Tag Archives: evolution

Third Eye Blind let the RNC off pretty easy

Until this morning, I was not aware that Third Eye Blind is still a thing. That’s when I spotted the numerous headlines hailing the band’s heroic performance at some sort of RNC after-party. According to Vox, the band was guilty of “surprising guests with messages of gay rights and science and serenading them with some of the band’s more obscure songs.” Off with their heads.*

Continue reading Third Eye Blind let the RNC off pretty easy

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How the Marshawn Lynch got his wound: a heretofore untold Just So Story

Thanks to Rudyard Kipling, we know how the leopard got his spots, how the camel got his humps, how the tiger got his stripes, how the whale got his throat, and so on.* Among his beloved Just So Stories is one titled The Crab That Played with the Sea, which tells of how the crab was transformed from a large animal into a tiny one.**

Continue reading How the Marshawn Lynch got his wound: a heretofore untold Just So Story

Barack Obama has a secret weapon in his war against ISIS

That weapon: the Seattle Seahawks. Don’t believe me and/or have no clue what I’m talking about? As noted Seahawks fan Bill Nye* might say, Consider the following:

Continue reading Barack Obama has a secret weapon in his war against ISIS

Study shows that all dogs know exactly one trick

The latest installment on my trip down Science Friday lane, a segment from February 2011: Can Dogs Smell Cancer? My initial reaction was that this seems like something new and exciting — you can teach (old?) dogs new tricks:

Researchers in Japan say they have trained a Labrador retriever to sniff out cancer in people. Writing in the journal Gut, the scientists say the dog was better than conventional tests in identifying people with colorectal cancer.

The dog, named Marine, sniffed the breath and the stool samples of more than 300 people and had a whopping 98 percent accuracy rate, picking out the 40 people in that group who actually had cancer.

98% is pretty good, so I was curious to find out how far the field of study had advanced over the intervening two and a half years. But the only development I could turn up was a piece that appeared in this past May’s Penn Current, Penn researchers use dogs to detect ovarian cancer. The article started off with some helpful background:

When it comes to the sense of smell, dogs far surpass the capacity of human beings. Humans sniff out odors using about 350 different olfactory receptors, but canines utilize more than 1,000 to inhale a world jam-packed with smells, including the volatile organic compounds or odorants altered in the earliest stages of ovarian cancer.

But as I kept reading, I quickly discovered that in spite of the article’s title, dogs cannot yet detect ovarian cancer. Unlike the Japanese dogs discussed on Science Friday — who actually could detect one kind of cancer — the Penn lab’s detection ability is, for now, merely aspirational [bolded for emphasis]:

The ability to smell cancer is seldom used by doctors. But, combined with chemical and nanotechnology methods, Penn researchers hope to use dogs to develop a new system of early cancer screening that could save lives.

For this study, [scientists] will analyze tissue and blood samples from ovarian cancer patients. They will look for the chemical signature of the odorants from the patients, and check them against the volatile compounds emitted by healthy samples to confirm that they differ.

Currently, doctors use expensive diagnostic tools to detect ovarian cancer, instruments that still fail to find the cancer until it has reached an advanced stage. Tanyi says more than 70 percent of ovarian cancer cases are diagnosed in Stage 3.

If we could make a new screening method, it would be much easier to detect early stage cancer, and early stage treatment is much more effective,” he says.

It would seem that in two and a half years, science has progressed hardly at all. One day, dogs will be trained to sniff ovarian cancer — but we’re not there yet.

And while that might seem disappointing, it shouldn’t be all that surprising. After all, the original findings from Japan don’t seem so impressive in hindsight [pun intended, and will make sense momentarily]. Sure, the study found that dogs can detect colorectal cancer — but sniffing bottoms is the same trick they’ve been perfecting over the last 30,000 years of doggie evolution: Continue reading Study shows that all dogs know exactly one trick

Why I wouldn’t bet on Hope Solo’s babies

When Trey Griffey was born (in 1994), then-Mariners GM Woody Woodward mailed him a contract dated “2012”. And had Trey inherited his dad’s baseball talent, that contract would have probably been worth it.

Fast-forward to 2012. Check that: stay right where you are — it’s 2012 right now! for now.

As it turns out, Trey decided to pursue football over baseball — but no matter what sport he settled on, people remain interested in his progress because, in part, they believe athletic ability can be genetically inherited.

That belief is not without good reason. After all, Ken Griffey lived 20 years, and he begat Ken Griffey, Jr.… begat Trey. Nevertheless, it often ignores an important part of the hereditary process — you know, the part that supplies the other half of the child’s DNA. You see, I’m fairly certain Woody Woodward didn’t consider Melissa Griffey’s baseball skills when offering newborn Trey a contract.

And that’s an oversight. Trey chose football over baseball and will never play for the Seattle Mariners.

