SHARK VS SHARK

CladoselachevsSqualicorax

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

ExtinctCladoselache fyleri×ExtinctSqualicorax pristodontus
QUICK VERDICT

Squalicorax is about 2.8× longer by these reference values.

Squalicorax uses a 5 m upper reference, compared with 1.8 m for Cladoselache. 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
ACladoselacheabout 1.8 m / 6 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.

MeasureCladoselacheSqualicorax
Length referenceabout 1.8 m / 6 ftestimated to about 5 m / 16 ft
Weight referenceNot reliably reconstructedNot reliably reconstructed
Bite forceNo defensible estimate usedUnknownNo defensible estimate usedUnknown
Timeabout 370 million years agoabout 85–66 million years ago
DietSmall fishesFishes, marine reptiles and carrion
03

WHAT THE DATA CAN SAY

Size is not the whole animal.

Length and weight

Cladoselache is represented by about 1.8 m / 6 ft; Squalicorax by estimated to about 5 m / 16 ft. Calling it a modern-style shark hides major evolutionary distance. Body length and ecology are reconstructed from incomplete fossil evidence.

Bite evidence

Cladoselache: No usable maximum-force model exists. 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

It was an early shark-like chondrichthyan with a streamlined body. Serrated teeth and bite traces show a broad, opportunistic diet.

04

TRACE THE CLAIMS

Sources and limits.

CladoselacheSmithsonian National Museum of Natural HistorySqualicoraxPaleobiology DatabaseHow we standardize comparisonsRead the methodology →