They were hunted almost to extinction at one point. No one is quite sure if that's what started the idea that they never really existed, or if that story was spread on purpose to limit the demand for their pelts.
There's a taxidermy Lowland Haggis in the Kelvingrove Museum in Glasgow (the google algorithm that tags photos saved to your account has clearly improved - I used to be able to find this by searching "dog"

) and a plaque in the park nearby to mark the place it was shot, as it was the last of its subspecies.
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