Some of you might know that Douglas Adams had a soft spot for dodos. There's the 'Megadodo Publications' of the Hitchhikers's Guide books, and there's also a mention of them in his book Dirk Gently's Holistic Detective Agency. Many people today know about dodos, but only think of them as ugly, ungainly, extinct birds. Some people might have seen them comically and extremely inaccurately portrayed in the Ice Age animated movie. In truth, there's much more to dodos than that. I'd like to try and do my little bit of justice towards them, and also convey a sense of the tragedy of extinction, whether of dodos or of anything else.

First – for those folks who don't even know what a dodo is:

Dodos were large birds that were unable to fly, and that were known from one place in the world only – the island of Mauritius. This is a volcanic island, in the Indian Ocean, just inside the tropics, rather far from any other place except its two neighbour islands Reunion and Rodrigues – the three together are called the Mascarene Islands. The group lies a thousand kilometres east of Madagascar, and more than two thousand kilometres from the southern tip of India. Mauritius was covered in lush tropical forests, and the dodos lived in these forests. They were quite large birds, like fat turkeys, up to about 23 kg/50 lbs in bodyweight. Their plumage was grayish, their wings very short, and they only had a few curly feathers for a tail. Most impressively, the dodos had huge, long, curved beaks, extending forward from their naked, leathery faces.

Dodos are often seen as ridiculous, poorly adapted, helpless and stupid. In truth they were perfectly adapted for their environment as it was before people arrived. Indeed, excepting their extinction, they could be called very successful. The island of Mauritius had risen from the sea as a result of volcanic activity, probably about ten million years ago, and was never connected to any mainland region. The island became populated entirely by animals and plant seeds that could either get there by flying or drifting through the air, or by floating on the sea. Birds had an advantage because of their flight capability. Mauritius was colonized by a number of bird species, including doves and pigeons, parrots, white-eyes, rails, and some other kinds. Mauritius is further away from Asia than from Africa, but surprisingly most of its birds show strong affinities with Asian species. Over the millennia, however, the birds that had arrived there, changed and evolved separately from their ancestors, becoming entirely different species, unique to the island.

Among these bird species, the dodo stood out. It was by far the largest, and also, it was not clear just what kind of a bird it was! Initially some people thought it might be a kind of rail; there were also thoughts they might be relatives of ostriches, vultures, penguins and several other bird groups. Only later, with detailed analyses of the remains of dodos – since by then they were already extinct – it was determined that they were, in fact, giant pigeons! Recent genetic studies done from preserved material confirmed this.

Externally the dodo seems so different from pigeons, though, that it has been placed in its own subfamily of the pigeon family. It shares this subfamily with only one other species –the Rodrigues solitaire. Which is also now extinct. Here's a picture of it:

Its name came from its supposed habit of individuals keeping to themselves, whereas dodos apparently often went about in flocks or groups. What's very interesting is that the Rodrigues solitaire also couldn't fly! And yet, it was quite like the dodo in appearance ... only, taller and rather more slender in build, with a smaller bill and a swan-like black bump at the top of the base of the bill. But Rodrigues never was connected to Mauritius ... there are hundreds of kilometres of ocean between the two islands. So the question is this: how did one flightless species end up on Rodrigues and another on Mauritius? Did they first diverge from other pigeons for a while ... becoming larger, mainly, but still capable of flight ... and then separately become flightless on both the islands?

The Rodrigues solitaire had wings that were not flight-capable, but still functional! The way it functioned was like this: there had evolved two thick bony knobs on the wrists, said to be the size of old-fashioned 'musket balls'. With these knobs, the males bashed each other when fighting for females. For this reason, its wings were still considerably bigger than the dodo's.

Maybe the ancestor of the dodo arrived first on either Mauritius or Rodrigues, evolved there for a while to the point of being quite big but still able to fly, and then some flew to the other island, subsequent to which both groups became flightless, evolving into two quite different species. But we don't know how it happened, or which island the 'dodo ancestor' came to first.

And there's still the question as to what group of pigeons the dodo and the solitaire evolved from. The closest in terms of bill shape, is the strange tooth-billed pigeon which only occurs on the islands of Samoa in the Pacific Ocean, many thousands of miles away! But other studies suggest that the dodo and solitaire come from a group of Oriental fruit doves. It has been said that the lovely Nicobar Pigeon, of the islands of Southeast Asia, might be their closest living relative.