This evening, I came across an article in the Seattle Times, Jerramy Stevens released after arrest on suspicion of assaulting fiancee, Hope Solo. Now, I do not mean to make light of domestic violence. If the allegations are true, they are obviously serious – though I will note that, as of now, the couple still intends to wed this coming Tuesday. So without dwelling on the more unsavory aspects of the episode, I would like to focus your attention on the following tidbit of information I gleaned from the headline: former Seahawk TE Jerramy Stevens and Sounders goalie Hope Solo hope to one day soon be married. And for the sake of argument, I’m going to assume that the two plan to one day have kids.

Now, I don’t know much about Hope Solo, aside from her name, which means that she’s probably talented — and on that limited basis, it’s hard to characterize this marriage as anything but a disaster for her gene pool.

So before the Seattle Sounders Women sign New Hope Stevens through 2040, I would urge them to consider the identity of the (presumed) father. You see, Solo’s kid is going to make for one ineffectual goalie when the ball keeps slipping through her fingers:

Continue reading Why I wouldn’t bet on Hope Solo’s babies

Putting lipstick on a pig flu

On Friday, I wrote about the threat to human health posed by the emergence of antibiotic-resistant gonorrhea. In the process of writing that post, I learned – if nothing else – the correct spelling of ‘gonorrhea’.

Bring it, Snigdha Nandipati.

Then, yesterday, medical journal The Lancet published the first scientific estimate of the number of deaths attributable to the outbreak of swine flu in 2009. Turns out, the virus was much more deadly than originally thought:

Beginning in 2009, the virus swept the globe, and the WHO counted 18,500 swine flu deaths that had been confirmed by laboratory tests. But according to new estimates from researchers at the U.S. Centers for Disease Control and Prevention, the virus probably killed between 105,700 and 400,000 people around the world in its first year alone, and an additional 46,000 to 179,000 people likely died of cardiovascular complications from the virus.

– H1N1 Swine Flu May Have Killed 15 Times More Than First Said, ABC News

So I thought now might be an opportune time to repost an article I wrote in 2009 for The Summer Pennsylvanian, as relevant today as it was the day it was originally posted [6/4/2009]. Also, since it was in The Summer Pennsylvanian, I imagine nobody actually read it the first time. Please excuse the somewhat out-of-left-field conclusion to the article – I was encouraged to relate my topic in some way to on-campus developments:

Continue reading Putting lipstick on a pig flu

Gonorrhea: It’s what’s for dinner

When people discover I don’t eat meat, the follow-up question is standard: ‘Why?’

One of the most common guesses is health, for the typical litany of meat-related health risks: cholesterol, heart disease, obesity, and the like. I imagine my interrogators aren’t thinking of gonorrhea – but that answer might be considerably closer to the truth.

Earlier this month, the World Health Organization came out with a report that gonorrhea is gaining resistance to common antibiotics and may soon become untreatable. According to the AP:

“This organism has basically been developing resistance against every medication we’ve thrown at it,” said Dr. Manjula Lusti-Narasimhan, a scientist in the [WHO]’s department of sexually transmitted diseases. This includes a group of antibiotics called cephalosporins currently considered the last line of treatment.

Once considered a scourge of sailors and soldiers, gonorrhea – known colloquially as the clap – became easily treatable with the discovery of penicillin. Now, it is the second most common sexually transmitted infection after chlamydia. The global health body estimates that gonorrhea is responsible for some 106 million infections annually.

Gonorrhea is hardly the first infectious disease to acquire antibiotic resistance. The mechanism – natural selection – is relatively straightforward: the bacteria that survive antibiotic treatment due to resistance-conferring genetic mutation will pass those genes on to their offspring.

Furthermore, it is not a recent discovery. In a 1945 interview with The New York Times – the year that penicillin became available to the public – Alexander Fleming cautioned that the inappropriate use of antibiotics would lead to the propagation of resistant bacteria. When antibiotics are necessary to treat humans, they place caretakers in something of a Catch-22: sure, you can refrain from using them to protect their effectiveness, but then what’s the point of not using them? Fleming urged a cautionary approach, and suggested that penicillin be used only when necessary, only in sufficient quantity, and only for sufficient duration so as to completely eliminate resistant strains.

But where resistance in some bacteria, like Methicillin-resistant Staphylococcus arueus (MRSA), can be largely ascribed to over-prescription of antibiotics, or the failure of patients to self-administer them correctly, gonorrhea is thought to pick up resistance from bacteria it encounters in the wild – and the source of those ‘wild’ bacteria is no great mystery.

In 1949, Dr. Thomas Jukes, an employee of American Cyanamid, was experimenting with antibiotic use in agriculture. Antibiotics were already used to treat sick animals, but Jukes’ work led to a startling discovery: when he mixed subtherapeutic levels of tetracycline into the feed of healthy animals, they experienced a spectacular increase in growth.

