Alfred Russel Wallace’s time on the Aru Islands (Kepulauan Aru, in what is now Maluku, Indonesia) was one of the most important—and most vivid—episodes of his eight-year expedition through the Malay Archipelago (1854–1862). Aru gave him (1) some of his most famous specimens, especially birds-of-paradise; (2) firsthand, almost “textbook” evidence for the deep biogeographic split between Asian and Australian-type faunas; and (3) a close look at a trading frontier where Malay, Chinese, and Papuan worlds met.

Below is a detailed account of what is known from Wallace’s own writings (especially *The Malay Archipelago*, 1869) and later historical scholarship.

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## 1) When and why Wallace went to Aru
**Timing:** Wallace visited Aru in the late 1850s (during the middle period of his Malay Archipelago travels). He stayed **for several months**, using the islands as a collecting base and making excursions into forests and riverine/swamp interiors.

**Primary motivation:** He went to Aru largely because it was a renowned source of:
- **Birds-of-paradise** (high scientific value and high commercial value in Europe)
- Other New Guinea–affiliated birds and insects
- Australasian-type mammals (marsupials), which were rare or absent on islands further west

Wallace was financing his scientific work by collecting and selling natural history specimens (birds, insects, shells, etc.) to agents and collectors back in Britain. Aru was, for him, both scientifically exciting and economically strategic.

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## 2) What Aru was like (as Wallace encountered it)

### Geography and habitat
Wallace emphasized that Aru is **low-lying**, with extensive:
- **Swamps**
- **Mangroves**
- **Sago-rich wetlands**
- Forested patches (often difficult to access because of waterlogged ground)

Aru did not look like a dramatic volcanic island; instead it felt like a **flat, watery extension of New Guinea**—an observation that mattered for his later reasoning about animal distribution.

### Climate and health conditions
He described the region as **hot, damp, and fever-prone**, and like many European naturalists in the tropics he suffered recurring illness during the broader expedition. The swampy environments and mosquitoes made sustained inland work physically hard.

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## 3) Where he stayed: Dobo and the Aru trading hub
Wallace based himself around **Dobo** (still a principal town in Aru today), which in his day functioned as a seasonal, trade-focused settlement.

He portrays Dobo as a place that could swell with activity due to:
- **Malay and other Indonesian traders**
- **Chinese merchants**
- Local Papuan/Arunese communities
- Maritime trade in forest and marine products (notably including **trepang**/sea cucumber and other commodities moving through eastern Indonesian networks)

For Wallace, Dobo was crucial because it provided:
- Boats and crew for excursions
- Food and supplies
- A route for shipping specimens out
- Local knowledge about where desirable birds (especially birds-of-paradise) could be obtained

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## 4) How Wallace collected in Aru (methods and logistics)

### Team and local expertise
Wallace rarely worked alone. He relied heavily on:
- **Local hunters and guides** who knew the forest and bird habits
- His assistants (during parts of the Archipelago work, Wallace is known to have traveled with and relied on helpers such as Charles Allen)
- Trade networks that could procure specimens, information, and labor

This matters because many iconic “Wallace” specimens were the product of a **field system**: Wallace’s planning and documentation combined with local hunting skill and regional logistics.

### Collecting techniques
In Aru he used a mix of:
- **Shotgun collecting** for birds (the standard method at the time)
- Purchasing or commissioning specimens from local hunters
- **Insect collecting** (nets, traps, beating vegetation, searching dead wood)
- Skinning and preserving specimens in difficult tropical conditions (constant battles with moisture, decay, and insect damage)

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## 5) The headline achievement: birds-of-paradise
Aru is inseparable from Wallace’s most famous bird-of-paradise episode(s). In *The Malay Archipelago* he gives a dramatic account of finally obtaining a spectacular adult male bird-of-paradise—an event he describes with intense excitement and relief after effort, waiting, and reliance on local leads.

### Why this mattered
1. **Scientific value:** Birds-of-paradise were central to European debates about:
   - Biogeography (why such birds were confined to the New Guinea region)
   - Sexual selection and the evolution of extravagant ornament (a debate that would later become strongly associated with Darwin, but Wallace’s specimens and observations were part of the broader evidentiary base)

2. **Commercial value:** These skins were highly prized. For a collector-naturalist funding himself, a successful birds-of-paradise harvest could materially support months of work elsewhere.

