Over at the collaborative science blog Nothing in Biology Makes Sense!, guest contributor Levi Morran examines the processes by which bacteria can lose genes over generations of evolution.
In a recent paper, Lee and Marx (2012) test both how and why they observe large-scale patterns of gene loss in their experimentally evolved populations of Methylobacterium extorquens. They evolved these bacterial populations under different treatments of resource availability (realms of specialization) and found that all replicate populations adapted to their specific treatment over 1,500 generations. During experimental evolution, 80% of the bacterial populations exhibited nearly a 10% reduction in genome size, and many of the gene losses occurred in similar regions of the genome, some even across treatments.
In case you think I was kind of an asshole in my response to that study about female vulnerability and sexual explitability (and, fine, I was; but I’d like to think I was channeling my natural asshole-ness for a righteous and scientifically important cause), here are some non-scientists taking many of the same issues with that very study, and coming up with even more basic questions about its logic:
I had a great run this morning! As noted yesterday, it was the 2012 Minneapolis Marathon. My final time was 3:33:37, which isn’t the personal record I’d hoped for on a flat course in nice weather, but I’m happy with it.
I took my iPhone with me, and tweeted photos along the course. And, just for the heck of it, I’ve put all the tweets (and encouragement/kudos/responses) together with some additional notes and context in a Storify. Enjoy!
Jeremy runs the 2012 Minneapolis Marathon
26.2 miles, tweeted.
Storified by Jeremy Yoder · Sun, Jun 03 2012 16:20:50
The 2012 Minneapolis Marathon was my fourth marathon, and my first springtime one. A mild winter made the training-up a lot easier, and the early June race date meant the weather should was tolerable, before everything goes all Minnesota-tropical for the summer. And, since I took my iPhone along for run-time tunes and podcasts, I could live-tweet photos of the course as I ran!
Long run tomorrow http://nblo.gs/yjHZQJeremy Yoder
And folks offered good wishes and advice:
@JBYoder good luck. Remember hydration is your friendDr. Wrasse
Thanks! And, always. RT @labroides: @JBYoder good luck. Remember hydration is your friendJeremy Yoder
Also, I did some carb-loading. Too much? Turns out it wasn’t.
Even though I’m running a marathon tomorrow morning, that double slice of leftover chocolate cake was probably a bad idea. #CarbOverLoadingJeremy Yoder
@JBYoder Naaah…plenty of time to digest. Good luck! More important: have fun! :)NatC
@SciTriGrrl Thanks! I’m sure I’ll be glad of the glycogen tomorrow morning.Jeremy Yoder
@JBYoder Well good luck!Giuseppe Gangarossa
I woke up at 5 a.m. to grab breakfast, then walked to the starting line in downtown Minneapolis. I love the view from the Hennepin Bridge.
Walking to the marathon. http://pic.twitter.com/rFtBIZYLJeremy Yoder
I got to the start a bit after 6 a.m., and people were already gathering.
http://pic.twitter.com/d4HaZSieJeremy Yoder
Ready to go, in … 19 min. http://pic.twitter.com/HFNvEbgcJeremy Yoder
@JBYoder good luck!Bastian Greshake
http://pic.twitter.com/RAvZro60Jeremy Yoder
At 6:30 a.m. on the nose, we were off. We ran through downtown, then turned down onto the riverfront road, first heading north to Broadway for a turnaround. And then it was long way south. My playlist was
“Olympic Fanfare and Theme,” by John Williams, which is great for that starting motivation.
“Barbra Streisand,” by Duck Sauce—good for setting up a pace in the first mile.
The Slate Political Gabfest, because I listen to podcasts on all my training runs, and so they go in my marathon playlist, too.
And then, about an hour in, I remembered to take photos.
And then another podcast, NPR’s new puzzle show Ask Me Another, which provided some welcom distraction in the third hour.
Here’s the actual Fort Snelling, I believe. This was right after a hill that regained something like 75% of the elevation we’d lost on the way down to the river in maybe 300 meters. That slowed everyone waaay down.
http://pic.twitter.com/mVEUSbNNJeremy Yoder
Loving @JBYoder’s photos from his marathon this morning. Run, Jeremy, run!science_goddess
Mile 21: I’m definitely slowing down.
http://pic.twitter.com/9EwEmJP9Jeremy Yoder
No more podcasts, now. The playlist is entirely devoted to tracks that’ll help me keep putting one foot in front of the other. And my motivational music skews nerdy, as you might guess:
“To Boldly Go” and
“End Credits,” both by Michael Giacchino, from the soundtrack of the latest “Star Trek” movie.
