ZEBRAS, UNHAPPY MARRIAGES, AND THE ANNA KARENINA PRINCIPLE: Why Were Most Big Wild Mammal Species Never Domesticated?
The Anna Karenina Principle in Domestication
The Anna Karenina principle asserts that a multitude of factors must align for success; failure in any one can lead to failure overall. This concept is applied to explain why certain wild animals are domesticate-able while others are not. Despite apparent suitability, many species like zebras and peccaries remain undomesticated, mostly confined to Eurasia. The major domestic animals that have been widely integrated into human societies include cows, sheep, goats, pigs, and horses, among others.
Crucial Roles of Domesticated Mammals
Domesticated mammals have been essential to human societies offering resources like meat, milk, fertilizer, and labor for transport and agriculture. While small animals like birds and insects have also been domesticated, large mammals indirectly affected human development with significant contributions.
Limitations in Domestication
The attempted domestication of many species often failed due to specific limitations inherent to each species:
- Diet: Many animals have highly specialized diets that do not lend themselves to broad-scale feeding practices necessary for domestication.
- Growth Rate: Some animals grow too slowly to be practical for domestication, like elephants and gorillas.
- Captive Breeding Difficulties: Some species do not breed well in captivity, as seen with cheetahs which require extensive conditions to reproduce.
- Nasty Disposition: Animals with dangerous or aggressive behaviors, such as grizzly bears and African buffaloes, prove too hazardous to domesticate.
- Panic Tendency: Species prone to panic, like many deer, cannot be easily controlled or kept in enclosures as they injure themselves or die from stress.
- Social Structure: Effective domesticates often come from species with a social structure compatible with herding and a dominance hierarchy that humans can integrate into.
Modern Domestication Efforts
Despite modern scientific advancements, no new large mammals have been domesticated successfully in recent times. Historical attempts and contemporary efforts reflect that only select species meet the multifaceted criteria needed for domestication. Even species with potential advantages like the disease-resistant eland in Africa have not been domesticable to the extent that they are economically viable.
Geographic and Biological Factors
The uneven distribution of domesticable animals across continents has significantly affected human history. Eurasia, with the most diverse and largest landmass, had the highest number of potential species suitable for domestication. This advantage was not shared by other continents like the Americas or Australia, which either faced massive extinctions of potential domesticate species or lacked large herbivores conducive to domestication.
Conclusion
Only a small subset of the world's large wild mammals have been domesticated due to stringent and multi-layered requirements. These animals have profoundly shaped the societies that had access to them, contributing to disparities in the development and progression of civilizations across different continents. The domestication of animals has historically been bound by biological, ecological, and behavioral factors that dictate the feasibility of integrating wild species into human society.