Woodpecker finch (Camarhynchus pallidus) stick probing

Picture this: a recent Californian high school graduate, 17 years old, goes on an extended cruise to some exotic volcanic islands off the coast of Ecudaor. There, he drinks in the landscape and marvels at the strange and often unique forms of life all around him. It’s a true paradise, a life-changing experience.

And then he starts shooting the birds.

By the time he’s done, by his own count he and his accomplices have amassed over 8,000 dead birds (8,691 to be exact). Among them are the small feathery bodies of one of the few tool-using animals known at the time, plus innumerable eggs and nests to complete the haul. All of which the boy packs in his luggage and heads back north to California, considering it a year well spent.

The archipelago from which he’s gathered these dead treasures is probably familiar to you—it’s the Galápagos islands. It’s where Charles Darwin famously collected important pieces of the evolutionary puzzle that he would turn into his theory of natural selection. It’s also not somewhere you’d expect to find wholesale slaughter of the native wildlife. Unless the killer happened to be attached to a respected scientific society.

This is the tale of the woodpecker finch, and Edward Winslow Gifford, the boy who first alerted the world to their tool use and helped capture their corpses for science.

The Academy

As you might have guessed, this particular sea voyage happened well before modern conservation standards were introduced. Gifford’s boat, the 87-ton schooner ‘Academy’, left San Francisco on 28 June, 1905, and returned almost a year and a half later in November, 1906. The learned society behind the Galápagos Expedition was the California Academy of Sciences, which had developed over the previous half century into a major natural history museum and research institution.

In this post we’ll spend a little less time than usual on the animal behaviour itself—although we’ll cover that too—and a little more on the people who encountered and reported on woodpecker finch (Camarhynchus pallidus) tool use at the start of the 20th century. Some time in the future we’ll return for a deeper dive into the birds themselves, including recent work on their cognition and adaptive specialisations, but today context is key. Hence, Edward Gifford.

In this picture of the Academy crew shortly before they started out (from Matthew James’ book Collecting Evolution), Gifford stands third from the right, arms folded, young and confident:

Gifford’s title on the Galápagos Expedition was assistant ornithologist, or bird scientist. He was joined by a more experienced birdman, Joseph S. Hunter—standing tall behind the seated man in the photo—as well as a botanist, geologist and conchologist (the same person), entomologist, two herpetologists, and a ship’s mate, navigator and cook. These nine men were overseen by the expedition chief, Rollo Howard Beck (that’s him just to the left of centre, with his hand in his pocket). In his mid-30s at the time, Beck was himself an accomplished sailor and ornithologist who, like Gifford, combined a smattering of formal education with a deep curiosity about the natural world.

The Expedition visited and collected specimens from more than 20 of the Galápagos islands, with the most time spent on the largest, Isabela (at the time known to the US scientists as Albermarle). Isabela is a conglomeration of six shield volcanoes, and the island remains quite volcanically active. Like the other, smaller islands nearby, Isabela has its own differentiated animals and plants, including the giant reptiles that give the group its name: galápago is an earlier Spanish term for tortoise.

A small twig

So, what about those woodpecker finches? They are one of more than a dozen species of finches endemic to the islands, collectively sometimes referred to as ‘Darwin’s finches’ after the naturalist used evolutionary differences in their forms to reinforce his idea of natural selection. These finches are divided into four genera—a fifth is found on Cocos Island to the northeast—with the woodpecker finch currently considered a member of the Camarhynchus or ‘arch bill’ genus.

Darwin didn’t actually use the Galápagos finches as a specific example in his original 1859 edition of the Origin of Species. However, several times in that book he spoke more generally of the land birds of the islands, and of how their subtle differences implied successive colonisation and adaptation to new environments. He also remarked on how the finch beak sizes varied at fine scales from very large down to tiny, and his earlier 1845 account of his journey on the HMS Beagle highlighted four of them with an image drawn by John Gould:

Commenting on the beaks, Darwin wrote in his 1845 Beagle book that:

Seeing this gradation and diversity of structure in one small, intimately related group of birds, one might really fancy that from an original paucity of birds in this archipelago, one species had been taken and modified for different ends.

