Lava, Land, and Life Forms

The dramatic eruption in Hawaii has brought to mind the unstoppable power of volcanoes to destroy pretty much anything in their path. But though the cataclysmic power of volcanoes usually takes precedent, it’s worth taking a moment to appreciate their role as ecological changemakers—albeit, forceful ones.

Since last Thursday, the eruption at Hawaii's Kilauea volcano has been spewing hot lava into previously inhabited areas, forcing the evacuation of more than 1,800 people. The devastation has destroyed homes in its path, sending plumes of smoke and noxious sulphuric gases into the air. Thankfully, no injuries or fatalities have been reported so far, due in large part to warning earthquakes as the lava rumbled beneath the Earth leading up to the eruption.

While it’s certainly a stark reminder of the havoc that natural disasters can wreak on our once-stable cities and towns, it’s also a reminder of the irrepressible power of volcanoes—one that, like floods, hurricanes, and tsunamis, is just no match for the safeguards we put up against them. Terrible as they may be for human settlements, volcanoes play a fascinating and bizarre role in biology. Probably most important of all, they are the great ecological unifiers: by razing the earth, they create new space for the microbes, plants, and animals that will undoubtedly follow.

The life that thrives near or in the wake of volcano eruptions is, frankly, startling. For one, volcanoes, in their violent yet mesmerizing beauty, are usually the harbingers of soil rich in nutrients and minerals. This is one of the reasons why the region around Naples, Italy, is so agriculturally productive—under the shadow of Mount Vesuvius, which famously killed thousands of people when it erupted in 79 AD, fig trees and grapevines spring up like mushrooms in the dark, loamy volcanic soil.

Another notorious monster volcano, Mount St. Helens, killed 57 people and millions of animals, both livestock and wildlife, in May of 1980. Despite this destruction, the eruption left in its wake a trail of new life—just a year after the eruption, scientists discovered a lone lupine plant growing on its slope, blown in to that strange new world by the wind. Since then, scientists have flocked to the site as an ideal laboratory to study the concept of succession, or the gradual process of change that occurs in natural communities over time. There’s even a dedicated Mt. St. Helens Lab.

There is also the legendary Hawaiian Ohia Lehua tree, so named for the lovers who are thought to be entrapped in its branches and flowers forever. Among the black basalt ash, Ohia Lehua trees are often the first to crop up after a volcano, their red flowers pushing through new cracks in the lava before it even cools.

But perhaps the most famous of volcano ecology stories is that of Krakatoa, an enormous eruption that killed some 36,000 people in 1883. The disaster occured on the tiny island of Krakatau, a desolate 5-mile-long protuberance with no inhabitants. It’s been reported that the dying throes of the volcano created the world’s loudest natural sound—a sound so enormous that it could have been heard by one-thirteenth of the globe.

As mariners and sheep ranchers looked on, clouds of ash plumed over the volcanic peaks of the Sunda Strait, a torrent of pumice rained down on the island, accumulating a 98-foot-thick layer of uninhabitable volcanic rock. The event triggered a 1.2 degrees Celsius drop in global temperature by blotting out the sun with ash. But since that fateful eruption, the island has become a goldmine for biological research, with colonizing species likely first brought in by the wind or by birds’ poop. In 1927, the new island of Anak Krakatau, or "Child of Krakatoa" in Indonesian, emerged from subsequent volcanic eruptions, providing a perfect comparison site to study the effects of the eruptions over time.

Even more, volcanoes create sites of severe contrast. For volcanologists, geologists, ecologists, and really, any other -ologist who wants in, volcanoes are environments that tend to bend the rules of biology and other systems. There’s the dramatic kipuka trails of Mauna Loa—often referred to as “living laboratories for evolution,” thanks to the lava that encircled (but never touched) them, carving out tiny, isolated islands on which species could evolve without any breeding or genetic mixing with other populations. It’s like the Galapagos, but if the ocean was lava.

Finally, consider the infamous tomato plant of Surtsey, at the southernmost point of Iceland. The imprudent plant is a perfect demonstration of the stark contrast between barren volcanic ash and a burst of new life. The explosively volcanic island, only in existence in its present shape since the 1960s, was named a UNESCO World Heritage site for the unique biology it has attracted since the eruptions. And perhaps most interesting of those new life forms was this tomato plant, the first colonizer in a barren land. After careful inspection, scientists realized the plant was growing in a pile of human poop, likely brought in by a visiting scientist or interloper.

Then again, it seems like any form of life would have a chance amid such cleared land and all that sweet, sweet volcanic soil.

Back at Hawaii’s Kilauea volcano, not much can grow so long as its fissures are still erupting. But after a little while, once the lava cools, the toxic “vog” (volcanic fog) that’s been accumulating in the air dissipates, and the seeds return, those lava flows might just become lush gardens and rich habitats.

That is, until the next eruption.

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