# Genetic Insights Into Human‐Driven Hybridization, Cultural Shifts, and Ecological Consequences of Feral Pigs (Sus scrofa) in Hawai‘i

## TL;DR

The study examines the genetic makeup of feral pigs in Hawai‘i to understand their ancestry and the impact of European and Asian pig introductions on native ecosystems and culture.

## Contribution

The study provides new genetic evidence that European domestic lineages dominate contemporary feral pigs in Hawai‘i, challenging prior assumptions about their genetic uniqueness.

## Key findings

- Contemporary feral pigs in Hawai‘i show admixed ancestry from European and Asian pig lineages.
- European domestic lineages are the dominant genetic influence in current feral pig populations.
- The findings challenge previous claims of genetic uniqueness among Hawaiian feral pigs.

## Abstract

Feral pigs (
Sus scrofa
) in Hawai‘i pose a persistent threat to native biodiversity, endemic species, and culturally important resources. Polynesian pigs, or pua‘a, were brought to the Hawaiian Islands with Polynesian settlement in the mid‐1200s and represent part of the cultural legacy of Hawai‘i. Since the introduction of European pigs in 1778 and onward, the ancestral composition of contemporary animals has been debated, and conservation efforts for island endemic species have been challenged by tension between ecological destruction caused by contemporary feral pigs and the cultural importance of this animal. To inform this complex issue, our objective was to evaluate the genetic ancestry of contemporary feral pig populations across Hawai‘i to elucidate genetic remnants of past introductions. We used a high‐resolution single nucleotide polymorphism (SNP) array, providing a survey of the entire genome, to characterize ancestry, including hybridization of Polynesian pigs with global Asian and European lineages. We assembled a comprehensive reference set—representing the
S. scrofa
wild–domestic species complex—from which we queried 608 Hawaiian feral pig samples to quantify ancestral composition. Our results demonstrate that contemporary Hawaiian feral pigs have admixed ancestry influenced by European Heritage breeds and animals of Asian origin—potentially descending from initial Polynesian introductions. Importantly, we establish that European domestic lineages represent the dominant ancestral influence among contemporary feral pigs in Hawai‘i, which challenges previous claims of genetic uniqueness of these populations within the broader
S. scrofa
wild–domestic species complex.

Polynesian pigs were brought to the Hawaiian Islands with Polynesian settlement in the mid‐1200s and represent part of the cultural legacy of Hawai‘i. Yet, the introduction of European pigs since 1778 and onward has put into question the ancestral composition of contemporary animals, and conservation efforts have been challenged by tension between the ecological destruction caused by contemporary feral pigs and the cultural importance of this animal. Using a high‐resolution single nucleotide polymorphism array, we demonstrate the hybrid ancestry of contemporary feral pigs, characterized by a dominant ancestral influence from European domestic lineages. Our results challenge previous claims of genetic uniqueness of these populations and add to the body of literature focusing on this complex conservation topic.