This might give you an idea how successful dodos actually were. First of all – they (well, their ancestors) reached a small island in a vast area of ocean, after flying literally thousands of miles. Then, they managed to find the right kind of food, from trees quite different to the ones they knew back where they came from. Enough of them reached the island to enable them to start breeding. They managed to survive 'genetic bottlenecks' – a problem that occurs in very small populations because there's not enough healthy genetic diversity in such a small group, making them vulnerable to diseases and maladaptive mutations. No – they overcame that, and thrived, and their evolution kicked into fifth gear. They evolved faster and further than anything else. They changed enormously in appearance from the small, far-flying fruit doves they used to be. (Their bodyweight increased by a factor of almost a hundred.) And, it was all adaptive! In the forests of Mauritius the dodo became the largest bird species. The only other large animals on the island were giant tortoises. The dodo therefore had no natural enemies. It had no need to fly, and it nested on the ground in large colonies. It was apparently an eater of fruit and seeds that fell from the trees, picking them off the ground and crushing them in its huge bill – or swallowing them whole. So it adapted in lifestyle, moving from feeding in trees, to feeding on the ground.

The same kind of process led to the evolution of the Rodrigues solitaire. This is also a proof of the robustness and evolutionary potential of their fruit-dove ancestors. Little is known of the solitaire's lifestyle, though – apart from its living alone and the males bashing each other, that is. Its island was apparently a much more barren, open place than Mauritius was. It might have had a more varied diet, including perhaps animal and plant foods. The island being much smaller and less lush than Mauritius, there probably were never great numbers of solitaires.

I here want to note something. For a long time there was the belief that a third dodo species existed, called the white dodo, and that it lived on the third Mascarene Island, Reunion. Recently it was established that this was a mis-identification. The large, white, flightless, curved-beaked birds seen on Reunion, seem to have been ibises! Bones have been found of a large, possibly (or almost) flightless relative of the sacred ibis of Africa and Madagascar. These ibises are white, and the old sailors who visited the islands were not highly trained and observant naturalists. In addition, there are some illustrations of albino Mauritian dodos, that somehow got attributed to the white Reunion species, and so one can see how the idea of a 'white dodo' could have come about.

So today we know only of the two species, the dodo, and the solitaire, and they together constitute the dodo subfamily of the pigeon-and-dove family.

In losing them, therefore, we haven't just lost two species, we have lost an entire group of birds, of which they were the sole representatives. There are no birds left that are anything like them. They were by far the largest pigeons or doves ever known to exist. The dodo could, like I said, reach 50 lbs/23 kg in weight. The largest remaining pigeon is the spectacular crowned pigeon of New Guinea ... which is huge for a pigeon, but still a 'mere' 1.5 kg/3 lbs in weight. The dodos and solitaires were in fact some of the largest island-living birds ever known. (They are only exceeded by the equally-extinct moas and adzebills of New Zealand, the elephant-birds of Madagascar and the Sylviornithids – huge pheasant-like birds –of New Caledonia. But all those islands are much larger than Mauritius is.) The utter uniqueness of the dodo emphasizes the factors of diversity and localness: isolated 'places' on Earth develop differently from each other; very tiny differences in things like climate, landscape and the specifics of the food web, can lead to radically different evolutionary pathways. Most people in the world still don't understand this, and don't understand how 'small' places all over the world are still the homes to creatures found there and only there, nowhere else.

How did the dodo die out? It was only 'discovered' to science in 1598, and in 1680 none more could be found. It seems to have originally been quite abundant on the island. The Dutch sailors used the islands as a stage on their way to and from India, and stocked up on meat whenever they stopped there, killing dodos (and other things like giant tortoises too) and salting their meat. They also brought dogs, cats, rats, pigs, and crab-eating macaques (an Asian monkey species) to the island, all of which made ready meals of dodo eggs and chicks.

And now comes the important thing to realize. Dodos were adapted to conditions on the island as it was before people came. When conditions rapidly changed they were not capable to adjust rapidly enough, because evolution happens over thousands of years, not over mere decades. This is not to say that dodos are 'losers' for not being able to adapt, because even we humans are slow to adapt and we as well might one day find ourselves facing changes that are taking place too rapidly for us to adapt to. It's a lesson, people!

