There you go! I wasn't aware there were norms for dogs on panting and drooling. 
Actually there are, but dogs also adapt to heat just like humans, and just like humans if you lock them in a car on a hot die they will suffer and possibly die🤷🏼♂️
But what about cats, and Opossums, raccoons, birds, etc., are they all gonna wait to suffer until after the dogs do, or is it just that the author thinks will tug at peoples hearts more?