### What species?
Aru is associated particularly with the **Greater Bird-of-paradise** (*Paradisaea apoda*) and other Papuan-affiliated birds. Wallace’s own narrative focuses on the thrill of acquiring full adult-plumage males—because incomplete plumage, damage, or poor preparation reduced both scientific usefulness and sale value.

(Exact species lists vary by source and by what is counted as “from Aru proper” versus traded through Aru, but Wallace treated Aru as one of his key birds-of-paradise collecting locations.)

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## 6) Other animals he collected and emphasized
Aru was not only about birds-of-paradise. Wallace used Aru to underline the **Australasian character** of the fauna.

### Marsupials and “Australian-type” animals
One of Wallace’s recurring points: on Aru (and nearby New Guinea-associated regions) you encounter animals that are typical of Australia/New Guinea, such as **marsupials** (e.g., cuscuses and related forms), in contrast to the primates and many other mammals characteristic of the Asian side of the archipelago.

### Parrots and other birds
He collected and discussed various striking birds typical of the New Guinea region, including parrots and other forest species that reinforced his sense that Aru belonged zoologically with New Guinea rather than with western islands.

### Insects
Although the public memory of Aru focuses on birds-of-paradise, Wallace was always collecting insects—especially beetles and butterflies—because they were:
- Abundant
- Diverse
- Easy to transport compared to large vertebrates
- Extremely informative for patterns of geographic variation

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## 7) People, culture, and the frontier economy (as Wallace saw it)
Wallace’s Aru chapters are also a snapshot of a 19th-century **commercial frontier**:
- He describes a multi-ethnic maritime trade world
- He notes sharp differences between coastal/trading settlements and inland communities
- He depicts the dependence of visiting traders (and collectors like himself) on local labor and expertise

His descriptions reflect the biases and language of a Victorian traveler, but they also provide a valuable historical record of Aru as a node in eastern Indonesian trade networks.

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## 8) Aru’s big scientific significance for Wallace: biogeography and “the Australian side”
### Aru as evidence of shallow-sea connections
Wallace repeatedly reasoned from geography to biology: **shallow seas** imply that land may have been connected during periods of lower sea level, allowing animals to spread; **deep channels** imply long isolation.

Aru is on the **Sahul shelf**, the same shallow continental shelf associated with New Guinea and Australia. Wallace used observations like “Aru looks and feels like an extension of New Guinea” plus the **Australasian fauna** to argue that Aru’s animals made sense if Aru was (in effect) part of the New Guinea/Australia biological region.

### Relation to the broader “Wallace Line” idea
Wallace’s later-famous boundary—often summarized as the split between Asian and Australasian faunas—was informed by exactly these kinds of comparisons. Aru sits firmly on the **Australasian** side of that divide, and Wallace treated it as a strong example of how abruptly the animal world changes across certain parts of the archipelago.

So, while the “Wallace Line” is typically discussed with reference to places like Bali/Lombok and Borneo/Sulawesi, Aru mattered as a vivid confirmation: *go east enough, onto the Sahul-associated islands, and the entire cast of animals changes.*

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## 9) Practical outcomes: specimens, sales, and reputation
Wallace left Aru with:
- High-value bird skins and other vertebrates
- Large numbers of insects
- Field notes that later became some of the most memorable passages in *The Malay Archipelago*

These collections helped cement his reputation in Britain as a serious field naturalist and supplied material that fed into museum science and private collections.

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## 10) Where Wallace wrote about Aru (primary source)
Most of what we “know” in detail—daily conditions, travel logistics, collecting stories, and his reflections on animals and people—comes from:

- **Alfred Russel Wallace, *The Malay Archipelago* (1869)** — the key narrative source, with substantial discussion of Aru, its trade town (Dobo), and the bird-of-paradise collecting.

Scholars also cross-reference his correspondence and specimen records, but for a coherent account, *The Malay Archipelago* is the centerpiece.

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## If you want, I can tailor this to what you mean by “everything”
I can expand in any of these directions:
1) A **chronological reconstruction** (arrival → base at Dobo → excursions → departure)  
2) A **species-level list** of notable Aru specimens attributed to Wallace (as far as records allow)  
3) A **biogeography deep dive**: how Aru fits Sahul vs. Sunda and how Wallace argued from sea depth and geography  
4) A **trade/history view** of Dobo and Aru’s role in eastern Indonesian networks during the 1850s–1860s

Which of those do you want?
