Darker Dall Sheep exist in both Dall and Stone subspecies with some intermediate mix of light and dark variations also being seen (sources below). It's clear the Planet Zoo Dall Sheep seems to be a mix of both subspecies (similarly to the Timber Wolf being a catch all for most Grey Wolf species as a whole (minus Arctics), not just actual Timber Wolves subspecies), so even the argument "oH tHey oNly exiSt in StoNey's" (spoiler alert, they might have used to, but this has changed through further studies) doesn't really work.
Here's what I'm talking about:
Sources:
https://en.wikipedia.org/wiki/Dall_sheep (Taxonomy and Genetics, paragraph 2-3)
https://yukonwildlife.ca/wildlife/thinhorn-sheep/11-20-thinhorn-mountain-sheep (first few paragraphs)
Actual genetic study by the University of Alberta:
www.ualberta.ca
CBC news article for the study: https://www.cbc.ca/news/canada/north/sheep-coat-colour-research-genetics-1.4124995
Here's what I'm talking about:
Sources:
https://en.wikipedia.org/wiki/Dall_sheep (Taxonomy and Genetics, paragraph 2-3)
https://yukonwildlife.ca/wildlife/thinhorn-sheep/11-20-thinhorn-mountain-sheep (first few paragraphs)
Actual genetic study by the University of Alberta:
A tale of two subspecies
DNA analysis rewrites the story of thinhorn sheep during the last ice age. Based on how the lineages were split, the division between the white Dall's sheep and the dark Stone's sheep is deeper than expected.
www.ualberta.ca
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