Table 2. Human encouragement and responses to tail-chasing in dogs on YouTube™.

Human response to tail-chasing (n = number of valid videos)	Proportion of videos (excluding videos with missing values)	Examples or synonyms (where relevant)
Human behaviour	-	-
Laughter	199/362 (55.0%)	Female: 66.4%; male 18.6%; both sexes: 15.0%
Verbal encouragement	119/362 (32.9%)	“Get your tail!”, “Get it!”
‘Growling’ at dog	6/321 (1.9%)
Physical manipulation	74/371 (19.9%)	Placing the tail in the mouth, pulling or pinching the tail, waving the tail near the dog's face, pushing the hindquarters
Tail attachment	14/371 (3.8%)	Attaching hair bands, dog toys or treats, a bottle, a section of plastic piping, or string to the tail
Verbal praise	12/362 (3.3%)	“Good dog”, “Good girl/boy”, and other variants
Physical praise	2/371 (0.6%)	Patting or stroking the dog, or feeding it a treat, after a chasing bout
Uploader description	-	-
‘Funny’	149/253 (58.9%)	“Funny”, “haha”, “lol” (laugh out loud), “hilarious”, “comedy”, “humour”, “XD” (a laughing emoticon), “lmao” (laugh my ass off)
‘Crazy’	65/250 (26.0%)	“Crazy”, “mad” (but not “gets mad” or “mad at” as these indicate perceived anger), “insane”, “mental”, “maniac”, “nuts”, “psycho”, “nutcase”
‘Cute’	47/250 (18.8%)	“Cute”, “cutie”, “sweet”, “aww”, “adorable”
‘Stupid’	38/251 (15.1%)	“Stupid”, “retard/retarded”, “nerd”, “dumb”, “duh/doh”, “dumbass”, “dopey”, “idiot”, “moron”
‘Silly’	28/250 (11.2%)	“Silly”, “Goofy”
‘Fun’	19/250 (7.6%)	“Fun”, “amusing”, “entertainment”
‘Play’	12/250 (4.8%)	“Play”, “playing”, “game”, “playful”
‘Dizzy’	11/250 (4.4%)	“Dizzy”
‘Weird’	10/250 (4.0%)	“Weird”
‘Tricks’	8/249 (3.2%)	Tail-chasing is the dog's “party trick”
‘Awesome’	8/250 (3.2%)	“Awesome”, “cool”, “amazing”, “wow”
‘Bored’	5/250 (2.0%)	“Bored”
‘Hyper’	4/250 (1.6%)	“Hyper”, “hyperactive”, “energetic”
Other	N/A	Angry, classic, clever, confused, crack up, curious, dirty, enjoy, freak, frenzy, frustrated, inner battle, itchy, loser, nerd, nice, obsessed (x 2), possessed, serious problems, smart, spaz, tipsy, torture, wild, wrong, “I love that my dog actually chases her tail”
Explanations given	N/A	[The dog…] “loves/likes to tail-chase” (x6), “hates his tail”, is “entertaining herself”, is “having fun”, is “either bored or has high cholesterol”, “enjoys the dizziness”, does it “out of dominance”, “puts on a little show”, “needs prozac”, “chases on command” (x2), is “still a puppy”, “hasn't figured [his tail] is connected to him”, is showing “typical dog behaviour”, is playing “his favourite game”
Viewer comments	-	-
‘Funny’	64/138 (46.0%)	As for ‘Uploader description’, plus “hilarious”
‘Cute’	58/138 (41.7%)	As for ‘Uploader description’
‘Awesome’	16/138 (11.5%)	As for ‘Uploader description’, plus “impressive”
‘Stupid’	11/138 (7.9%)	As for ‘Uploader description’, plus “daft”, “not that smart”
‘Crazy’	4/138 (3.6%)	As for ‘Uploader description’, plus “bonkers”
Other	N/A	“Great” (x2), “excellent”, “nice” (x3), “priceless”, “entertaining”, “weird”, “gay”, “fun” (x2), “cruel”, “animal abuse”, “I wonder why they do that”, “My dog does/did that too” (x7), “My dog bites his tail to the point of bleeding”, “My dog spins/chases faster than yours” (x4), “Dog chasing tail never gets old”, “I want your dog”, “I've never seen a dog do that”, “I feel bad for him”, “repetitive behaviours need to be checked by a vet”, “I love it when dogs and cats do that”
Explanations given	N/A	[The dog…] has “high cholesterol” (x2), has “canine compulsive disorder”, is in “pain/discomfort”, has “Schizophrenia”, needs “the doggie chiropractor”, is “happy”, needs “toys”, “doesn't know [the tail] is part of their body yet”, has an “itchy tail”, has “worms”, is “hyper”, is “bored”, is “showing off”, has “a flea stuck in his tail”

The percentages of videos are arranged in order of magnitude for each general category. The words that were accepted as valid synonyms for comment categories were shown. These were accepted only if they were consistent within the context of the whole comment, e.g. a comment was not included in the counts for ‘funny’ if the comment actually stated that the video was ‘not funny’, even though the keyword was present in the comment.