Waving a fiddler crab claw incurs measurable energetic costs

Evidence

13. Masatoshi Matsumasa and Minoru Murai were able to measure the energetic costs of fiddler crab claws in action by tracking changes in blood glucose (a sugar used to power activity) and blood lactate (a chemical by-product of metabolism and an indication of energy burned) as animals performed various behaviors. By measuring baseline lactate levels in resting animals, and comparing this to the elevated levels they detected during fights, Matsumasa and Murai showed that the energetic cost of waving a claw was substantial. — Emlen, Douglas J, Animal Weapons_ The Evolution of Battle, 767

Categorization

• SEED: Angle: weapons and displays are not free — measurable metabolic costs shape whether and how signals remain honest.
• XREF: connects to: Fiddler crabs have the largest relative weapons yet rarely fight; Waving a fiddler crab claw raises blood lactate measurably.; Costly claw muscle raises male fiddler crab resting metabolism nearly twenty percent — Emlen, Douglas J, Animal Weapons_ The Evolution of Battle, 303 (+2 more)

Related

• Waving a fiddler crab claw raises blood lactate measurably. (similarity 0.93)
• Costly claw muscle raises male fiddler crab resting metabolism nearly twenty percent (similarity 0.89)
• Fiddler crabs have the largest relative weapons yet rarely fight (similarity 0.88)
• Fiddler crabs use their oversized claws far more as signals than as weapons (similarity 0.87)
• Even resting male crabs pay high energy costs for big claw muscles (similarity 0.85)
• Fiddler crabs assess rival claw size and only approach equally-matched opponents. (similarity 0.79)
• Predation risk is a near-universal cost of elaborate weapons (similarity 0.79)
• Weapon size honestly signals fighting ability because growth tracks health and nutrition (similarity 0.79)

Broader Connections

• Predation risk is a near-universal cost of elaborate weapons #expands (0.45) — Emlen, Douglas J, Animal Weapons_ The Evolution of Battle, 307