Research since Darwin’s day has shown that the beaks of the Galápagos finches can indeed be neatly paired with the foraging behaviour that each species has adopted. Evolution, it appears, has partitioned the birds into dining clubs that make the most of the full range of resources available, although each bird also shows some behavioural flexibility rather than a strict dietary regime. For example, the sharp beak of the vampire ground finch Geospiza septentrionalis allows it to sometimes—you guessed it—peck open wounds in other birds to drink their blood. Meanwhile the large ground finch Geospiza magnirostris (top left in the image above) uses its strong beak to crack open nuts and seeds. And the small tree finch Camarhynchus parvulus, now placed in the same genus as the woodpecker finch and shown bottom left in Gould’s image, has a beak that works for picking at small insects amid tree bark.

It’s not a big stretch to go from picking at insects on the tree surface to searching for larvae buried inside the same trees. This is the niche claimed by the woodpecker finch, with a little help from any cactus spines or thin twigs in the vicinity:

Here’s Gifford with the first published report of this behaviour in Geospiza pallida, now Camarhynchus pallidus, in the California Academy journal of July 1919:

In the arid region 10 miles west of Villamil, Albemarle [Isabela], I one day watched a bird feeding in a leafless, dead tree. It was apparently searching for insects, for it inspected every hole carefully. Finally it found one too deep for its bill. It then flew to a neighboring tree and broke off a small twig, about half an inch in length. Returning to the hole, the bird inserted the little stick as a probe, holding it lengthwise in its bill. It proceeded to examine other holes by the same method. Mr. Beck and Mr. King [assitant herpetologist] said they had noted similar instances elsewhere.

Surprisingly, the daily field notes Gifford took during the Expedition don’t mention any observation that match this description. It's not that he was an unobservant scientist either, as his field notes are in general comprehensive, fastidious and detailed. His youth and lack of formal training were not impediments to his skill in recording the natural environment.

Digging further, we find what may be an odd coincidence: Gifford’s ornithologist colleague Joseph Hunter had inscribed a very similar report in his own field notebooks on 4 January 1906, when the team was on James Island (now Santiago):

King reports a very interesting antic on the part of a pallida. It was pecking woodpecker like at a dead branch an inch and a half in diameter, and broke through to a borer hole. It tried to reach in to the end of the hole with its beak but could not reach the bottom. It then flew to a twig near, broke off a short one an inch or so long, took it in its bill so that the end pointed away from its beak in front and then went back to the hole and ran the stick in to feel if there was any grub in there. In this particular case there was none and the stick was dropped. Beck reports having seen this same performance gone through 2 years ago.

Here’s a modern video of the behaviour, which you’ll see is the same as that described by the Expedition team. The finch rapidly searches, attempts to use its beak to reach prey, makes a tool and uses it to investigate several holes. Plus, as a bonus, from around 35 seconds into the film you can see a giant tortoise hanging out in the background:

Who shot first?

Gifford’s publication and Hunter’s notebook tell essentially the same story, so who saw what when? It’s not that important for understanding the bird’s behaviour, but it does have some bearing on who should get any available credit for the work, and tells us on which island the behaviour was first seen. Neither Hunter nor Gifford seems that excited by the discovery either, and Expedition leader Beck’s notes from the time show that he didn’t think it worth writing them down himself. Here were animals making and using tools in the wild, 60 years before Jane Goodall stepped into the forest with the Gombe chimpanzees, and the finding barely raised a ripple.

In fact, the only mention of woodpecker finch tool use that I found in Gifford’s field notes—from the entire 1905-1906 Expedition—comes in a short passage written on 25 April 1906, as the team anchored in the south of Isabela:

I observed a bird with a straw lengthwise in its beak, poking it in to holes in a rotten tree in search of insects. Beck and King have observed similar instances other places.