So: dodos became big because the lush forests had enough food for them to become big on. There was a 'niche' for a large herbivore on the island, and the bird filled it. It became incapable of flight firstly because it became too big and heavy to fly – but also, it was not necessary for it to fly. It could live, feed and breed on the ground. There was no problem with that, since there were no ground-living predators that could threaten itself or its chicks or its eggs. Also, it became a slow breeder – as did the solitaire on Rodrigues. The reason being, on a smallish island, if you breed too fast – and there aren't predators to keep your numbers down – you quickly grow too abundant for the resources of the island to sustain. So – you breed more infrequently. (Douglas Adams also speaks about this infrequent-breeding factor in his book Last Chance to See about the weird flightless parrot, the Kakapo of New Zealand).

This strategy worked for the Dodo for thousands of years ... but when things changed, rapidly, it didn't work any more. There was no way the Dodos could cope with large numbers of them being caught and eaten by Dutch sailors, or large numbers of their eggs and chicks being eaten by all sorts of new immigrant animals.

The people who wiped out the Dodo and the Solitaire (not even to mention many other species that were unique to Mauritius, Reunion and Rodrigues) did not know what they were doing. They did not understand the uniqueness of the wildlife they were destroying and they didn't even understand that species could go extinct. Only when much later, in the latter half of the 19th Century, Charles Darwin brought the phenomenon of evolution to public attention, could people start understanding (except for the ones who even up till today stubbornly refuse to admit that evolution happens). By understanding the process of evolution, we can understand that animals and plants arriving on distant, isolated islands, could over time, by evolving in isolation, become totally unique – very different from anything else in the world – and the longer they can evolve, the weirder and more unique they can become. But also, they – like all species – are vulnerable to extinction. The smaller an island is, the more vulnerable the species living on it are. But ultimately, even the entire planet Earth, is nothing more than an island floating in space. We're at the point where everything – including ourselves – is in danger.

Today, the knowledge and info is there so we should by now know about species that are unique – wherever in the world they may be – and about the processes threatening them. And we should do what we can to preserve them! Because – every species that lives on this planet is part of the richness of life. We are merely one species among millions, and we, too, are part of that richness. We lose knowledge with every species that is lost. Because the dodo exists no more, there's much that we cannot learn and know any more. The bits and pieces that are left are not enough for us to really get a sense of what these birds were all about.

If they still lived, first of all, it would be a thrill to see them. Mauritius today is a popular tourist destination. The opportunity to see flocks of living dodos would have attracted even more visitors and certainly would have delighted many children – and adults! Living dodos could also have effectively carried the message of unique island life to the public. But now the dodos are no more – the closest thing to them remaining on Mauritius is the large and lovely pink pigeon ... itself also almost wiped out. It's a handsome bird but far less weird and impressive than a dodo.

If dodos were still alive, we could study them in numerous ways. Most certainly if they still lived, a detailed study of their behaviour would have proved that they were nothing like the buffoonish and inept image that many people have of them. We could have held them up as an example of efficient physical and behavioural adaptation – ongoing and ever-changing – to life on an isolated island. There's so much we don't know. How long have they been living and evolving on Mauritius? How rapidly did they become as big as they were? When did they lose the ability to fly?

We could work at the answer to these questions if we could study the genes of living birds. The mouldy museum-pieces we have left, yield nothing like the wealth of genetic info we would have found in a healthy, abundant and thriving population.

We could ask: what kinds of foods did the dodos eat? We don't even know that. There's for instance a tree on Mauritius, sometimes called a 'dodo tree' that produces a very hard seed, that won't germinate unless – apparently – it travels first through the gut of a large bird. For many centuries apparently no seeds have germinated and the trees were becoming rare – until today it seems seeds can be made to germinate if they pass through the guts of turkeys first!

But actually we still don't know if dodos really ate these seeds. It might have been some of the giant tortoises who ate them. The tortoises are also extinct now. It's a whole ecosystem that has vanished! We cannot study it any more as it used to be. It's gone! We cannot any more see how for instance the plants and other living things of Mauritius were affected –and in turn affected – the dodos. We can't study the way they co-evolved. We can't study the way the different species used the resources of the island together in a way that sustained them all in their interrelationships. The whole system, as it used to be, is gone – what's left is just a shadow of what once was.

