alien earth

There are lots of lifeforms on the planet which have that touch of the weird and alien about them. The ocean and the insect world are teeming with them. But among the plant world there are plenty of odd specimen, and as regular readers of my blog know I love to photograph fungi.

We’re past the mushroom season, alas so I’ll have to wait until August/September before I can capture their odd glory again, but in the meantime there are always lichens!

Here’s a lovely duo I photographed recently. Due to all the storms we’ve experienced lately there are tons of branches and trees knocked down in the woods I frequent (well, the ones I can still reach – many are flooded out or inaccessible). It’s demonstrated to me how many of trees are laden with these free-loaders.

Lichens are an interesting amalgam of a fungus and one or more algae, which produces a stable, symbiotic partnership. They are found in pretty much every environment on Earth, even the most extreme, and some varieties can live to be hundreds of years old (apparently an example of an Arctic specimen of a crustose lichen, Rhizocarpon Geographicum, was found to be about 9000 years old).

The diversity is staggering. I’m putting up a select few I managed to photograph well, but there are an estimated 13,500 to 17,000 species of lichens in the world.

They are very sensitive to pollution, however. So I guess it’s a good sign if your tree or stone wall is heaving with them – although I’m sure many people view them as a nuisance.

Due to the standard rate of lichen growth we have Lichenometry, which is the “geomorphic method of geochronologic dating that uses lichen growth to determine the age of exposed rock, based on a presumed specific rate of increase in radial size over time.”

Phew! Not only are they strange, they are useful. (They have also been used for dyes, food, and medicine.)

And most people don’t even notice these wee bizarre miracles on a daily basis.

Lichens: one of Nature’s most successful team-ups.