Island Biogeography

Islands are dynamic wild laboratories. Picture a block of sea floor lifted from the abyss by tectonic action or a steaming pile of lava rising from the boiling water as the earth’s innards are expelled upward. Each of these could become a remote isolated island surrounded by salt water; barren and empty.

Now picture yourself returning in a hundred years and then a thousand years and then again in ten thousand years. What changes can you imagine? It is likely that the uplifted piece is now vegetated and full of insect and bird life. Even the stark lava island could be harboring sea birds and plants that grow in their droppings. There might be hardy creatures like lizards or turtles or even land birds. Now think about New Zealand, Hawaii, and the Galapagos Islands. This is not hypothetical – this series of events has happened over and over and over again. The following books speak to island life and evolution and things that might (nay, must) travel over our planet filling empty places and leaving places less suited – or making the necessary changes to survive.

Islands as a laboratory was the concept behind Wilson and Simberloff’s work in the Florida Keys. It was actually Wilson and MacArthur who coined the term “island biogeography” which was tested by assessing reestablishment of life on small mangrove keys; a project of the early 1960s which involved Simberloff and Wilson..
Jim Costa writes of the research and insight shown by the two men who wrote first of natural selection. Darwin influenced by his journey around the world aboard the Beagle and Wallace by his collecting in the remote islands of the Malay Archipelago. Each was influenced by life seen on islands especially when compared to nearby mainland populations.
You should read whatever David Quammen writes!! Plain and simple.
In this book he collects a group of stories about islands and creatures. Large animals and small animals; explorers and thinkers. As expected there is Wallace and Darwin and Ed Wilson and Thomas Lovejoy and of course the Dodo of Mauritius playing important roles; but the story is in the telling and thanks to Quammen we are part of a grand exploration – into the stunning simplicity and complexity of our world.
This volume should be available in used book stores by now. It is the predecessor of the many books by Wilson and the one that sets the stage for much of his thinking and for our understanding of the complexity that adaptation brings. Specific habitats can be like islands; jungle adaptations, wetland or riverine or rock cliffs all are specific and in many ways isolated – each a small test; a laboratory for the future.
If you want adventure – travel with Hadoram. He lives out of a backpack. He carries a monster camera and he seems to be always at sea. This book is a field guide for sure, but it reflects the life and times of those creatures that rarely come ashore and the many creatures who never come ashore. It offers a close up look at the animals that have succeeded (so far) in adapting to oceanic life and the use of rocks and islands for nesting and resting.
The Galapagos Islands are variable; those in the east are worn and weathered, smooth and low, vegetated but tired. the islands in the east are volcanic and raw, jagged and tall, often barren but vibrant. The west is where the nutrients are, cold water upwellings, volcanic activities; sperm whales and lots of life. In the east they are a bit softer, quieter; but the east is where the albatrosses are and there is still a lot of life. Then there are the people; residents, fishermen, tourists, and scientists. It is because these are largely waterless islands that they remain so undeveloped. They could have been Hawaii or New Zealand – places where the natural world, the life that evolved there, is largely just a memory. Islands are cradles of evolution but can that dynamic be stalled or even stopped?
Guam presents a story that should make us all afraid. Pretty much all vertebrate life has been eradicated by a new resident. No in this case it isn’t humans, or rats, or cats, or goats – it is a brown snake. And, it is everywhere. This story exemplifies what happens on islands when things go wrong. In many cases (perhaps all islands have felt this blow over the millennia) the invasion is a natural phenomenon. In other case we bring the problem to the island.
So, we see islands forming and transforming. We see plates moving and continents rearranging themselves. But the explanations for how life reaches remote places and moves around the globe have been a bit glib and unproven. This book is a story of times and timings, of good fortune and dramatically bad luck. Riding a tectonic plate seems possible but not really says de Queiroz; a chance happening is possible, more likely, and frequent enough to actually explain how life moves over our earth. This is a good read.

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