Gifford then lists 7 woodpecker finches and 31 finches of other species that he and his team killed and collected that same day. It’s not reported whether the tool-user was among them. Here’s the relevant section from his notebook:

While it seems clear that Gifford did see tool use in action, his published account may owe more to Hunter’s recollections—attributed to the assistant herpetologist Ernest King—than his own observation a few months later. And both field notebooks point out that Rollo Beck had seen the same behaviour on a previous trip to the Galápagos a few years earlier.

Beck had by that stage made three voyages to the Galápagos. His first, in 1897, was financed by Walter (later Lord) Rothschild, who was using his family’s wealth to build a private zoology museum in Britain. Beck only joined that mission after the original ship’s sailing master and two of the hired collectors died of yellow fever shortly before it began, but he was successful nonetheless. Especially if success is measured by getting a live giant tortoise for Lord Rothschild to examine, or maybe to ride in his garden at Tring (now part of London’s Natural History Museum):

That really is Walter Rothschild, a grown and wealthy man, on that tortoise. But I digress.

If Beck saw finch tool use on his earlier travels then it didn’t make the publications that followed, many in Rothschild’s own journal Novitates Zoologicae. For example, in a 1902 paper updating the Galapagos findings, Beck is quoted as saying that these finches ‘feed more like a woodpecker than like other Geospizae. They were seen to peck open stems of cactus, apparently in search of larvae, and prying and picking under bark and in cracks in search of food’. If there was ever a time to mention the extraordinary fact of tool-assisted hunting, this would have been it. The sequence of sightings among these naturalists therefore appears to be (i) Rollo Beck, who mentioned it only to other crew, (ii) Ernest King, who reported it to Joseph Hunter as noted in his field book, and (iii) Edward Gifford, who published a brief mention in a report years later, in 1919. Conspicuously absent is Charles Darwin, who seems to have neither collected this particular finch species nor seen its probing activities.

What happened next

Even decades later, by the time of the second world war, woodpecker finch tool use was still little-discussed. Certainly there was nothing like the sensational coverage that would be later heaped on chimpanzees for also making stick tools and putting them in holes to catch bugs. One of the few who were impressed was David Lack, an English schoolteacher with a keen interest in robins, who went to the Galápagos in 1938 with the support of the Royal Society and London Zoological Society to study the finches. He confirmed the tales of Gifford and co. in a 1940 presentation of his results to the British Ornithologists’ Club, further stressing that the finch’s behaviour ‘seems one of the few recorded instances of the use of tools in the animal kingdom, outside man’.

Despite initially thinking that the different beaks seen among the finches were derived from a bird’s need to identify members of its own species (an assertion he later abandoned), Lack went on to write a bestselling 1947 book on the Galápagos finches. He chose a title that cemented the link to the work of a century before: Darwin’s Finches. He also gave up schoolteaching and moved to Oxford University to become a professor of ornithology.

One of the reasons that the finches failed to capture the imagination may have been that their initial proponent, Edward Gifford, also turned to other pursuits. In 1920, a brief note highlighting Gifford’s publication containing his finch tool use anecdote states that, after returning from the Galápagos, he was ‘subsequently occupied with anthropological work [and] has been unable to complete his report’.

That’s an understatement. Gifford not only turned his attention to studying humans, he ended up becoming a Professor of Anthropology and Director of the Anthropology Museum at the University of California, Berkeley. He led ethnographic and archaeological projects in the western Pacific, and helped build up detailed knowledge of the lifeways of indigenous Californians. At the time of his death in 1959, he remained one of the very few people who had studied both tool-using humans and tool-using nonhuman animals, but it was the former that ultimately gained his attention.

