THE ANIMAL FILES

European lobster

Homarus gammarus

Two claws, two different kinds of work.

The European lobster pairs a sturdy external skeleton with distinctly unequal claws.[1]

Follow the evidence ↓
European lobster
Image: Bart Braun · Commons · Public domain
Claws with different jobs
A crusher and a cutter[1]
Growing out of armour
Growth requires moulting[1]
From currents to crevices
Drifting larvae, bottom-living adults[1]

Claws with different jobs

One large claw has rounded working surfaces suited to crushing; the other has sharper edges useful for holding or tearing.[1]

Growing out of armour

The hard exoskeleton must be shed as the lobster grows. Young animals moult more frequently than large individuals.[1]

From currents to crevices

Females carry eggs beneath the abdomen. After hatching, larvae enter surface waters and drift with currents before later adopting a bottom-living form. Adults favour firm substrates and shelter in holes or crevices, coming out at night to eat bottom-dwelling invertebrates.[1]

A COMMON MIX-UP

Is the living lobster necessarily bright red?

No. Its living exoskeleton is generally blue above. The familiar cooked red colour results from changes to the pigment-protein association when heated.[1]

TRY A LITTLE REASONING

Why might an adult shelter survey miss the youngest lobsters?

Reveal the explanation

Early larvae drift in the water rather than occupying adult crevices. The same species changes habitat use as it develops, so one survey location cannot represent every stage.[1]

Sources & editorial notes

Adapted and translated from the cited Wikipedia revisions, with source-linked reasoning. Image credit and licence are listed separately above.

Adapted and translated from Wikipedia contributors; exact revisions are linked below. CC BY-SA 4.0

  1. Wikipedia contributors — European lobster (cited revision)
  2. NCBI Taxonomy — Homarus gammarus

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