Friday, February 28, 2014

Birdbrains

Although I’ve spent the majority of my adult life swearing off pets, in December I broke down and officially became a pet owner. An avid birder for the past few years, I decided birds would be a nice addition to the house. I love watching them and listening to their calls, and they’re pretty light on maintenance, so I took the plunge and bought a pair of lovebirds.
They’re beautiful. I don’t know their sex (DNA required), so I gave them boy names. Tuukka and André make a lovely pair (we are big supporters of gay marriage). They are named for two of my favorite NHL goalies: Tuukka Rask (Boston Bruins) and Mark-André Fleury (Pittsburgh Penguins) and I can tell you, for a pair of lovebirds, they certainly battle like a couple of hockey players.

I’ve spent considerable time training them over the past few months and they’re finally to the point where they no longer remove a hunk of my skin when I pick them up, which is a big improvement. They’ve learned how to return to their cage on my signal, which they accomplish by running up a ladder (hilarious), and they are now content to sit on my shoulder and watch TV (they seem to enjoy the NHL).
They are very smart. Lovebirds are basically miniature parrots, which are known for their intelligence. But it amazes me that a brain that small can function so efficiently; especially since they lack the complexity of human brains. So I did a little research to get a feel for what makes up a bird brain.

Bird brains contain many of the same structures as our brains. As in human brains, their medulla controls basic bodily functions: heart rate, blood pressure, and respirations. Like us, they have an optic lobe, but theirs is more developed than other vertebrates, since they rely strongly on vision. Their cerebellum, like ours, controls coordination and balance, but again, tends to be large, since it must coordinate the muscles involved in flight. And their cerebrum contains lobes, which tend to be larger in parrots and crows, compared to other birds. These lobes enable parrots and crows to be very adept with their beaks, which they use to manipulate objects. Parrots are also pretty agile with their tongues, a skill my lovebirds enjoy showing off by spitting shells out of their cage (which I’m pretty sure they do just to annoy me).

Tuukka and André have distinct personalities. Tuukka tends to be more aggressive and has been harder to tame than André. Tuukka entertains himself by shooting me the evil eye and pooing on my shoulder, while André is content to hang out and nibble on my earring. Aggression in humans is controlled by the amygdala, which causes it, and the hypothalamus, which regulates it via receptors that interact with the neurotransmitters serotonin and vasopressin. Bird brains contain both structures, so I wonder if it’s the same for them. If so, I’ll have to see about getting Tuukka some serotonin supplements…

It was once believed that the three capacities separating humans from other animals were bipedalism, language, and tool use. Although we are the only obligatory bipedal primates, language and tool use present a vaguer division. 

Studies among chimps and gorillas have shown they have the capacity for language, although at a more rudimentary level, and many animals communicate via distinct calls, which some consider a form of language.
The copycat speech of parrots used to be considered simple mimicry, but new studies have shown that parrots can actually construct meaningful statements, count, and even understand the concept of zero. Alex, a famous parrot who was the subject of experiments in avian intelligence, shocked his assessors when he answered “none” when asked how many blue keys were among a group of green and red. He was right!

As for tool use, it is now well documented among the animal kingdom and it just so happens some of these animals are birds.
The woodpecker finch, found among the rocky landscapes of the Galapagos Islands, uses twigs to extract insects from the insides of trees. But he doesn’t just use any old twig. He chooses an appropriate stick and trims it to the proper size before using it as a miniature pry bar to dig for bugs hidden within the bark. Crows show remarkable talent when it comes to constructing tools. They not only make tools, but can preplan and problem solve -  which is more than some humans can accomplish… And I’ve watched my birds use their beaks to hoist objects out of their way. They’re not only smart little suckers but strong, to boot!

And I’m convinced my lovebirds dream. Every now and then, in the still of the night, one of the birds will utter a blood-curdling “CHIRP!!” before settling back to sleep. What is he seeing in his little bird nightmare? A pouncing cat? My menacing hand reaching into his cage? What frightening images do their little brains conjure?
Birds and primates parted evolutionary ways over 280 million years ago and as we evolved along our separate paths, so too did our brains. As humans, we may be intelligent, but we certainly don’t own it. Pigeons can memorize over seven hundred different visual patterns. Scrub Jays exhibit episodic memory. Owls learn the many night sounds that lead them to meals. And African grey parrots can understand numerical concepts – a skill once thought to be uniquely human.

So the next time someone refers to you as a “birdbrain,” take it as a compliment. Birds are pretty darn smart.

Think you're intelligent? Check out this crow...
And here's a good read on the subject (although I believe she borrowed my title...).






