Fungal infection? Try drying out for a while

So fungi have made the cover of Science, as parasites of bdelloid rotifers. The rotifers, which are metazoans, are asexual. So the question being addressed by these researchers is, how have these rotifers survived their pathogens for millions of years without the benefit of sexual reproduction? Sexual reproduction is considered by most biologists to be a key component of evolution, as without genetic recombination, natural selection cannot act. The answer they found is anhydrobiosis, or living without water. The rotifers are able to survive dessication, while their fungal pathogens aren't. The longer the dessication, the fewer pathogen propagules survive. The dessication also makes the rotifers lighter, which enables them to be dispersed through the air to escape.

I think there are a lot of answers to the question of asexuality within the fungi themselves. There are many, many lineages of fungi which have apparently lost the ability to undergo sexual reproduction. Like so many corners of mycology, there are several terms applied to them, Deuteromycetes (an older terms), Imperfect Fungi, or Mitosporic Fungi (cf. Meiosporic Fungi) to list three. Asexuality has developed in many fungal lineages, that is to say, the Deuteromycetes are polyphyletic. Or to say it another way, asexuality has arisen several times over evolutionary history.

Highlights of the root dig

Spent a good part of last week digging roots over in Georgia. My dissertation is a study of the decline of longleaf pine (Pinus palustris) and the role of Leptographium spp. and their insect vectors. What that means is I spend a lot of time collecting small beetles and "rolling" them to find out what fungi they're carrying. And it also means I go out and occasionally dig up some pine roots to see what fungi the insects may have introduced into the trees.

When digging roots, we also collect soil to see if the fungi may be just hanging out in the soil next to the roots (they usually aren't), and a few other things to try and figure out how the trees have been affected by the fungi and insects. This particular root, above, is notably munched up by insects. All those little white bits are where the insects chewed in and pitch came running out.

Another highlight of the root dig was coming upon this critter, a pine snake.
What do pine snakes have to do with fungi? If you'll indulge...
Red Cockaded Woodpeckers are an endangered species. Lots of folks around here hate the little bird because it ties 'em up in lots of "green tape". They are endangered because their preferred habitat is longleaf pine forest, which used to be all over and is now quite rare. This is the only woodpecker, so far as I know, that makes its nesting cavities in live trees. Why make your house in a live tree? Because of these pine snakes, which can climb a pine tree and raid your eggs. The woodpecker pecks holes around the entrance to the cavity to release the resin which acts as a deterrent to the snake. Eww! Sticky snake!
But where do the fungi come in? So the woodpeckers also prefers trees that are infected with Phellinus pini, which is a wood decay fungus causing a disease called red heart, which breaks down some of the cellulose in the wood which makes it easier to excavate. Hey, if you had to dig your house out of a live tree with your face, wouldn't you want the softest tree possible?

Then I had to head back out to the woods on Monday, to collect insects, and I came across this little guy. Not sure, but I think it's a baby cottonmouth. I'll get back to you on that.