For the home stretch, I have Cake’s cover of “I Will Survive” in the playlist, and boy do I need it. It’s gotten hot! But here comes the Washington Avenue Bridge …
http://pic.twitter.com/irXAwAqpJeremy Yoder
And finally, the finish line. Appropriately enough, I crossed to “River Crossing,” from Carter Burwell’s awesome soundtrack to the Coen brothers’ awesome “True Grit.”
About 3:33. http://pic.twitter.com/PHFTUI4KJeremy Yoder
My final time turns out to be 3 hours, 33 minutes, and 37 seconds. Not a personal record, but not too shabby. The finisher medal is pretty nifty, too:
And I’m still alive. http://pic.twitter.com/PdJYXcS7Jeremy Yoder
And then, as soon as I was rehydrated, it was off to clean up for brunch with friends over in Saint Paul. Not a bad way to spend an early-summer Sunday, all things concerned.
Some more comments/kudos from the tweeps—thanks, everyone!
@JBYoder Congrats! Now please tell me that’s the white balance on your camera and not sunburn.Stephanie Zvan
Yeah, that was mostly the white balance. Although I was shirtless from about mile 17 on. The nice thing about a cheap tank top is you can ditch it when it gets sweat-logged and chafe-y.
Nicely done! Makes me wonder what I’ve been doing for the last 3.5 hrs RT @JBYoder: About 3:33. http://pic.twitter.com/4lkUFOPDRyan Kitko
@JBYoder congrats!! Great time!!NatC
Congrats! RT @JBYoder: And I’m still alive. http://pic.twitter.com/Yz3ET5wCGerty-Z
@JBYoder looks like it was a pretty scenic route. Congrats on your 4th Marathon! wish i had that dedicationJonathan Yoder
@science_goddess @Patrick_Clarkin @Bonovox1984 @SciTriGrrl @GertyZ @szvan Thanks for the encouragement! Made carrying my iPhone worth it!Jeremy Yoder
@GertyZ @JBYoder Woot!CackleofRad
@GertyZ @JBYoder (I think he just logged his #r4p)CackleofRad
Live-tweeting the running of a marathon?! @JBYoder is using lots of pictures to do it. Seems to be working. http://pic.twitter.com/OBVl7QUHRichard Harper
Live-tweeting the running of a marathon?! @JBYoder is using lots of pictures to do it. Seems to be working. http://pic.twitter.com/sytmQqRablake56x2
Next question: will my legs un-stiffen fast enough for me to get up the nerve to register for the Twin Cities Marathon in October?◼
Anyway, if all that doesn’t make you immediately want to watch, or if you’re about to leave a comment asking what, exactly, is a “redshirt,” then you probably should just wait for the next post.
*Caution: that link also includes a video of Scalzi covering the song on a ukelele, for which I refuse to vouch.◼
Specifically, the Minneapolis Marathon, which will be my fourth. Weather looks to be perfectly clear, and we’ll start at 6:30 in the morning, when it should be nice and cool. The course is basically my favorite regular training route, down along the riverside. With any luck, I might even get a personal record out of this.
I don’t know if I could watch a whole feature film like this, but it’s mighty pretty in two minutes-plus of full-screen viewing. And hey, just as I was wondering if there would be Joshua trees, there were Joshua trees.
And check out the casting: Hugh Jackman is Jean Valjean (yay!), Russell Crow is Javert (um, okay). The Thénardiers will be played by Sacha Baron Cohen and Helena Bonham Carter. And in a particularly nice touch, the Bishop of Digne will be played by Colm Wilkinson, who was Valjean in the 1985 cast.
This week at the collaborative science blog Nothing in Biology Makes Sense, guest contributor Kathryn Turner discusses how evolutionary processes determine whether an introduced species becomes an invasive species.
First, most obviously, how is it that a species is able to come into a new environment that it is not adapted to, surrounded by new environmental conditions and foreign biological interactions, and thrive? Thrive so exaggeratedly, that it can out-compete and displace species which have been there for millennia, adapting precisely to those environmental conditions and biological interactions? How can an individual survive to propagate a population? How can any species accomplish this? Second, less obviously: why can’t more species do it? Humans transport animals and seeds (and spores and larvae, etc, etc) around all the time, but only 10% establish self-sustaining populations, and only 1% spread to new habitats, becoming potentially invasive; this is known as the ‘tens rule’ (Williamson 1993) – a funny ‘rule of thumb’ for which I could never quite figure out the math.
For the answers, or at least some ideas about possible answers, go read the whole thing.◼
A Biologist went down to the coffee shop one day, because the walk out to the edge of the University campus provided some brief respite from the laboratory. Along the way the Biologist encountered an Evolutionary Psychologist, who was also going to the coffee shop, and they fell to walking together.