Today, a full 90% of antibiotics used on farms are fed to animals subtherapeutically. Meanwhile, the total amount of antibiotics fed to farm animals has increased exponentially, rising from approximately half a million pounds by weight in the mid-1950s to just over a million in 1960, and reaching an estimated 24.6 million pounds in 2001. To put the amount under discussion in some perspective, the antibiotics used to treat sick humans in 2001 amounted to a measly three million pounds.

The consequences of this practice are predictable. Tetracycline, an antibiotic commonly fed subtherapeutically to livestock, provides an instructive example. The drug is not degraded by resistant bacteria, but simply expelled from the cell, into the bloodstream, and ultimately into the environment. Because of the molecule’s relative stability, it persists for a long time and continues to select for bacterial resistance. Tetracycline has been recovered from soils plowed with animal feces, as well as human municipal water supplies in both the United States and Europe.

When first introduced to the livestock industry, 5-10 parts per million (ppm) of tetracycline was sufficient to stimulate growth in cattle. Today, 50-200 ppm is necessary to achieve the same effect. It is tempting to believe that resistance is only a problem for the farmers who must buy ever-increasing quantities of tetracycline, but antibiotic resistance is hardly confined to the farm: a full 75% of the antibiotics fed to livestock pass into their surroundings.

In other words, antibiotics have become an ambient feature of the environment, where they raise the general level of resistance within the microbial community.

In one 2008 study, researchers tested eleven soil samples from distinct locations and discovered in each strains of bacteria that could survive eating nothing other than the compounds intended to destroy them. The antibiotic-eating bacteria – including Shigella flexneri, which causes diahrrea, and E. coli – hailed from eleven distinct orders of bacteria, and each of the eighteen antibiotic staples tested by the scientists could be digested by at least one species. The bacteria were able to survive in concentrations of antibiotics greater than one gram per liter, which is fifty times above the minimum level that typically defines antibiotic resistance.

And to make matters worse, bacteria would make excellent kindergarteners: they are very good at sharing.

Like any eukaryotic cell, bacteria have chromosomes. However, bacteria are unique in that they can also harbor plasmids, small circles of DNA that exist separately from chromosomal DNA. By traveling through a physical connection called a pilus, these plasmids can move not only between bacteria of the same species but between bacteria of unrelated species. In fact, plasmids are often made up of DNA spliced together from many different species to create a single transferable block of nucleic acid.

The existence of plasmids means there is no barrier between the bacteria harbored inside humans and those that inhabit livestock and the wider world. The gene pools are one and the same. And this fact is likely to play no small part in gonorrhea’s ability to acquire antibiotic resistance. Back to the AP:

Scientists believe … the gonorrhea bacteria’s astonishing ability to adapt means the disease is now close to becoming a super bug. Gonorrhea is particularly quick to adapt because it is good at picking up snippets of DNA from other bacteria.

In an environment awash in antibiotics, those other bacteria are all likely to harbor resistance to at least one antibiotic. Unsurprisingly, the list of drugs to which the ‘gonorrhea superbug’ is already resistant includes penicillin and tetracycline.

And here we run up against the underlying issue, which is that modern husbandry is literally dependent on antibiotics. The increased growth the drugs provide is crucial to maintaining beef producers’ slim profit margins. Meanwhile, Concentrated Animal Feeding Operations (CAFOs) – where today’s cattle are fattened on a diet of unfamiliar foods – are built to contain as many livestock as possible. Where subtherapeutic antibiotics were introduced to stimulate growth rates, they are now indispensable agents of disease control.

The WHO report skirts around this issue: a scan of the report turns up exactly zero instances of the terms ‘farm’, ‘animal’, ‘subtherapeutic’, or other related search terms. Its core recommendations focus almost exclusively on treatment and prevention of the disease, a valuable contribution, but one that does not engage the underlying causes of resistance development:

  • advocacy for increased awareness on correct use of antibiotics among healthcare providers and the consumer, particularly in key populations including men who have sex with men (MSM) and sex workers
  • effective prevention, diagnosis and control of gonococcal infections, using prevention messages, and prevention interventions, and recommended adequate diagnosis and appropriate treatment regimens
  • systematic monitoring of treatment failures by developing a standard case definition of treatment failure, and protocols for verification, reporting and management of treatment failure
  • effective drug regulations and prescription policies
  • strengthened AMR surveillance, especially in countries with a high burden of gonococcal infections, other STIs and HIV
  • capacity building to establish regional networks of laboratories to perform gonococcal culture, with good-quality control mechanisms
  • research into newer molecular methods for monitoring and detecting AMR
  • research into, and identification of, alternative effective treatment regimens for gonococcal infections

So while the WHO Report on antibiotic-resistant gonorrhea skirts the role of livestock, it has at least given me the opportunity to point out the industry’s success in externalizing much – if not most – of the true cost of its harmful practices. Yes, ceasing to administer antibiotics to livestock at subtherapeutic levels would raise the price of meat. It would also bring the price meat better into line with its true cost.

So if you’re ever fortunate enough to experience that burning sensation while ‘going about your business’, please remember: it’s just the cost of doing business.