For many, the Galápagos Islands are the prime example of the creative power of natural selection. After all, their wildlife inspired a young Charles Darwin to develop his theory of evolution. But on another archipelago, 5000 miles to the west, evolution has put on an even greater show.
Hawaii gives a new meaning to the word "remote". Marooned in the central Pacific, this chain of eight main islands is the only significantly-sized land for thousands of miles. If you sailed due west of Honolulu, the next thing you'd hit would be Taiwan: almost 6000 miles away.
Despite its isolation, Hawaii is anything but lonely. The archipelago boasts thousands of species of animals and plants. Most are found nowhere else on Earth, and many are startlingly different to their more familiar relatives. What was it about these islands that allowed evolution to become so creative?
When Charles Darwin visited the Galápagos Islands off the coast of South America, he collected specimens of the local finches. At the time he thought little of it.
Years later, it emerged that the finches on the Galápagos were wildly diverse. There were about 14 species, each with a different shaped beak that allowed the bird to live a lifestyle unlike any other such bird. One behaved like a woodpecker.
The Galápagos finches are a classic example of evolution in action
The birds were a classic case of evolution in action. "Normal" finches had come to the islands from the mainland and, finding them empty, had tried out all sorts of different lifestyles – eventually evolving into separate species. Biologists call this "adaptive radiation".
In some versions of this story, the finches were one of the key discoveries that prompted Darwin to develop his theory of evolution. In fact Darwin hardly wrote anything about the Galápagos finches, and drew most of his examples from elsewhere. It was only after he had worked out his ideas that he realised the finches' importance.
Regardless, the Galápagos finches are a classic example of evolution in action, and of adaptive radiation in particular. But when adaptive radiation took place in Hawaii it was even more prolific.
The first birds to reach the islands probably arrived around 8 million years ago from east Asia.
They range spectacularly in colour, from bright shades of red to muted golds and greens
We'll never know exactly how these colonists made the epic journey. But once they had done so, they took to their new home like, well, like birds to empty islands.
Over the eons these founders evolved into at least 140 species of bird.
Hawaii's equivalent of Darwin's finches is the Hawaiian honeycreepers, which branched into at least 56 species from just one or two. They outstrip the finches in both number and variety.
They range spectacularly in colour, from bright shades of red to muted golds and greens.
Their beaks, too, have changed shape, reflecting the different lifestyles each bird has adapted to. The beaks of the honeycreepers range from short to long; from stubby and delicate; and from straight to curved, and ingenious combinations of the two.
The scarlet-hued 'i'iwi has a thin, drooping break which it uses to reach the nectar of flowers.
Meanwhile the multicoloured 'akiapōlā'au has a beak that's often compared to a Swiss Army Knife. It has a straight and stout lower mandible and a slender, arched upper one. This makes it a perfect tool for excavating insects from beneath the bark of trees.
The giant Hawaiian darner grows to a wingspan of over 15cm
The insects have been even more prolific. Hawaii has more than 5000 endemic species, many of which have evolved spectacular adaptations to island life.
Some swelled to gigantic sizes. One dragonfly, the giant Hawaiian darner (Anax strenuus), grows to a wingspan of over 15cm.
Flies of the family Drosophilidae (which contains fruit flies) split into a dizzying number of species. More than a thousand are endemic to Hawaii: around a quarter of the world's total, despite occupying less than 0.01% of its land area.
But the award for the most striking evolutionary shift goes to a different Hawaiian insect.
We tend to think of caterpillars as puttering around slowly nibbling on leaves. Not on Hawaii. The caterpillars of some species of Eupithecia pug moth have become carnivores.
You just cannot beat the evolutionary leap of a plant-eating caterpillar becoming a predator
They actively hunt their prey, perching motionless on leaves before snatching the passing flies out of the air. They even have raptorial claws for the purpose.
"In my mind, the case of Eupithecia is the most amazing adaptation that took place on Hawaii," says Dennis LaPointe of the US Geological Survey's Pacific Island Ecosystems Research Center. "You just cannot beat the evolutionary leap of a plant-eating caterpillar becoming a predator."
Species like these have acquired eye-catching new attributes. But Hawaii's evolutionary history illustrates something important about evolution: what you lose can be just as important as what you gain.
The first organisms to reach Hawaii had all evolved to evade land predators. They arrived to find virtually none.
Although Hawaii is teeming with bird and insect life, it has very few large predators. There are no native reptiles, and only one small native land mammal, the Hawaiian hoary bat.
Large flightless ducks called moa-nalo were once the main herbivores on the islands
So over millions of years, natural selection whittled away their defences.
Hundreds of species lost the power of flight. On Hawaii you can find flightless moths, flightless wasps, and even flightless flies.
Birds also took to the ground. Large flightless ducks called moa-nalo were once the main herbivores on the islands.
Hawaii's plants also transformed to suit the lack of grazing animals.
Hawaiian holly is spineless and Hawaiian mint is tasteless. Humans like the flavour of mint plants found elsewhere, but it is actually a defence mechanism.
What's more, Hawaiian nettles don't sting.
However, the lack of grazing animals wasn't all good news for plants.
Outside Hawaii, beggarticks rely on land mammals to disperse their seeds. The fruits of the flowers are accordingly barbed to catch a ride on the hides of passing beasts.
The Hawaiian versions predictably lost their barbs. Instead they developed flattened, winged or twisted fruits. These could be picked up by another suitable scatterer: the wind.
But why here? What is it about Hawaii that led to such rampant biological change?
There's no single answer. But one reason for the extraordinary abundance of life is that it is so hard for anything to get there.
