Tunneling behavior predicts horn evolution in dung beetles
Evidence
We found that tunneling behavior strongly predicted the evolution of horns, and when species switched from tunneling to ball-rolling behavior, they subsequently lost their male horns. — Emlen, Douglas J, Animal Weapons_ The Evolution of Battle, 713
Categorization
- XREF: Concrete example of the environment-ecology constraint on weapon evolution, central to the book’s argument that ecology limits armament — connects to: Tunneling dung beetles guard burrow entrances and evolve horns; rollers do not — Emlen, Douglas J, Animal Weapons_ The Evolution of Battle, 222; Beetle horn presence depends on post-arrival behavior, not the dung itself — Emlen, Douglas J, Animal Weapons_ The Evolution of Battle, 218; No ball-rolling dung beetle species has evolved horns despite constant fighting (+2 more)
- corroborated: 2 independent passages support this claim — Emlen, Douglas J, Animal Weapons_ The Evolution of Battle, 713
Related
- Tunneling dung beetles guard burrow entrances and evolve horns; rollers do not (similarity 0.95)
- No ball-rolling dung beetle species has evolved horns despite constant fighting (similarity 0.93)
- Dung beetle horns evolved and were lost repeatedly across their history (similarity 0.91)
- Beetle horn presence depends on post-arrival behavior, not the dung itself (similarity 0.89)
- Tunnel-bound fights give longer horns a decisive performance advantage (similarity 0.87)
- Smaller-horned males usually lose escalated dung beetle fights (similarity 0.87)
- Tunnel dwellers fight successive duels and evolve weapons; open-ground species scramble without them. (similarity 0.84)
- Dung beetles offer the ideal study system for extreme weapon evolution. (similarity 0.83)
- Burrow-guarding constrains fights to duels and drives weapon evolution (similarity 0.82)
- Horn growth is nine times more nutrition-sensitive than genitalia in beetles (similarity 0.79)
- Beetle horns can reach 30 percent of male body weight (similarity 0.79)
- Beetle horns can be impressively large yet nearly cost-free to produce and use (similarity 0.79)
- Closely related beetle species can differ sharply in horn possession (similarity 0.78)
Broader Connections
- Tunneling dung beetles guard burrow entrances and evolve horns; rollers do not
#expands(0.80) — Emlen, Douglas J, Animal Weapons_ The Evolution of Battle, 222 - Tunnel-bound fights give longer horns a decisive performance advantage
#expands(0.80) — Emlen, Douglas J, Animal Weapons_ The Evolution of Battle, 224 - No ball-rolling dung beetle species has evolved horns despite constant fighting
#corroborates(0.70) - Beetle horn presence depends on post-arrival behavior, not the dung itself
#expands(0.60) — Emlen, Douglas J, Animal Weapons_ The Evolution of Battle, 218 - Smaller-horned males usually lose escalated dung beetle fights
#expands(0.60) — Emlen, Douglas J, Animal Weapons_ The Evolution of Battle, 402