What would you do if you saw a shark out on the water? Australian grom Alex Hayes was apparently out on his paddle board last week when he spotted a great white swimming right beneath him.

"At first I freaked," he wrote on Instagram, "and then I saw that he was a chiller and just cruisin'..." So he snapped this insane selfie. As you do.

A photo posted by Alex Hayes (@alexhayess) on

"Changes my perspective about sharks, they aren't all dangerous" he wrote.

Perhaps unsurprisingly, the image went viral almost immediately. Australian website Pedestrian reckoned Alex's reaction was "a contender for the title of 'The Most Aussie Thing Anyone Has Said, Ever'".

But was the picture too good to be true? As the image spread, various eagle-eyed internet users noticed a striking similarity between the great white in the picture and this one, from a South African website.

Photo: becomingyou.co.za

Challenged on the claim, Alex told Pedestrian: "Ya got me. It's pretty funny. I didn't really expect anything like this to happen so it was a bit of a surprise."

He and a mate "had a little play around with this photo of a shark and thought it was a bit obvious and uploaded it for a good laugh... Now I know what it feels like telling a kid that Santa Claus isn't real."

But he said he stood by his comments about sharks not being dangerous, adding. "I've always loved sharks, and I always kick up a stink when I see people wanting to 'cull the sharks' and that they are all 'man-eaters', when it's clearly their ocean and we are entering their home so we just have to respect that!"

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