Riding a Bike for Antibiotic Resistance Awareness

In 6 months, my friend Wesley Loftie-Eaton will cycle from Nairobi (Kenya) to Cape Town (South Africa). This epic trip is not only for the sake of adventure, but to raise awareness on antibiotic resistance and promote research in Africa. The first three blogs are already up and they are titled “Why cycling?“, “Why Antibiotic Action?” and “Why science in Africa?”.
A successful mission depends on promotion, so like, share, donate, subscribe, etc., to help Wesley in this important campaign.

His blog is here, go check it out!




To thrive in the twenty-first century, can we learn to steer evolution?

Cliff Swallow in flight

Cliff swallow in flight. (Flickr: Don DeBold)

Many of the biggest challenges humanity faces in the next hundred years are biological: dwindling wild lands and disappearing biodiversity, antibiotic-resistant bacteria, and emerging new viruses, but also feeding nine billion people or more a healthy diet in a climate-changed world. As Theodosius Dobzhansky famously remarked—and as this very website’s name proclaims—nothing in biology makes sense except in the light of evolution. So are there evolutionary answers to all these biological challenges? According to a big new review article just released online ahead of print in the journal Science, the answer is emphatically yes.

The long list of authors, led by Scott P. Carroll and including Ford Denison, whose lab is just down the hall from my office at the University of Minnesota, explicitly connect evolutionary principles to global goals for sustainable development. These include the reduction of both “chronic lifestyle” diseases and infectious diseases, establishment of food and water security, clean energy, and maintenance of healthy ecosystems. Carroll and his coauthors divide the applications of evolution to these problems into cases where evolution is the problem, and those where evolution may offer the solution.

Continue reading

Averting the Approaching Apocalypse

This post is a guest contribution by Dr. Levi Morran, NIH postdoctoral fellow at Indiana University. Levi studies the role that both coevolutionary relationships and mating systems play in shaping evolutionary trajectories. His research using experimental coevolution to test the Red Queen hypothesis recently appeared in Science and was featured on NPR and the BBC.

electron micrograph of the aerobic soil bacterium Pseudomonas fluorescens(photo credit http://bacmap.wishartlab.com/organisms/500)

Electron micrograph of the aerobic soil bacterium Pseudomonas fluorescens
(credit BacMap)

I’ll begin by acknowledging that the title of this entry is probably a bit more dramatic than it needs to be. Nonetheless it’s pretty catchy isn’t it?

Given that the human population seems to have survived that whole 2012 Mayan calendar thing without incident, I know several of my friends (I won’t name names, but you know I love you) that would immediately think about zombies upon reading this title.  However, I am not particularly concerned about the extinction of the human race at the hands of zombies. For one thing, I need more evidence (or in fact any evidence whatsoever) before I buy the whole “zombies will rise up and end us all” fear. Further, Max Brooks (son of Mel Brooks) has given us a hilarious and potentially mildly effective guide to surviving the zombie apocalypse. Ultimately I am far more concerned about bacteria. To avoid inducing mass panic, I’m not talking about a terrified level of concern here, but certainly concerned enough to give it some thought.

Why bacteria? Well, the human population is currently in an evolutionary arms race with many of the bacterial species that infect us.  We continue to hurl scores of antibiotics at bacterial infections, imposing very strong natural selection, with little regard for the evolution of antibiotic resistance in those bacterial populations. Using current strategies in medicine, we are forced to administer greater doses of drugs or develop novel antibiotics to combat infections as the bacteria evolve greater levels of resistance (Levy and Marshall 2004, Martinez et al. 2007). This is a vicious cycle. I believe it is time to develop new strategies of managing our pathogens and treating infections. Thankfully there are many people that agree and are conducting ground-breaking research in this area, like Andrew Read’s group at Penn State University.

A paper by Quan-Guo Zhang and Angus Buckling (2012) takes an experimental evolution approach to begin addressing this issue empirically. In search of a different strategy for curbing the evolution of antibiotic resistance in their experimental populations of the bacterial species Pseudomons flourences, Zhang and Buckling treated their bacterial populations with either antibiotics, a bacteriophage or “phage” (a virus that attacks bacteria), or a combination of the antibiotic and phage. Zhang and Buckling predicted that the combination treatment might be more effective than either antibiotics or phage alone because the combination treatments should better reduce bacterial population sizes and limit their response to selection (Alisky et al. 1998, Chanishvili 2001, Comeau 2007). Additionally, bacterial mutations that confer resistance to antibiotics generally do not also confer resistance to phage, so evolution of resistance to the combination treatments would likely require at least two mutations, and thus require more time to evolve resistance than the other treatments (Chanishvili 2001, Kutateladze 2010). Continue reading

Friday coffee break

Musical coffee

Every Friday at Nothing in Biology Makes Sense! our contributors pass around links to new scientific results, or science-y news, or videos of adorable wildlife, that they’re most likely to bring up while waiting in line for a latte.

