Weapons are better signals than body size because they vary from zero to enormous

Evidence

First, they’re vastly more variable than other elements of an animal’s arsenal. No elk stand zero inches tall, for example. All elk have bodies and muscles, but there are plenty without antlers. Weapon size spans all the way from zero to enormous, resulting in a bigger range from male to male than in other body parts. It’s far easier to discern six-foot-long antlers from a pair of six-inch spikes, than it is to tell that one male stands a few inches taller than the other. Even subtle differences in the body sizes or fighting abilities of males become amplified into pronounced differences in the relative sizes of their weapons. — Emlen, Douglas J, Animal Weapons_ The Evolution of Battle, 353

Categorization

• XREF: Amplification of small differences into large detectable ones is the same logic as handicap-signaling honesty guarantees elsewhere in the field. — connects to: Weapon costliness keeps signals honest by excluding weaker males; Extreme weapon size is relative to body size, not absolute — Emlen, Douglas J, Animal Weapons_ The Evolution of Battle, 3; Weapons evolved as signals so males could predict fight outcomes before risking battle — Emlen, Douglas J, Animal Weapons_ The Evolution of Battle, 370 (+1 more)

Related

• Extreme weapon size is relative to body size, not absolute (similarity 0.87)
• Weapon growth widens the gap between the best- and worst-armed males. (similarity 0.87)
• Weapon size in animal species is under stabilizing selection, not open-ended directional selection (similarity 0.86)
• Weapons evolved as signals so males could predict fight outcomes before risking battle (similarity 0.86)
• Weapon size should track resource availability more than any mandatory body part (similarity 0.86)
• Weapon costliness keeps signals honest by excluding weaker males (similarity 0.86)
• Weapon size honestly signals fighting ability because growth tracks health and nutrition (similarity 0.86)
• Military size honestly signals a state’s fighting strength just as animal weapons do (similarity 0.85)
• Extreme weapon size faces stabilizing, not open-ended, selection in real populations (similarity 0.85)
• Weapon expense is what keeps signals of fighting ability honest (similarity 0.85)
• Only a minority of males can afford to build full-size weapons (similarity 0.84)
• Big weapons only benefit males with the reserves to wield them effectively (similarity 0.84)
• Variation in animal weapon size is explainable by species ecology and behavior. (similarity 0.84)
• Growing large weapons diverts resources and stunts other body parts (similarity 0.84)
• Natural selection usually favors modest weapon size because cost offsets benefit (similarity 0.83)

Broader Connections

• Extreme weapon size is relative to body size, not absolute #expands (0.85) — Emlen, Douglas J, Animal Weapons_ The Evolution of Battle, 3
• Weapons evolved as signals so males could predict fight outcomes before risking battle #corroborates (0.70) — Emlen, Douglas J, Animal Weapons_ The Evolution of Battle, 370