As they entered the coffee shop, they found it crowded with undergraduates, for it was almost Finals Week. Accordingly, they joined the long queue of prospective customers waiting to place an order. Said the Evolutionary Psychologist to the Biologist, “My dear colleague, do you not see this crowd of fertile young people as I do, engaged in a dance of mate selection and competiton that predates our ancestors’ descent from the trees?”
And the Biologist replied, “I don’t believe that our ancestors had access to steamed milk and espresso. Or free wi-fi.”
“You are being amusingly obtuse!” chortled the Evolutionary Psychologist. “The environment may have changed somewhat since the days of our Darwinian origins, I will allow, but ova remain much dearer than sperm cells.”
“That much is certainly true,” said the Biologist. “But I am not sure how much it matters to the coffee-shop flirtations of undergraduates, almost none of which will result in procreative intercourse.”
“Ah,” said the Evolutionary Psychologist, “Perhaps this is a subject wherein my own field has surpassed the expertise of yours, my dear colleague. For instance, we have recently discovered [PDF] that men are more attracted to unintelligent, inattentive women—precisely what one would expect if men have been naturally selected to seek out easy opportunities for impregnation. And this search is doubtless underway all around us at this very moment.”
“That is a remarkable and possibly misogynistic hypothesis,” said the Biologist. “I am most curious to know how it was tested.”
“O! It was most elegantly done,” said the Evolutionary Psychologist. “Some of my colleagues simply asked a small class of undergraduate psychology students—males, of course—to examine photographs of women which were previously selected for their various appearances of vulnerability, and tell whether the photographs indicated vulnerability to sexual exploitation, suitability for a one-night stand, and suitability for a long-term relationship.”
“I see,” said the Biologist.
“Most surprisingly,” continued the Evolutionary Psychologist, “My colleagues discovered that the young collegiate males felt that women who looked drunk, or were standing in compromising postures, or indicating vulnerability in any of a dozen different ways, were both more vulnerable to sexual assault and more suitable for a brief sexual dalliance—but not more suitable for matrimony.
“So you see, my dear Biologist, it is not we Evolutionary Psychologists, who proposed the hypothesis of sexual exploitability, that are misogynists—the only misogynist here is Natural Selection itself, which confirmed our hypothesis.”
“I must beg your pardon, dear colleague,” said the Biologist, “but I am afraid I do not understand the basis for your conclusion. In order for this discovery to have any bearing on reproductive success, is it not the case that most human reproduction would need to occur via coerced intercourse?”
“I must confess that this seems to be what the data indicate,” replied the Evolutionary Psychologist. “But we must not conclude therefrom that all men are rapists! By no means, dear colleague. I think it is quite plain that this result demonstrates no more then that all men are potential rapists.”
“But I remain perplexed!” said the Biologist. “Surely rape is an inefficient way to reproduce, since babies traditionally require a good deal of care after impregnation, and women have long known how to un-plant unwanted seeds.”
“That,” said the Evolutionary Psychologist, “is an important question to be resolved by additional study! But of course it need only be the case that the occasional coercive impregnation could increase a man’s reproductive success, however slightly, for Natural Selection to grab hold.”
“I suspect,” said the Biologist, “that you attribute greater efficiency to Natural Selection than this evolutionary force truly possesses, my dear colleague. But even if drunken collegiate hook-ups were a viable avenue for procreation, you must concede that there would needs be some genetic basis for the tendency to reproduce in this fashion, if Natural Selection is to act upon it. Do you truly believe this to be the case?”
“What a peculiar question!” exclaimed the Evolutionary Psychologist. “I thought that you Biologists were well aware that, in the absence of evidence to the contrary, it is quite safe to assume that any and all aspects of human nature have a heritable genetic basis. Would you truly require the demonstration of heritability in order to conclude that an observed trait or behavior is adapted by Natural Selection?”
“Indeed we would,” said the Biologist. “Such a demonstration, in the case of a tendency to sexual coercion, would be considered most remarkable in its own right, in the scholarly journals of my discipline.”
“What a boring and backward discipline you practice!” said the Evolutionary Psychologist. “Truly, it is no wonder that your field has seen no great advance this last half-century, even as we Evolutionary Psychologists dissect the very nature of humanity.”
“Your ambitions,” said the Biologist, “are indeed remarkable.”
At this juncture, the two colleagues found that they had reached the front of the queue, placed their orders, and went their separate ways.◼
References
Goetz, C., Easton, J., Lewis, D., & Buss, D. (2012). Sexual exploitability: Observable cues and their link to sexual attraction. Evolution and Human Behavior DOI: 10.1016/j.evolhumbehav.2011.12.004