Summer Assignment: 7.29

Respect For the Fungus Overlords

Only one link today, it is a longer article and I am going out of town (again) tomorrow, and still need to pack...

Carl Zimmer is one of my favorite science authors/bloggers, there is a link to his blog The Loom on the left side of this blog. I recently read his book Parasite Rex, which was about how parasites are integral parts of ecosystems, and in many ways have directed the evolution of their hosts. One idea is that parasites are responsible for the evolution of sexual reproduction, which is actually quite costly and the reasons for it first appearing are unknown.

One thing that is made very clear throughout the book is that a parasitic life style may actually be the "norm" on Earth, rather than something odd or strange. Parasitic life forms may very well be found to outnumber "free-living" organisms.

This particular article highlights some current research on a fungal parasite (Ophiocordyceps unilaterius)of a specific species of ant (Camponotus leonardi). This parasite takes over the body of the ant and causes it to seek a high leaf. From there, the fungus grows out of the ant body and releases spores the forest floor below, which are then able to infect more ants.



The researchers wanted to know if the parasite was actually controlling the ants, or if the ants just got lost along the way, since ants normally do not occupy the specific leaf height where infected ants go to die and release the fungal spores.

And for those of you who may think this research qualifies as frivolous or wasteful,

Like their hosts, parasites face many threats to their survival these days. Just as overfishing may wipe out my dear namesake tapeworm, I worry about the rampant deforestation of tropical forests, which may wipe out not just trees, but the insects that depend on them, and the fungi that depend on them in turn. We should not wish extinction on Ophiocordyceps, as gruesome as it may be. It has much to teach us. We might even borrow some of its tricks–Ophiocordyceps antibiotics show promising signs of fighting against malaria and cancer. And it would be a true shame for this particular bit of science fiction to disappear from the world of science fact.

Also, parasites are just way creepy-cool. If you don't take my word for it, check out the book.

Quick Comment

Just a quick note that I will be out of town, with no internet access, from Friday morning till Sunday night/Monday morning. If you make a comment between those times, it may take a few days to show up. I will read them all when I get back.

Summer Assignment Post for 7.22

Lots of great comments last week...seems like everyone likes to curse when they hurt themselves, and are somewhat skeptical of using rapamycin to increase life span.

Remember to vote in the polls if you have not, and to check back for other student comments all week; the comment section can be a great place for discussion/arguments.

Seemingly "Duh!" Scientific Studies Often Hold Value

I actually looked up one of the studies mentioned in this article: the one about the evolution of tickle-induced laughing. Granted, that may have been just because I had an image in my mind of a bunch of grad students in a lab tickling baby chimps and gorillas, and that made me happy.

And I also found their model of the evolution of this laughter to be interesting...



If you haven't heard this before, you definitely will this year in AP: Everything in Biology can be explained through evolution.

In regards to the original article, do you think there are "frivolous" scientific studies? Or is any and all knowledge worthwhile, simply for the sake of knowledge?


Coping With Excess

I thought this was an interesting idea...will humans eventually evolve to be able to handle Big Macs and not get obese? Not sure... the columnist makes a lot of good points, but I think the most important one may be one of the last ones:

Many factors — what you eat today, what you ate as a baby, levels of exercise, your gut microbes and so on — contribute to obesity.

Something very important to remember, all traits, especially human traits, are very complex and hard to ascribe a cause to.

And the pentailed tree shrew looks like a pretty cool guy...even if there is only the one picture of him.

Summer Assignment Post for 7.15

This is the first "official" post for the summer assignment. Take a few minutes to read the linked articles below and make a comment or two on them. You don't need to read all three or comment on all three to get credit...just read whichever ones interest you. Be sure to check back often during the week after you have posted your comment, as you may want to respond to other student's comments, or they may specifically address your comments.

Also, if you have not voted in the two polls on the left side, please do so. The polls are anonymous, so you will not be singled out for your responses.

Darwin's Mystery of Appearance of Flowering Plants Explained

Two ecologists present a possible explanation for the rapid (in evolutionary terms) expansion of angiosperms in the Cretaceous period (100 - 65 million years ago). This problem upset Charles Darwin greatly, and he had no explanation for it when he proposed his framework for evolution by natural selection. I have an essay around here somewhere that goes into more detail about angiosperm evolution, but I am not sure where it is right now....

Anyone have any comments/thought about the mechanism proposed in this article?


A Pill for Longer Life?

Rapamycin, a drug commonly used in humans to prevent transplanted organs from being rejected, has been found to extend the lives of mice by up to 14% — even when given to the mice late in life. [...]until now, the only robust way to extend life in mammals has been to heavily restrict diet.

In terms of the average US life span of 78 years, this would add about 10 years. Would you take a drug that may increase your life span if it meant that you may be more susceptible to infections?


Holy $@%#! Swearing Eases the Pain

I thought this was kind of interesting...but I don't need you to make a list like the researchers had their subjects do.