Tuesday, April 21, 2009

This Week's Sci-Fi Worthy Parasite

Now that I've grossed most of you out with my last week's pick, I think I'll go ahead and make this week's pest a little easier to look at.

The Rust Fungus Puccinia monoicaThe image looks like a mustard plant with nice, yellow flowers. But alas! It is actually the product of this week's parasite, the rust fungus Puccinia monoica.

The fungus infects mustard plants and completely changes their 'behavior' to facilitate its own reproduction. Firstly, the fungus infects the plant as a whole, stealing nutrients and generally acting like a parasite. But Puccinia is a sexual fungus - to reproduce it must combine genes with another member of its species. Of course, it's hard to mate when you're stuck on a stationary plant. So the fungus has evolved a unique (and impressive) means of getting laid.

The first thing it does is emit hormones which cause the host to stop flowering. Then it makes the infected plant create pseudoflowers from clusters of leaves. The pseudoflowers look almost identical to natural flowers, even in untraviolet light. And as if looks alone weren't enough to get the job done, the fungus' fake flowers also emit a strong scent and are sticky with a sweet substance that attracts insects. That, in the end, is the goal of these amazing mimics. Bees and other pollinating insects feed on the pseudoflowers, and in the process, they pick up the sperm and eggs produced by the fungus much like pollen. These creatures then land on another fake flower, thus transferring the genetic material and allowing the fungus to reproduce as well as infect other plants.

It's actually quite remarkable how well the fungus has managed to imatate flowers and get itself spread. Imagine a parasite spreading through the human population by castrating us and convincingly reproducing the look of our sexual organs... Maybe like a Cymothea, but not for our tongues. *shudder* If that's not sci-fi freaky, I don't know what is.


Stephanie B said...

A little less immediately threatening than last week's but talk about an idea for Science Fiction!

I have a novel set on a new planet. I'm taking notes, I promise you.

Thank you!

MuggsMcGinnis said...

I researched parasites for a science fiction story, specifically parasites that alter the host's behavior. Some are amazing and creepy:

A worm whose life cycle passes through caterpillars and birds. Bird poop, with parasite eggs, dropped on leaves gets consumed, along with the leaves, by caterpillars. After growing in the caterpillar, the worm moves to the caterpillar's head and takes control: the caterpillar stretches out from a twig and rotates its body in wide circles while the red worm expands and contracts. The caterpillars head color cycles red-green-red... Bird seems to find this enticing and thus, continue the cycle.

There's a fungus that uses ants to spread its spores. When the fungus is mature, it causes the ant to climb as high as it can (e.g. a tree top) and stay there. The fungal fruit grows out of the ant's head and the spores are more efficiently spread on the wind.

There are lots more, including how the ebola virus causes people, just before they 'bleed out' to panic and run around, seeking other people (perhaps for help). Ebola leaves skeletal muscles almost unharmed, while efficiently converting other cells to packages of concentrated (even to the point of crystallization) virus.

Sorry if this is too gross. I find it gruesome but fascinating. I've found that you can't get science fiction people together for 30 minutes without the conversation turning to the bizarre and/or gross.