Sharks have survived five mass extinctions, which means they've been collecting trivia material since before anything had bark. Cover the answers, lock in each guess, and keep score — and be honest about the one you get wrong because of the movies.

Which came first: sharks or trees?

Sharks — by tens of millions of years. Sharks go back roughly 450 million years; true trees arrived around 385 million years ago.

How many bones does a shark have?

Zero — the entire skeleton is cartilage, the same flexible stuff as your ears and nose.

What is the largest fish in the sea?

The whale shark — a gentle filter-feeder that can reach around 40 feet and eats almost nothing bigger than plankton.

How old can a Greenland shark get?

Centuries — a 2016 study dated one at a minimum of about 272 years, possibly closer to 400, making it the longest-lived vertebrate known.

What is the fastest shark?

The shortfin mako — with burst estimates in the neighborhood of 45 mph, fast enough to launch clear out of the water.

What is shark skin actually made of?

Tiny tooth-like scales called dermal denticles — dried shark skin was once literally used as sandpaper.

How many teeth can a shark go through in a lifetime?

Tens of thousands — they grow in conveyor-belt rows, with new ones rotating forward as old ones fall out.

What can a shark detect with the pores dotted around its snout?

Electricity — the ampullae of Lorenzini sense the faint electrical fields of living things, including prey hiding motionless under sand.

Do sharks really die if they stop swimming?

Mostly myth — many species can rest on the bottom and pump water over their gills; only some, like great whites, must keep moving to breathe.

Which shark can swim in fresh water — and how far inland has it gotten?

The bull shark, which has been found roughly a thousand miles up the Mississippi River, as far as Illinois.

What happens if you flip a shark upside down?

It can slip into a trance called tonic immobility — a trick orcas have learned to exploit when hunting great whites.

How big was megalodon, the largest shark ever?

Estimates run to roughly 50–60 feet, with teeth the size of a human hand — and it went convincingly extinct around 3.6 million years ago, documentaries notwithstanding.

Why has no aquarium ever displayed an adult great white long-term?

They refuse captivity — they stop eating and ram the walls. The record is a juvenile kept 198 days at Monterey Bay in 2004–05 before release.

In a typical year, how does the shark-versus-human scoreboard read?

Lopsided — unprovoked shark bites kill perhaps five to ten people worldwide, while humans kill an estimated 100 million sharks, mostly for fins and as bycatch.

Sit with the Greenland shark for a second: the oldest one measured was likely swimming before the United States existed — and it may still be out there, unimpressed by everything that's happened since.