Most of the animal colonists took a more dangerous route
Genetic studies suggest that the ancestors of most of Hawaii's native species came from east Asia and North America. Their journey to the islands may have included the odd stop-off at a coral atoll or other small island, but even so, getting to Hawaii meant crossing hundreds or thousands of miles of open ocean.
For the plants, the journey across the Pacific must have been relatively simple. They merely had to hitch a ride on a piece of oceanic debris, and bide their time.
But most of the animal colonists took a more dangerous route. They were blown on the wind.
Most of the founding birds and insects probably hitched a ride on mild mid-altitude air currents. However, some may have taken a trip in the jet stream, which is much higher – so temperatures fall below 0 °C.
Many species didn't make it at all
Some spiders are also thought to have taken an aerial route to the islands by gliding on their own silk. Spiders often journey like this – it's called ballooning – but the trip to Hawaii must have been a hairy one.
And spare a thought for the American ancestors of the Hawaiian Hoary bat. They must have got caught in a hell of a storm.
Many species didn't make it at all. As well as their complete lack of reptiles and extreme paucity of mammals, the islands have no native ants, termites, cockroaches, mantids or scorpions.
What's more, although birds did reach Hawaii, they did so in such small numbers that only a handful of avian families are represented.
This exclusivity was a boon to those species that did reach the islands.
With fewer competitors, these lucky few were able to exploit environmental niches that would otherwise have been occupied by other species.
For example, woodpeckers and hummingbirds never made it to Hawaii, so new species of honeycreeper evolved to fill their niches – the 'i'iwi and 'Akiapola'au, respectively.
Similarly, the prayer-like hunting stance of the Eupithecia caterpillars is eerily reminiscent of the absent mantids.
Another reason for Hawaii's evolutionary vigour can be traced to the birth of the islands themselves.
Each one was formed by underwater volcanic eruptions, which built them up from the sea floor over hundreds of thousands of years. The Big Island, which is unsurprisingly the largest, rises more than 4km above the waves.
Perhaps the most extreme conditions are found on the peaks of Hawaii's volcanoes
As a result, despite its tropical location, Hawaii has a surprisingly diverse climate. Conditions range from balmy rainforest at sea level to arid alpine scrub and even deserts near the highest peaks.
This climatic diversity imposed another level of isolation on Hawaii's inhabitants. Two species living on the slopes of a volcano might be separated by just a few hundred metres, but still be living in significantly different climates.
For example, a warmth- and moisture-loving tree might thrive in the wet lowlands, whereas a species adapted to colder, more barren conditions might dominate further upslope. These abundant climatic niches carved out by Hawaii's volcanoes boosted its evolutionary flourishing still further.
Perhaps the most extreme conditions are found on the peaks of Hawaii's volcanoes.
The Big Island is the chain's only volcanically active island. It contains both the world's largest land-based volcano, Mauna Loa, and its tallest, Mauna Kea.
Mauna Kea is arguably the tallest mountain on Earth. It rises at least 9966m through the water, depending what you think is the bottom, before then ascending a further 4200m above sea level. That makes it is around 14,000m tall, dwarfing Everest's puny 8848m.
Mauna Loa isn't quite so high, topping out at 4169m. Still, both are high enough that it regularly snows on their summits, even though they occupy the same latitude as the southern Sahara.
Even here, though, Hawaii's animals have managed to adapt.
The tops of these volcanoes look like the surface of the Moon. There are almost no plants. Nevertheless, two species of the seed bug genus Nysius have dramatically altered their diet to survive on the roof of Hawaii.
Most other insects die at such low temperatures
"Wekiu bugs" live exclusively on the summits of Mauna Kea (N. wekiuicola) and Maua Loa (N. a'a). They subsist on the carcasses of insects that blow up the volcanoes. No other species of Nysius does this.
But food alone isn't enough to survive at these altitudes. To endure the often freezing temperatures, the blood of Wekiu bugs contains a compound that acts like antifreeze, preventing the formation of ice crystals. Most other insects die at such low temperatures, conveniently enough for the Wekiu bugs.
These Hawaiian species brilliantly demonstrate life's ability to adapt to extreme situations. But for many, the arrival of humans has been too extreme.
The first human settlers landed between 300 and 600AD. They were probably migrants from the Marquesas islands, 2400 miles to the south, who knew their way round a canoe.
The Moa-nalo, after thriving for some 3 million years, were extinct by 1000AD
These Polynesian colonists introduced pigs, dogs, rats and cats to Hawaii. Combined with deforestation, this spelled the beginning of the end for many of the archipelago's native creatures, which were completely unprepared for the voracious immigrants.
Birds were amongst the worst hit. The Moa-nalo, after thriving for some 3 million years, were extinct by 1000AD (echoing the demise of the Dodo on the island of Mauritius, and the Moas of New Zealand). We only know about them from their buried bones.
So too was the nēnē-nui, a type of goose.
Geograpsus severnsi, a large, bird-eating crab only recently identified by shell fragments, died out at around the same time.
When Captain Cook landed in 1778, ushering in the colonial era, the decline of Hawaii's native fauna accelerated. Today, many of its endemic inhabitants exist on a knife-edge.
Only 18 honeycreeper species are thought to be left, and some of those have not been seen in the wild for years.
One of these, the elusive po'ouli, is the sole surviving member of one of Hawaii's most ancient lineages. It may already have perished.
Frantic conservation efforts are underway to preserve what remains of the Pacific's evolutionary hotspots. The Galápagos Islands are rightfully receiving a large slice of this aid. But Hawaii deserves to share the spotlight.
Darwin never made it to Hawaii, and never saw its inhabitants. But judging by the love of "wondrous and diverse forms" that he described in On the Origin of Species, we can safely assume that he would have adored them.