SHARK VS SHARK

PtychodusvsSqualicorax

Length, weight and bite evidence—plus context from a human, city bus and blue whale. Every number below carries its uncertainty with it.

ExtinctPtychodus mortoni×ExtinctSqualicorax pristodontus
QUICK VERDICT

Ptychodus is about 1.94× longer by these reference values.

Ptychodus uses a 9.7 m upper reference, compared with 5 m for Squalicorax. A clean mass ratio is not shown because at least one weight is not reliably reconstructed.

01

ON THE SAME SCALE

Human. Bus. Whale.
Pick your reference.

RELATIVE LENGTH · 0–24 METERS
APtychodusrecent reconstructions approach 9.7 m / 32 ft
BSqualicoraxestimated to about 5 m / 16 ft
REFAdult human1.8 m · about 80 kg

Length bars use upper comparison values and do not show body depth, tail proportion or typical adult size. A long thresher tail, for example, does not equal whale-shark body mass.

02

THE NUMBERS

Side by side.

MeasurePtychodusSqualicorax
Length referencerecent reconstructions approach 9.7 m / 32 ftestimated to about 5 m / 16 ft
Weight referenceNot reliably reconstructedNot reliably reconstructed
Bite forceNo defensible estimate usedUnknownNo defensible estimate usedUnknown
Timeabout 100–85 million years agoabout 85–66 million years ago
DietHard-shelled preyFishes, marine reptiles and carrion
03

WHAT THE DATA CAN SAY

Size is not the whole animal.

Length and weight

Ptychodus is represented by recent reconstructions approach 9.7 m / 32 ft; Squalicorax by estimated to about 5 m / 16 ft. A body outline is rare; length estimates can change with new fossils. Body length and ecology are reconstructed from incomplete fossil evidence.

Bite evidence

Ptychodus: Hard-prey specialization does not justify inventing a force number. Squalicorax: Bite traces show feeding, not maximum force.

Living versus extinct

At least one animal is known from fossils. Fossil length, weight and bite estimates depend on which living analogues and scaling equations researchers choose.

Ecology changes the matchup

Flattened crushing teeth—not knife-like teeth—defined this huge shark. Serrated teeth and bite traces show a broad, opportunistic diet.

04

TRACE THE CLAIMS

Sources and limits.

PtychodusPaleobiology DatabaseSqualicoraxPaleobiology DatabaseHow we standardize comparisonsRead the methodology →