Alfred Russel Wallace spent about six months in the Aru Islands (January to July 1857), and this period was one of the most significant of his eight-year expedition through the Malay Archipelago. Here's what we know about his time there:

## Getting There and Geography
The Aru Islands are located in eastern Indonesia, southwest of New Guinea. Wallace reached them after a difficult journey from Macassar (now Makassar), traveling on a native prau (boat). The islands were remote and rarely visited by Europeans at the time, making them particularly attractive for collecting novel species.

## Base of Operations
Wallace established his headquarters at Dobbo, a trading settlement on a small island called Wamma, which was the commercial center of the Arus. From there, he made collecting expeditions to various parts of the archipelago, including the larger islands of the mainland group.

## Natural History Discoveries
The Aru Islands proved extraordinarily productive for Wallace:

- **Birds of Paradise**: He obtained fine specimens of the Great Bird of Paradise (Paradisaea apoda), which was one of his major goals. He was among the first naturalists to observe these birds' behavior in the wild.

- **King Bird of Paradise**: He collected specimens of the King Bird of Paradise (Cicinnurus regius), describing their remarkable beauty and courtship displays.

- **Butterflies**: He discovered numerous butterfly species, including spectacular birdwing butterflies.

- **Beetles and Insects**: The islands yielded an enormous variety of insects, many new to science.

## Living Conditions and Challenges
Wallace faced numerous difficulties:
- He lived in a small house made of bamboo and palm leaves
- Dealt with tropical heat, humidity, and frequent rain
- Suffered from bouts of illness
- Had to manage difficult relations with his assistants and local guides
- Faced occasional food shortages and the challenges of preserving specimens in tropical conditions

## Biogeographical Significance
The Aru fauna showed strong affinities with New Guinea rather than with the western Indonesian islands. Wallace noted that despite being separated by deep water channels, the Arus shared many species with New Guinea, including:
- Cassowaries
- Birds of Paradise
- Many types of parrots and pigeons
- Particular butterfly genera

This observation contributed to his developing ideas about biogeographical regions and what would later be known as the Wallace Line.

## Indigenous Peoples
Wallace extensively documented the Aru Islanders, noting:
- Their Papuan characteristics, distinct from the Malay peoples to the west
- Their trading relationships with Bugis and Macassar merchants
- Their hunting and fishing techniques
- Their material culture and boat-building skills

## Commercial Context
Dobbo was a seasonal trading post where merchants from across the region came to trade for:
- Pearls and mother-of-pearl
- Trepang (sea cucumbers)
- Bird of Paradise plumes
- Tortoiseshell

Wallace observed this trade closely and used these commercial networks to facilitate his own collecting.

## Written Record
Wallace's experiences in the Aru Islands are vividly described in several chapters of his book "The Malay Archipelago" (1869). His accounts include:
- Detailed natural history observations
- Ethnographic descriptions
- Personal adventures and misadventures
- Philosophical reflections on nature and human society

## Scientific Impact
The collections from the Aru Islands were particularly valuable:
- Hundreds of bird specimens, including many new species
- Thousands of insects
- These specimens were sent back to England where they were sold to museums and private collectors, providing Wallace with crucial income
- The observations contributed to his evolutionary thinking and biogeographical theories

The Aru Islands represented one of Wallace's most successful collecting locations, both in terms of the quantity and quality of specimens obtained, and in the insights they provided into the distribution of species across the archipelago. His time there exemplified both the rewards and challenges of natural history collecting in remote tropical regions during the Victorian era.
