Re: are there bacteria that eat lava and will they destroy the earth?

hi wayne,

Wowee! Bacteria eating the earth! It would make a great science fiction story for sure.

Ocean vents are fascinating places. They occur near deep ocean ridges, where the plates that make up the earths crust are moving apart - molten rock from below rises into the cracks and new land is formed. Around the vents, structures called "black smokers" are formed - these are like chimneys made from rock. The water around the vents is very hot indeed - up to 400 °C and we would find it very toxic, because it contains a lot of minerals like sulphides and heavy metals.

So it was pretty surprising to find that all kinds of creatures live around these vents, at high temperature and pressure in poisonous water and in total darkness, away from the sun. You mention bacteria - these are the basis of all life around vents. There are also microbes called archaea, which are similar to bacteria in many ways, but distinct enough to be put in a separate group. We call these organisms extremophiles: -phile means "to like" and so they like extreme conditions. We know that some of them grow happily at up to 120 °C and they can feed on the toxic minerals in the water.

The microbes convert minerals into other chemicals that more complex organisms can feed on. There are huge tubeworms up to 2 meters long, white spider crabs, giant clams and shrimp. See the links later in my answer for more about these.

So ocean vents are amazing places. However, the microbes are not actually eating the lava - that would be too hot for them and is not in a form that they can eat. They are feeding on dissolved minerals in the water that come out of the lava. In science fiction stories, the idea of organisms growing out of control and taking over the earth is very popular but it can never happen, because other factors (like the fact that organisms tend to eat each other) control the population.

Don't let that put you off though, I'm sure your story will be great. And I hope you see that real-life science can be even more amazing and interesting than science fiction.

Here are some links to ocean vents to lool at:

Neil