Actually, we’re lucky even to have the information that came from the 1905-1906 Expedition. By a quirk of fate, the Galápagos Expedition was still collecting in April 1906. That meant that their specimens were safe from the catastrophic earthquake and fires that destroyed almost all the California Academy’s other collected material (along with much of San Francisco) on the morning of 18 April that year. When the Expedition returned, their Galápagos material was essentially the start of a new museum.

Here’s the Academy building after the fire, with part of its facade and the internal elevator shaft still standing, along with the external walls of the museum behind:

Today, the California Academy of Sciences has a splendid new home in San Francisco’s Golden Gate Park, itself re-opened in 2008 after damage from the large 1989 Loma Prieta earthquake. The latest buildings are supposedly built with the latest in earthquake and fire-resistant features. Only time will tell.

As I mentioned, we’ll return in a future post to the woodpecker finches, including studies that look at their tool-use as an adaptation to their unpredictable environment. But for now we’ll leave Gifford, Beck, Rothschild and the rest of the crew, with a reminder that no matter how many dead birds you collect, their behaviour dies with them. Field studies have come a long way since the Galápagos Expedition, and it was only once people took the time to sit and watch these birds, not to club or strike or shoot them, that we could recognise the true artistry of woodpecker finch tool use.

Further viewing

Want a little more? Here’s a woodpecker finch diligently probing with its tool. And getting rewarded.

Sources: Gifford, E.W. (1919) Field Notes on the Land Birds of the Galapagos Islands. Proceedings of the California Academy of Sciences. Fourth Series. Volume II, Part II, pg. 189-258. || Gifford, E.W. (1905-1906) Galapagos Expedition Journal. https://www.biodiversitylibrary.org/item/123647 || Gifford, E.W. (1913) The birds of the Galapagos Islands, with observations on the birds of Cocos and Clipperton Islands (Columbiformes to Pelecaniformes). Proceedings of the California Academy of Sciences. Fourth Series. Volume II, Part I, pg. 1-132. || W.S. (1920) Gifford’s ‘Field Notes on the Land Birds of the Galapagos Islands’. The Auk 37: 162-163. || Darwin, C. (1845) Journal of researches into the geology and natural history of the various countries visited by H.M.S. Beagle. 2nd edition. John Murray, London. || Tebbich, S. et al. (2004) Feeding Behavior of Four Arboreal Darwin's Finches: Adaptations to Spatial and Seasonal Variability. The Condor 96:95-105. || James, M. (2017) Collecting Evolution. Oxford, Oxford University Press. || Hunter, J.S. (1905-1906) Galapagos expedition journals (December 1905 to September 1906). https://www.biodiversitylibrary.org/item/123634 || Rothschild, W. & E. Hartert (1899) A review of the ornithology of the Galapagos Islands, with notes on the Webster-Harris expedition. Novitates Zoologicae 6:85-205. || Rothschild, W. & E. Hartert (1902) Further notes on the fauna of the Galapagos Islands. Novitates Zoologicae 9:373-418. || Lack, D. (1940) The Galapagos finches. Bulletin of the British Ornithologists’ Club 60:46-50. || Sulloway, F. (1982) Darwin and His Finches: The Evolution of a Legend. Journal of the History of Biology 15:1-53. || Leviton, A. et al. (2006) The California Academy of Sciences, Grove Karl Gilbert, and photographs of the 1906 earthquake, mostly from the archives of the Academy. Proceedings of the California Academy of Sciences 57:1-34.

Main image credit: Dusan Brinkhuizen || Second image credit: California Academy of Sciences; James (2017) || Third image credit: John Gould; Darwin (1845) || Fourth image credit: D. Parer & E. Parer-Cook || First video credit: Kjetil Voje || Fifth image credit: Mary Plage || Sixth image credit: Gifford (1905-1906) || Seventh image credit: Natural History Museum; https://www.nhm.ac.uk/discover/walter-rothschild-a-curious-life.html || Eighth image credit: Tierbild Okapia || Ninth image credit: Frank Marion Anderson; Leviton et al. (2006) || Final video credit: Lucy Haskell