 








Friday, February 21, 2014

A Syphilitic Sequel

Last week, we discussed the fascinating history of syphilis. If you didn’t catch it (no pun intended), I advise you to give The Seeds of Syphilis a quick read (and then flog yourself for missing it). We’ll pick up where we left off:

It’s the dawning of the 16th century and syphilis is rearing its ugly head across Europe…

The earliest reports of syphilis date back to 1495. The French army had marched into Italy, laying claim to Naples and, once the fighting ended, the soldiers settled in to celebrate their victory, treating themselves to the bevy of prostitutes who accompanied their expeditions. In no time, the soldiers were debilitated by fever, rash, and muscle pain. Over the next few months, the disease progressed, rendering them unable and unwilling to fight. Many were sent back to France, where they subsequently infected their loved ones.

By 1500, the “great pox” was spreading like wildfire.
It accompanied da Gama’s voyages to Calcutta in 1498 (the perfect side dish to chingri) and within twenty-five years, folks in Africa, Japan, and China found themselves grappling with genital sores. Even the islands of the Pacific fell victim. For centuries, syphilis plagued much of the known world. So let’s take a look at some of the ways society dealt with this dreaded disease.

Following closely on the heels of the great pox, Jacques de Bethencourt coined the term “venereal disease” in 1527 to describe these “maladies of Venus,” or as we now refer to them, STDs (sexually transmitted diseases).  The word “syphilis” first appears in a 1530 poem. Girolamo Fracastoro (a true romantic) waxed on about the wretched symptoms of the disease, as well as some of the early attempts at treatment. These included an herb known as “holy wood,” along with a strong dollop of mercury, which would persist as the primary syphilitic remedy well into the 20th century.
Mercury treatments came in several forms. Pills, ointments, and even luxurious mercuric steam baths were used to control the malady. The problem with mercury is it tends to be a bit poisonous. The side effects were sometimes as bad as the syphilis itself. Mercury caused its own fleet of ulcers, which typically cropped up in the mouth and throat; the patient’s teeth tended to fall out; long-term use could lead to nerve damage; and worst case scenario, the patient died of mercury poisoning. Not a great prognosis… It also gave rise to a catchy little saying:

                        “A night with Venus and a lifetime with mercury”
For a while, physicians toyed with inoculations. This process of “syphilization” was usually conducted on prostitutes, who were repeatedly dosed with “syphilis matter” (which I envision as the pustulating ooze from sores) in hopes of preventing the disease from advancing to its next stage. I wonder what the prostitutes had to say about this…

It wasn’t until 1905 that the bacterium responsible for syphilis was identified. The Wasserman blood test (I’m assuming named after some guy named Wasserman) was developed a year later. Once a diagnostic test was available, clinicians no longer had to depend on visible symptoms. This helped reduce transmission, since many carriers unknowingly spread the disease.
As if treatment with mercury wasn’t bad enough, the next remedy added arsenic to the mix. In 1910, the gifted scientist Paul Ehrlich developed Salvarsan - the first drug that actually attacked the bacterium. He tested his potent cocktail on syphilitic rabbits and knew he had struck gold when the bunnies survived. Salvarsan served as the primary treatment for syphilis. That is until our hero, Alexander Fleming, discovered penicillin in 1928.

And no syphilitic history would be complete without mentioning that most tragic of human experimentations, the Tuskegee Experiment. Begun in 1932 in Macon County, Alabama, the experiment was aimed at reducing syphilis among blacks. It was led by the Public Health Service in conjunction with the Tuskegee Institute and involved six hundred African-American males – 399 who had syphilis, 201 who did not – who were told they were being treated for “bad blood.” The men were given free medical exams and meals, but those with syphilis were never actually treated, even after penicillin was widely available. The study lasted for forty years. Along with the exams, the men were given complimentary burial insurance which, sadly, many put to good use. The last participant died on January 16th, 2004.
Few diseases have impacted society the way syphilis has, but it has also been part of some of the most groundbreaking moments in medical history. Historic records, skeletal analyses, and molecular detective work have enabled us to track the disease back in time; improvements in diagnostics have streamlined the treatment process; and the use of drugs and education have drastically reduced its incidence around the world.

So let’s hear it for syphilis! This little bug has really taught us a lot.


I'll leave you with the beautiful prose of Fracastoro...
“A shepherd once (distrust not ancient fame)
Possest these downs, and Syphilus his name.”

“He first wore Buboes dreadful to the sight.
First felt strange pains, and sleepless passed the night.
From him the malady received its name.
The neighbouring shepherds catch’d the spreading Flame”







Have a safe, syphilis-free week and I'll catch you next Friday.

