that DPSs are also not clearly distinct. So, COVID-19 variants, DPSs and subspecies are categories that are not definite but are designated with informed judgment.
I described the complications of wolf subspecies and DPSs previously (WLJ, Feb. 18, 2019), and Anna Miller’s excellent articles in the Feb. 21 and March 7 editions of WLJ describe the recent ESA relisting of the wolf DPS in the lower 48 states and the petition to relist wolves in the Northern Rocky Mountain (NRM) DPS. It’s confusing that the ESA lists subspecies and populations, but that’s wildlife law these days.
Now consider this. The wolves in the NRM DPS originated from natural immigrants and introduced wolves of the northern subspecies in Canada; the Mexican wolf in southern Arizona and New Mexico is considered a subspecies and is listed as an endangered species; and there are plans for wolves to be introduced into Colorado.
The National Academies of Sciences, Engineering and Medicine concluded the Mexican wolf is a valid subspecies—although I think this is uncertain because scientists acknowledge that subspecies designations are subjective (see references.)
In any event, whatever the source of wolves that will be put into Colorado, they will not be the Mexican wolf subspecies. So, what happens if and when wolves in Colorado disperse southward and meet up with the Mexican wolves? They will likely both interbreed and kill each other (wolves killing each other is common in wild wolves). I guess they’re like people in some ways.
Regardless, a mixed population will result, selection will determine what genes and characteristics persist over time and the population will not be the same genetically as the existing ESA-listed pure Mexican wolf subspecies. It will be a new “variant” population. How this is handled with regard to the ESA remains to be seen, but NRM wolves mixing with the Mexican subspecies is a threat to its genetic distinctiveness.
Maybe wolves from the North and South won’t ever meet, but wolves disperse long distances. For example, NRM wolves expanded from Idaho, Montana and Wyoming into Washington, Oregon and California, so it is possible, and even likely, that wolves from Colorado will eventually contact the Mexican wolves in Arizona and New Mexico.
This issue should be addressed by the state of Colorado and in a federal environmental impact statement regarding introduction of wolves to Colorado and their subsequent spread. What, if anything, is going to be done to protect the Mexican wolf subspecies from mixing with NRM wolves? Will crossbreeding of northern and Mexican wolves result in more genetic diversity and increase fitness?
These are academic questions regarding the classification of wolf populations. The practical issue is managing wolves in different geographic areas regardless of subspecies designation. The most important management questions involve minimizing wolves’ impact on the livestock and game populations upon which Americans’ livelihoods depend. This is currently being debated in Colorado, and preliminary assessments are available at www.northwestbiology.com/publicationsreports. — Dr. Matt Cronin
(Matthew Cronin was a Research Professor at the University of Alaska and is now a scientist with Northwest Biology Company LLC in Bozeman, MT. He can be reached at croninm@aol.com.)
Cronin, M.A. 2020a. Wolves in Colorado: Insights from Wyoming, Idaho, and Montana. Unpublished report, Northwest Biology Company LLC, Bozeman, Montana, June 2020. www.northwestbiology.compublicationsreports
Cronin, M.A. 2020b. Hypotheses: Wolves in Colorado. Unpublished report, Northwest Biology Company LLC, Bozeman, Montana, July 2020. www.northwestbiology.compublicationsreports
Cronin, M.A. 2020c. Hypotheses: Wolf Predation on Elk in Colorado. Unpublished Report, Northwest Biology Company LLC, Bozeman, Montana, August 2020. www.northwestbiology.compublicationsreports
Cronin, M.A. 2019, 2021. Wildlife, War, and God Liberty Hill Publishing, Maitland, Florida.
Cronin, M.A. et al. 2015a. Single nucleotide polymorphism (SNP) variation of wolves (Canis lupus) in Southeast Alaska and comparison with wolves, dogs, and coyotes in North America. The Journal of Heredity 106:26-36.
Cronin, M.A. et al. 2015b. Wolf Subspecies: Reply to Weckworth et al. and Fredrickson et al. The Journal of Heredity. 106:417-419.
Cronin, M.A. and L.D. Mech. 2009. Problems with the claim of ecotype and taxon status of the wolf in the Great Lakes region. Molecular Ecology 18:4991-4993.
Cronin, M. A. 2006. A Proposal to eliminate redundant terminology for intra-species groups. Wildlife Society Bulletin 34:237-241.
National Academies of Sciences, Engineering, and Medicine 2019. Evaluating the Taxonomic Status of the Mexican Gray Wolf and the Red Wolf. Washington, DC: The National Academies Press. https://doi.org/10.17226/25351.
SARS-CoV-2 Variant Classifications and Definitions. SARS-CoV-2 Variant Classifications and Definitions (cdc.gov)
