# Alfred Russel Wallace on the Aru Islands

## Overview

Alfred Russel Wallace visited the Aru Islands (in present-day eastern Indonesia, in the Maluku province) from January to July 1857, during his eight-year expedition through the Malay Archipelago (1854–1862). The visit was one of the most significant and productive periods of his entire journey, both in terms of specimen collection and in shaping his thinking about biogeography and natural selection.

## Context and Motivation

Wallace had long desired to visit the Aru Islands because of their proximity to New Guinea and their reputation for producing Birds of Paradise, which were highly valued in the European specimen trade. The islands sat on the Australian side of what would become known as the Wallace Line (though he had not yet fully formulated this concept), and he expected to find fauna with strong Australasian affinities—which indeed he did.

## Getting There

Wallace sailed to Aru from Macassar (Makassar) in Sulawesi. He traveled on a native trading prau during the monsoon season, which was the traditional time for Malay and Bugis traders to make the voyage to Aru to trade for bird of paradise skins, trepang (sea cucumber), pearls, and other goods. The journey took a number of weeks.

## Geography of the Aru Islands

The Aru Islands are a group of low-lying islands separated by narrow channels that Wallace recognized were essentially drowned river valleys—evidence that the islands had once been connected to New Guinea as part of a larger landmass during periods of lower sea level. This observation was important to his biogeographical thinking. He noted that the islands were composed largely of coralline limestone and were heavily forested.

## Bases of Operation

Wallace established himself at several locations during his stay:

- **Dobbo** (also spelled Dobo): The main trading settlement on the island of Wamma, where traders from across the archipelago gathered during the trading season. Wallace described it as a lively, cosmopolitan, yet remarkably orderly and peaceful settlement despite having no formal government or police. He marveled at the fact that diverse peoples—Bugis, Ceramese, Chinese, and others—coexisted and conducted trade with minimal conflict, which he used as evidence that complex government was not always necessary for social order.

- **Interior villages**: Wallace made expeditions into the forested interior of the main islands, staying in native houses and employing local hunters and assistants.

## Natural History Collections

The Aru Islands proved extraordinarily productive for Wallace:

### Birds of Paradise
This was where Wallace first observed living Birds of Paradise in their natural habitat. He was particularly entranced by the **Greater Bird of Paradise** (*Paradisaea apoda*) and the **King Bird of Paradise** (*Cicinnurus regius*). He described their display behaviors with great excitement and emotion—famously writing about how the sight of the Greater Bird of Paradise displaying was one of the most memorable experiences of his life, and reflecting on how few European eyes had ever witnessed such a spectacle. He obtained numerous specimens.

### Other Birds
He collected many other bird species with Australasian affinities, including parrots, cockatoos, lories, and brush turkeys (megapodes), confirming that Aru's fauna was fundamentally different from that of the western part of the archipelago.

### Insects
Wallace collected extensively, including many fine butterflies and beetles. He found large and spectacular birdwing butterflies.

### Mammals
He noted the presence of marsupials (such as cuscuses) rather than placental mammals, further confirming the Australasian character of the fauna.

## Biogeographical Significance

The Aru Islands provided crucial evidence for Wallace's developing ideas about the sharp faunal boundary between Asian and Australian biogeographical realms. The fauna was overwhelmingly Australo-Papuan in character, despite the islands' relative proximity to some islands with Asian fauna. This supported his argument that deep oceanic channels represented ancient barriers to dispersal, while shallow seas (like those connecting Aru to New Guinea) indicated former land connections.

## Interactions with Indigenous People

Wallace described the indigenous Aru Islanders as Papuan in character—related to the peoples of New Guinea. He wrote about their customs, appearance, and way of life with characteristic Victorian-era ethnographic interest. He employed local people as hunters and guides and had various interactions with village communities during his interior excursions.

## Hardships

Wallace endured significant difficulties during his time on Aru, including:
- Insect pests (ants and other creatures invading his specimens)
- Difficult travel conditions through swampy terrain and narrow waterways
- Illness (he suffered from fever at various points)
- Challenges in managing local helpers and obtaining adequate food

## Connection to the Theory of Natural Selection

Wallace's time on the Aru Islands was roughly one year before his famous insight about natural selection (which came during a fever on Halmahera/Ternate in early 1858). However, the patterns he observed on Aru—the distribution of species, their relationships to New Guinea forms, and the evidence of variation—were undoubtedly part of the accumulating body of observations that fed into his theoretical breakthrough.

## Written Accounts

Wallace wrote about the Aru Islands extensively in:
- **"The Malay Archipelago"** (1869): Several chapters are devoted to Aru, and they are among the most vivid and celebrated passages in the book.
- **Scientific papers**: He published descriptions of new species and biogeographical observations based on his Aru collections.
- **Letters**: He wrote to his agent Samuel Stevens and to others (including Henry Walter Bates) about his Aru experiences, and Stevens published extracts in journals to maintain interest in Wallace's work.

## Legacy

Wallace's Aru collections were enormous—he gathered thousands of specimens including many species new to science. The specimens were sold through his agent Stevens to collectors and museums, helping to fund his continued travels. His descriptions of Aru remain among the most compelling sections of *The Malay Archipelago* and helped cement the book's reputation as one of the finest works of scientific travel literature in the 19th century.

The Aru Islands visit represents Wallace at the height of his powers as a field naturalist—combining meticulous collecting, keen ecological observation, broad biogeographical thinking, and vivid descriptive writing.