Friday, February 14, 2014

The Seeds of Syphilis

Syphilis. Few words strike such fear in the hearts (and other parts) of humans. Cancer, perhaps. Leprosy, for sure. But few diseases have such an intriguing history.
My introduction to syphilis began years ago. When I was a firefighter-paramedic, infectious disease (in various forms) was rampant among the transient and drug-addicted clientele of Orlando’s west side. My tenure as a medic at a level one trauma center also gave me intimate insight into the syphilitic scourge. Ironically, retirement from the fire department brought little reprieve, for as a bioarchaeologist, I’ve come to know syphilis from a whole new perspective. Let me explain.

http://www.cdc.gov/std/syphilis/stdfact-syphilis.htmSyphilis is caused by Treponema pallidum, a little corkscrew bacterium that packs a mean punch. The common mode of transmission is via the mucous membranes of an infected person. The infection produces sores, which can also serve as portals for transmission. And don’t think the sores are the worst part, for they serve as the jumping off point of an infection trifecta.
Stage one (primary) syphilis commences with the appearance of these sores, which usually crop up at the point of infection. Keep in mind these sores can be hidden within the vagina or tucked discreetly in the anus, so just because the coast is clear, it doesn’t mean your partner is syphilis-free (CONDOMS, CONDOMS, CONDOMS!!). The bacterium is happy to hide out in the bloodstream and then appear unannounced.

Stage two, or secondary, syphilis is marked by skin rashes accompanied by “mucous membrane lesions” (think mouth, vagina, and anus). The rash can adorn various body parts, from the palms of your hands to the soles of your feet, and ranges from severe to barely noticeable. Flu-like symptoms sometimes accompany the rash. Surprisingly, stages one and two will eventually clear up, even without treatment. But without treatment, the disease can progress. Stage three can be just around the corner or lie dormant for years.


Stage three (also called tertiary) syphilis marks the point where the disease affects internal organs. Muscles may grow weak and shaky, blindness can set in, and the mind starts to go. As it progresses, organs are eroded. The heart, brain, nerves, and liver fail, but it’s the changes in the skeleton that excite bioarchaeologists, for these bony changes allow us to trace the disease back through time.

Syphilis, like any STD, initiates the blame game: no one wants to take credit for the origin of this nasty infection. This explains the plethora of names folks have conjured.
The most common was the “French Disease.” Of course, the French weren’t too fond of this term, so they referred to it as the “Neapolitan Disease,” which I’m sure infuriated the Italians. The Russians referred to it as the “Polish Disease,” and so it went, on and on…
Prior to the advent of modern medicine, differential diagnoses (distinguishing one disease from another) were haphazard, at best. Historic descriptions of syphilitics predating the 1500s could be syphilis, could be leprosy. Who knows?? The diseases produce similar symptoms, and victims were traditionally banished from all good society, so it’s difficult to tease apart their histories. To make matters worse, the Treponemal bacterium also causes other types of infections (bejel and yaws), which are spread by means other than sex. Talk about a contagion conundrum.
According to historic documents, syphilis spread rampantly throughout Europe during the 1500s – following closely on the heels of Christopher Columbus’ voyages to the New World. So perhaps it wasn’t the French, the Italians, or the Polish. Perhaps it didn’t originate in Europe at all!
There was only one way to know for sure: Bioarchaeology to the rescue!!
Syphilis leaves telltale lesions on the skeleton. It starts with small erosive wounds on the skull (“caries sicca,” in bioarc lingo), which can then spread to the nasal area. The disease eats away at the bones of the face, destroying the nose and upper palate. It also affects the lower leg bones, or tibia, causing the deposition of extra bone that gives the tibia a curved, sword-like appearance, known as “saber shin.” It’s the combination of these lesions that indicates tertiary syphilis, enabling bioarchaeologists to differentiate it from other diseases (such as leprosy, that other infamous bone destroyer).
By identifying syphilis on skeletons in archaeological contexts and radiocarbon dating these remains, we can trace its origin and diffusion across time and space. And after decades of debate, the current evidence indicates the disease was present in the Americas predating Columbus’ entry into the New World. So far, no European skeletons predating the 1500s have been proven definitively to exhibit syphilis. However, there are bioarchaeologists still combing ancient remains in Europe to confirm these findings.
According to the most recent molecular analyses (DNA), syphilis mutated from bejel or yaws during its passage from Africa, into Asia, and finally into the Americas and was present in the New World by the time Columbus landed. So Columbus not only brought tomatoes, potatoes, and corn back to Europe; his randy sailors served as the first trans-Atlantic syphilis-smugglers.
The search for syphilis is a great example of the cooperative efforts of science. By using historic documents, skeletal evidence, and confirmation via molecular analyses, the origins of this hideous disease have been traced and the debate put to rest.
At least for now...
But wait! There’s more! Tune in next week for a syphilitic sequel, as we explore the impact this nasty little bug has had through history and the many curious methods of treatment and containment.
See you next Friday, and by the way... Happy Valentine's Day!
Here's a nice article on the history and debate of syphilis. You can download the PDF.

