The face that sank the Essex: potential function of the spermaceti organ in aggression
| Autor: | Stephen M. Deban, Jason J. Otterstrom, David R. Carrier |
|---|---|
| Rok vydání: | 2002 |
| Předmět: |
Male
Physiology Melon Zoology Aquatic Science Body size Models Biological Species Specificity Sperm whale medicine Animals Whaling Molecular Biology Phylogeny Ecology Evolution Behavior and Systematics Sex Characteristics biology Ecology Aggression Whales Spermaceti organ Animal Structures food and beverages biology.organism_classification Sperm Sexual dimorphism Insect Science Body Constitution Female Animal Science and Zoology Cetacea medicine.symptom |
| Zdroj: | Journal of Experimental Biology. 205:1755-1763 |
| ISSN: | 1477-9145 0022-0949 |
| DOI: | 10.1242/jeb.205.12.1755 |
| Popis: | SUMMARY `Forehead to forehead I meet thee, this third time, Moby Dick!' [Ahab (Melville, 1851)] Herman Melville's fictional portrayal of the sinking of the Pequodwas inspired by instances in which large sperm whales sank whaling ships by ramming the ships with their heads. Observations of aggression in species of the four major clades of cetacean and the artiodactyl outgroup suggest that head-butting during male—male aggression is a basal behavior for cetaceans. We hypothesize that the ability of sperm whales to destroy stout wooden ships, 3-5 times their body mass, is a product of specialization for male—male aggression. Specifically, we suggest that the greatly enlarged and derived melon of sperm whales, the spermaceti organ, evolved as a battering ram to injure an opponent. To address this hypothesis, we examined the correlation between relative melon size and the level of sexual dimorphism in body size among cetaceans. We also modeled impacts between two equal-sized sperm whales to determine whether it is physically possible for the spermaceti organ to function as an effective battering ram. We found (i) that the evolution of relative melon size in cetaceans is positively correlated with the evolution of sexual dimorphism in body size and (ii) that the spermaceti organ of a charging sperm whale has enough momentum to seriously injure an opponent. These observations are consistent with the hypothesis that the spermaceti organ has evolved to be a weapon used in male—male aggression. |
| Databáze: | OpenAIRE |
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