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When asked about the deadliest shark to humans, most will say the great white.
Not surprising. Pop culture has turned them into fearsome predators.
The truth - they rarely attack.
The real answer is an interesting lesson on humans and survivorship bias.
Quick thread
Not surprising. Pop culture has turned them into fearsome predators.
The truth - they rarely attack.
The real answer is an interesting lesson on humans and survivorship bias.
Quick thread
1/ Great whites are closely related to tiger and bull sharks - two other types that also rarely attack humans.
The fatality rate in known attacks is 21.5% for bull, 26% for tiger, and a mere 16% for the great white.
They mostly mistake us for their main food source - seals.
The fatality rate in known attacks is 21.5% for bull, 26% for tiger, and a mere 16% for the great white.
They mostly mistake us for their main food source - seals.
2/ That’s one blind spot we already have - because the fatality rate is lower, the Great White leaves a lot more SURVIVORS. People who live to tell the tale of danger.
There’s another blind spot here though - the fatality rate above only talks about “documented” shark attacks..
There’s another blind spot here though - the fatality rate above only talks about “documented” shark attacks..
3/ One of the most dangerous sharks in the world is actually believed to be the Oceanic White Tip.
Unlike most sharks, they live in the water desert that is the open ocean, with less beaches and seals.
They have to eat pretty much whatever they can find.
That includes us.
Unlike most sharks, they live in the water desert that is the open ocean, with less beaches and seals.
They have to eat pretty much whatever they can find.
That includes us.
4/ In 1945, a US ship was shot down in the open ocean by a japanese submarine.
The water was full of white tip sharks - of the 1,195 crewmen originally aboard the ship, only 316 survived.
It represents the single biggest loss of life from a single ship in US naval history.
The water was full of white tip sharks - of the 1,195 crewmen originally aboard the ship, only 316 survived.
It represents the single biggest loss of life from a single ship in US naval history.
5/ This brings us to how humans make decisions - survivorship bias is all about indexing heavily on survivors.
If we only factor in survivors, we miss a key component of the problem. If we wanted to reduce shark attacks, our bias might lead us to protect against great whites.
If we only factor in survivors, we miss a key component of the problem. If we wanted to reduce shark attacks, our bias might lead us to protect against great whites.
6/ We’re influenced by public failure and end up optimizing for a small slice of reality.
More survivors can make something more dangerous simply because the volume of stories makes it stick.
We can’t be afraid of a tale if no one lives to tell it.
More survivors can make something more dangerous simply because the volume of stories makes it stick.
We can’t be afraid of a tale if no one lives to tell it.
7/ Not recognizing survivorship bias can lead to faulty decision making in many domains.
If you only pay attention to the Bill Gates and JK Rowlings of the world, you’ll never understand the trials and tribulations of those who never survived to celebrate a public success.
If you only pay attention to the Bill Gates and JK Rowlings of the world, you’ll never understand the trials and tribulations of those who never survived to celebrate a public success.
8/ So ask yourself next time you’re assessing risk - am I paying too much attention to the great white sharks and not enough to the oceanic white tips?
(Thread inspired by @farnamstreet piece: https://fs.blog/2020/10/sharks-survivorship-bias)
(Thread inspired by @farnamstreet piece: https://fs.blog/2020/10/sharks-survivorship-bias)
