Competition for reproduction drives evolution of nature’s biggest weapons

Evidence

In the animal world, extreme weapons are usually confined to specific, rare circumstances such as sit-and-wait hunting tactics, or within-colony division of labor. But another surprisingly potent phenomenon can lead to the evolution of exaggerated weapon sizes: competition. Nature’s biggest weapons decide the outcomes of battles over the chance to reproduce, the most precious commodity of all. — Emlen, Douglas J, Animal Weapons_ The Evolution of Battle, 136

Categorization

• XREF: connects to: The same three ingredients trigger weapon evolution across wildly divergent animal clades; Extreme skew in mating success drives arms-race escalation in weaponry; Markets and battlefields select among rifle designs like natural selection acts on weapons (+35 more)

Related

• Reproductive success, not survival, drives the largest animal weapons (similarity 0.93)
• Sexual selection can be far stronger than natural selection and drives weapon extremes (similarity 0.91)
• Weapon evolution needs both competition and economically defensible resources (similarity 0.90)
• Sexual selection drives weapons to extremes because payoffs for winners are enormous. (similarity 0.90)
• Weapons evolve only when reproductive benefits exceed costs (similarity 0.90)
• The same three ingredients trigger weapon evolution across wildly divergent animal clades (similarity 0.90)
• Markets and battlefields select among rifle designs like natural selection acts on weapons (similarity 0.90)
• Economic logic explains weapon evolution across virtually all animal species (similarity 0.89)
• Sexual selection stays directionally constant while physical natural selection oscillates (similarity 0.89)
• Weapon size in animal species is under stabilizing selection, not open-ended directional selection (similarity 0.89)
• Extreme weapons evolved independently across roughly three thousand species (similarity 0.89)
• Extreme skew in mating success drives arms-race escalation in weaponry (similarity 0.89)
• Natural selection usually favors modest weapon size because cost offsets benefit (similarity 0.89)
• Social competition environments evolve in tandem with weapons, unlike fluctuating physical environments (similarity 0.89)
• Specific ecological circumstances must align before weapon arms races begin (similarity 0.89)

Broader Connections

• Sexual selection can be far stronger than natural selection and drives weapon extremes #corroborates (0.85) — Emlen, Douglas J, Animal Weapons_ The Evolution of Battle, 177
• Weapons evolve only when reproductive benefits exceed costs #qualifies (0.70) — Emlen, Douglas J, Animal Weapons_ The Evolution of Battle, 199
• Scarcity of suitable feeding sites drives weapon evolution in harlequin beetles #exemplifies (0.65) — Emlen, Douglas J, Animal Weapons_ The Evolution of Battle, 206
• Social competition environments evolve in tandem with weapons, unlike fluctuating physical environments #expands (0.60) — Emlen, Douglas J, Animal Weapons_ The Evolution of Battle, 182
• Economic logic explains weapon evolution across virtually all animal species #expands (0.55) — Emlen, Douglas J, Animal Weapons_ The Evolution of Battle, 198