And think of this: ANY kind of knowledge we could have learnt could have helped us understand ourselves and our world better. Learning about how species evolve in isolation on an island ... learning how they form stable ecologies ... could tell us a lot of things, things that we might soon need to know in a global context. Because like I said, we, too, are part of the richness of Nature and we are part of its processes. When we understand the evolution of other species we will understand our own evolution better as well – because we are still evolving! The more we understand of evolution, the more we understand about the potential of everything – ourselves included – to adapt and change, to become diverse – and more interesting! To make the most of new opportunities, for being creative, and growing. When we understand the vulnerability of island ecologies – or any ecosystem on Earth – we understand our own vulnerability as well – and how to minimize it. When we see how island ecosystems – or any ecosystems – function over thousands and millions of years, and how the various species sustainably use the resources, we learn about using the resources of our own planet better. There are millions or even billions of such things we can learn from studying other living species, and their living communities, on this planet.

In the end it's more than just knowledge we can use for practical purposes ... for getting richer or more successful or whatever. It's knowledge that, in itself, enriches us. The Life of this Planet is part of the creative processes of the Universe. I would say that Life is the most important and interesting thing going on in the Universe right now. By the laws of Nature, Life has come into existence here on Earth and diversified over thousands of millions of years. How it did that is fascinating and demands a study that goes into every little corner of our planet, and that stretches back to look at how things changed over the course of millions and billions of years. It is an utterly awe-inspiring thing to study and contemplate. And we are part of it! No matter how 'artificial' we make our world and our lifestyles, we came from Nature and in essentially the same way as every other living thing came from Nature. No matter what we do we cannot break with that! We cannot just establish a new 'system' of our own making, to wipe the slate clean, to wipe away everything else that went on before. It is to declare war on our own heritage. We can try, but we never will succeed ... and the more we 'succeed', indeed the more we will simply alienate ourselves from our world ... and eventually we will alienate each other and our own inner souls as well.

It is infinitely better if we all start realizing being part of the natural World, the living planet Earth; and if we all start respecting our fellow living beings. And each other, too! There's no limit to love and respect. The more things we love and respect, the more we become augmented by it, the more we appreciate and cherish our own lives, each other, and everything. In losing the Dodo, the Solitaire, and many other little bits of the living world, we are losing little bits of our own souls. We are losing knowledge, we are losing 'links' with our own reality, we are losing an understanding of our own very fragile existence here on a planet that itself is an island adrift in space... filled with utterly unique and irreplaceably precious life. Us included.

We need to think about how much greater the Natural World is than our human-created society. Wild Nature has owned this planet for thousands of billions of years before we came along. Until a few hundred years ago – a vanishingly small period of time in the bigger scheme of things –the landscape of the majority of the continental landmasses was untouched by human development, and animals and plants ranged free all over it. Over the past few hundred years we have wrought radical changes, and much of the planet now looks quite different with our cities, farms, roads and so on, and the majority of animals can't roam where they wish any longer. Just about all large mammals, apart from the ones we breed on our farms, are on the decline. Species are going extinct, ecosystems are breaking down. There's the troubling possibility that the global ecology is no longer functioning as it has –having up till now, maintained stability and very high biodiversity for millions of years, even over crises such as the asteroid that wiped out the dinosaurs, and the much more recent ice ages. We are now messing it up, being generally ignorant of how much damage we are causing, generally lacking an understanding of the complexity of the global ecology, generally lacking knowledge of the vastness of time over which this global ecology has come into being, only thinking of 'the human world' and ignoring everything else – which is so vast and complex in terms of time and space and diversity that it goes beyond our comprehension. But ... Nature is still in charge. We humans are just a tiny bit of the Universe. The laws and process of Nature created the stars and the galaxies, and those same laws and processes created life here – and elsewhere, I'm quite certain of that. And if we can't appreciate it – we ourselves might soon wipe ourselves out. And evolution will then get back on track. There are millions ... perhaps more than a billion ... years left before the sun becomes unstable; certainly evolution could again produce a diversity of creatures even greater than what existed before. And even on Mauritius! Give the pink pigeon – or any of the other pigeons and doves living there or on any other island – another ten million years or so ... and they, too, would evolve into new things possibly as weird as the dodo! But unless we wise up, we might not still be around then to see them.

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