Friday, February 7, 2014

The Debris of Life

Each of us experiences insomnia at some point in our lives. I tend to wake around 3 a.m. on a regular basis and once my brain starts churning, it usually takes me at least an hour to downshift before sleep returns.
During one of my recent 3 a.m. planning sessions, it struck me that all the plastic garbage bags I’ve ever used are stuck somewhere in a landfill, just sitting there. Think about it: every garbage bag you’ve ever stuffed, taken out, and placed on the curb is probably lying dormant amidst all the other refuse from all those other people. Very scary.

It got me thinking about the waste our bodies produce. I’m not talking about poo (since we covered that two weeks ago in Fecal Foes). I’m talking about all the other elements cast off from the living, breathing bodies we occupy.

I did a little math. Now, bear with me: math is definitely not my forte, but I kept it simple. The average human breathes about twenty times per minute (give or take a few breaths, depending on your age and size). That’s twelve hundred breaths per hour, over twenty-eight thousand per day, and over ten million each year. And that’s if you’re just sitting in the recliner, watching a hockey game (although those players tend to make me breathe a bit harder). On average we expel about 200 milliliters of CO2 per minute, 288 liters per day, and over one hundred thousand liters per year. That’s a lot of hot air.

And what about our hair? Mine’s boy-short, so it’s not a major issue, but loss is a normal part of the life cycle of our locks. About ten percent of the hair on our heads is in a “resting phase,” which means it has stopped growing and is just lying there. After a couple of months, it falls out and new hair grows in its place. We humans lose about one hundred hairs per day. That’s over three thousand per year, which may be on the low end, depending on your age and genetics. That’s a hairball at least the size of a cantaloupe.


Then, there are our nails. Nails are made of the protein keratin and are not only affected by age, but by health. Good nutrition promotes healthy nails. Poor nutrition, along with certain drugs (chemotherapy) can hamper growth and even cause nails to fall off. Fingernails grow at the rate of three millimeters a month (that’s around a tenth of an inch, for us Americans allergic to the metric system). Growth is faster when you’re young. It’s also faster if you’re pregnant. Can you image the nails on a pregnant teen?? Yikes! It’s also a scientific fact that your fingernails grow faster than your toenails. It takes about four to six months to regrow a fingernail from scratch. It’ll take you a year or so to regrow that toenail.


What about urine? According to the folks at Harvard Medical School, the average person produces about six cups of pee a day, but this is highly dependent upon how much you drink. Three or four cups of coffee in the morning will send you running to the john more frequently. Frequency also depends on the size of your bladder. A teeny-tiny person probably sports a teeny-tiny bladder. They can’t compare to say, someone in the NBA. I bet their bladders are the size of grapefruits. 

And here’s a little urinary side note: if you’re well hydrated, your urine will be a pale yellow. The darker the shade, the higher the concentration. Certain foods can alter the color. Vitamins can make it bright yellow. Carrots can turn it “sunset” orange. If you’re a regular consumer of asparagus, you know it not only tints urine a greenish hue, it also gives it a funky smell. And should you ever pee red, please see a doctor.
Ironically, urine provides a proper segue into our final topic: cells. The yellow color of our urine is due in large part to the shedding of old cells. And boy, do we shed some cells. The lifespan of a cell depends on its type. Take our blood, for instance. Red blood cells live for about four months. Not so for white blood cells. They can last for over a year. Sperm? About three days. Brain cells? A lifetime! But keep in mind those brain cells can’t be replaced if they die early. Something to think about the next time you spark a big fatty.

I’ll end with skin. Your skin accounts for about fifteen percent of your body weight and is composed of over 1.6 trillion cells. Even more amazing – you’ll lose about forty thousand of those cells each hour! That’s over a million each day! As new skin cells push their way to the surface, the ones on top die and eventually fall off (if you want to impress your friends, that dead layer is called the stratum corneum). The journey from the depths of the dermis to death on the surface takes about a month before those little skin cells flake off and flutter to the ground. In fact, take a look around your home or office. If there’s dust, there’s skin. Most of the dust that surrounds us is composed of dead skin cells, and you’ll shed about eight pounds of them each year! Fortunately, there are fish-for-hire that will take care of the problem...
Our bodies produce a lot of waste, but it’s to be expected. Each of us is composed of cells, tissues, organs, and systems, working in concert to keep us alive. And with all that productivity comes the discarded excess; the byproduct of these amazing machines. 

Think about that the next time you take out the garbage.