Growing large weapons diverts resources and stunts other body parts

Evidence

As weapons get big they also get expensive, and males with the longest horns now had stunted eyes. By the end of the experiment, males selected for longer horns had eyes that were 30 percent smaller than males selected for shorter horns. Stunted growth arises because of a limited availability of nutrients. Tissues require energy and materials to grow, and allocating resources to the production of one structure can mean that those same resources are no longer available for the growth of another. — Emlen, Douglas J, Animal Weapons_ The Evolution of Battle, 295

Categorization

• XREF: Connects to the reader’s knowledge of energetic trade-offs in evolution; the compensation logic parallels trade-offs in other arms-race contexts in this book and in evolutionary biology generally. — connects to: Weapons in arms races get so big they impair other bodily functions; Some elaborate animal weapons are astonishingly cheap to produce and carry; Bigger weapons usually fail because their costs outweigh their benefits (+9 more)

Related

• Weapons in arms races get so big they impair other bodily functions (similarity 0.94)
• Arms-race weapon growth makes resource trade-offs drastically impair body functions (similarity 0.93)
• Weapon growth is far more resource-sensitive than other body parts (similarity 0.90)
• Weapon size should track resource availability more than any mandatory body part (similarity 0.89)
• Infections shrink weapon growth because immunity consumes the same resource pool (similarity 0.89)
• Weapons grow late because development prioritizes mandatory survival expenses first (similarity 0.89)
• Early survival advantages compound into huge adult differences in weapon resources (similarity 0.87)
• Big weapons only benefit males with the reserves to wield them effectively (similarity 0.87)
• Animal weapons evolved to extremes far beyond practical size (similarity 0.86)
• Weapon growth widens the gap between the best- and worst-armed males. (similarity 0.86)
• Bigger weapons usually fail because their costs outweigh their benefits (similarity 0.86)
• Reproductive success, not survival, drives the largest animal weapons (similarity 0.86)
• Weapon size in animal species is under stabilizing selection, not open-ended directional selection (similarity 0.85)
• Weapons evolve only when reproductive benefits exceed costs (similarity 0.85)
• Predator weapons stay small because larger ones hinder hunting (similarity 0.85)

Broader Connections

• Arms-race weapon growth makes resource trade-offs drastically impair body functions #expands (0.70) — Emlen, Douglas J, Animal Weapons_ The Evolution of Battle, 296
• Weapon growth is far more resource-sensitive than other body parts #expands (0.60) — Emlen, Douglas J, Animal Weapons_ The Evolution of Battle, 340
• Early survival advantages compound into huge adult differences in weapon resources #expands (0.55) — Emlen, Douglas J, Animal Weapons_ The Evolution of Battle, 334