From Noah: Paleontologists reconstruct the song of a fossilized Jurassic-era katydid.

Examining the insect’s seven centimeter long fossil wings under microscope, researchers were able to see how the prehistoric male katydid employed stridulation, i.e. rubbing body parts together, to produce a song to attract a female.

From Jon: A tranquilizer that is commonly abused as a club drug shows great promise for treating depression.

And the patient, they say, you know, yeah, it helped with my pain, but, you know, my depression seemed better. And so this was sort of a curiosity for a long time until a few years ago, when some folks at the National Institutes of Health decided that they really wanted to check this out.

From Sarah: The New York Times on the natural history of venomous mammals.

Every so often, however, a mammalian lineage discovers the wonders of chemistry, of nature’s burbling beakers and tubes. And somewhere in the distance a mad cackle sounds.

Skunks and zorilles mimic the sulfurous, anoxic stink of a swamp. The male duck-billed platypus infuses its heel spurs with a cobralike poison. The hedgehog declares: Don’t quite get the point of my spines? Allow me to sharpen their sting with a daub of venom I just chewed off the back of a Bufo toad.

From Jeremy: Antibiotic-resistant strains are now so widespread that we may soon see the day when gonorrhea is untreatable.

Gonorrhea is one of the most common sexually transmitted diseases in the world—with about 600,000 cases diagnosed in the U.S. each year. A few years ago, investigators started seeing cases of infection that did not easily respond to treatment with a group of drugs called cephalosporins, which are currently the last line of defense against this particular infection. Now, the number of drug-resistant cases has grown so much in the U.S. and elsewhere that gonorrheal infection may soon become untreatable, according to doctors writing in the February 9 issue of the New England Journal of Medicine. [Link sic.]

And, from Devin: Adrien Treuille discusses the power of online, collaborative puzzle solving for Google’s “Solve for X.”

Friday coffee break

Every Friday at Nothing in Biology Makes Sense! our contributors pass around links to new scientific results, or science-y news, or videos of adorable wildlife, that they’re most likely to bring up while waiting in line for a latte.

From Jon: Drug-resistant bacteria have been found on pork products raised without antibiotics. (But note that this doesn’t necessarily mean antibiotic-free farming is futile.)

The researchers found that 64.8% of the samples were positive for staph bacteria and 6.6% were positive for MRSA. Rates of contamination were similar for conventionally raised pigs (19 of 300 samples) and those labeled antibiotic-free (seven of 95 samples). Results of genetic typing identified several well-known strains, including the so-called livestock-associated MRSA (ST398) as well as common human strains; all were found in conventional and antibiotic-free meat. (The label “antibiotic-free” is not regulated, and the products were not “certified organic.”) [Hyperlink sic.]

From Sarah: New paleontological finds suggest dogs were first domesticated as long as 33,000 years ago. (See also The Onion‘s related person-on-the-street interviews.)

Researchers at UA and universities in England and the Netherlands used radiocarbon dating to determine that the skull of a Siberian dog was about 33,000 years old. Slightly older dog remains were identified in Belgium a few years ago by a separate research team.

Devin suggests Daniel Simons’s guide to scientific writing and revising.

Every section of your introduction should build directly on the previous ones, maintaining the narrative flow established by your opening. If your paper is organized as an unsolved mystery, each paragraph should add clues. If your paper is organized as a fiery controversy, each paragraph should add fuel. If a paragraph doesn’t contribute, cut it.

And finally, from Jeremy: some clever dissection work has revealed that, for orb-web spiders, mating continues even after the male’s intromittant organ breaks off inside his mate.

“It is quite remarkable,” says Jutta Schneider, who studies sexual interactions in spiders at the University of Hamburg in Germany. “It supports our notion that male spiders of some species are under selection to prolong copulation against the actions of the female.”