“Hobbit species” called into question
Many of you probably recall the news a year ago about a “new species” of human discovered in Indonesia. There was controversy then over whether it was a new species or simply a stunted human, but the debate was largely laid to rest when it was named a new species. That society was roughly 1m tall, and were thought to resemble hobbits in shape and size. Now, new studies are again calling into question this designation as a new species, claiming instead that the hobbits are actually modern humans who had their growth stunted by some unknown condition — probably microencephaly.
Homo floresiensis exhibits some differences in structure (aside from size) from modern humans, such as premolars with two roots instead of one. Once again, though, microencephaly is being claimed as the cause of the small humans rather than speciation.
Brain size also figures into this assertion, because halving the size of a human would theoretically cut brain size by only 15%. A normal human has a brain size of approximately 990cc. So a “hobbit” should have a brain that’s about 750cc. Instead, it was only 400cc — which means that the brain-size corresponds to a creature roughly the size of a meerkat. Of course, geographical isolation is often the cause of evolutionary divergence, so seeing an abnormality like this in an isolated group wouldn’t be entirely surprising. Corroborating the brain-size issue, a skull with a brain matching floresiensis’s size has been found in the vaults of London’s Royal College of Surgeons. That person had microencephaly.
As it stands now, Homo floresiensis is still its own species, and it is likely that it will remain that way until conclusive evidence pointing to its being Homo sapiens is found. Dissimilarities such as the premolar issue are genetic differences not to be lightly disregarded. Whatever your view is, expect H. floresiensis to be in the news more over the coming months and years.
British formulary for children launched
In the UK, another new reference book has been created, called the British National Formulary (BNF) for Children, designed to aid doctors prescribe for children from newborns up until the age of 18. This would be especially helpful for doctors who aren’t pediatricians who prescribe for children, who rely on their memories or sometimes outdated charts for their information. In the United States, we have doctors who diagnose a problem and then to pick a drug out of a book. This results in occasionally-funny situations at the pharmacy that often go something like this:
“I need this filled.”
“OK, Hmm.” *wanders off to pharmacist* “Hey what’s this?”
“Haha! I haven’t seen a prescription for this in fifteen years! It doesn’t exist anymore.”
This type of scenario wouldn’t happen, because the book will be kept current, with a new issue every year. (This is similar to Drug Facts and Comparisons in the US, which is updated monthly.) The guide is written by experts from Royal College of Paediatrics and Child Health, the Neonatal and Paediatric Pharmacists Group, the British Medical Association and the Royal Pharmaceutical Society of Great Britain. The guide will be made available free of charge to practitioners, and will be a companion to the BNF for adults that has been a British medical staple for years.
The creators of the publication wouldn’t be amiss in creating an electronic version of their text: updates would be easier, and as doctor’s offices progressively become more digitized, cross-referencing with a resource like BNF could be more easily integrated into sending an electronic prescription somewhere.
The dangers of repopulating too soon
Ray Nagin, the mayor of New Orleans has encouraged residents to return to their homes this week, despite warnings from Vice Admiral Allen, the officer in charge of the recovery effort. While some progress has been made in the destroyed city, most of the city’s infrastructure remains offline, or extremely flimsy. This includes hospitals, firehouses, and police stations. 40% of the city is still flooded, and many of the parts that have been drained still have mud-caked streets, which contain unknown levels of pathogens and other toxins.
Doctors warn that major disease risks remain, and Vice Admiral Allen says the city stills lacks basic services, contradicting the Mayor’s request.
“The second wave of disaster is when you welcome the people back and the infrastructure of the city is not in place,” said Dr Peter Deblieux, a casualty specialist at a New Orleans hospital.
Vice Adm Allen said the mayor’s plans to get 200,000 people back to their homes within the next 10 days were “extremely problematic”.
Ironically, this misplaced call to return comes even as some residents are still being forcibly evacuated. Tourism has been “slammed,” and many business owners who are returning to discover the state of their business are without customers, if they are even able to open at all. This begs the question: how do you rebuild a city with no commercial infrustructure? Without places to make or spend money, the city is a black hole of an economy. With most of the foodstuffs coming from the government or organizations like the Red Cross and the Salvation Army, what will residents do with their time once they return to the city? How will they rebuild if they are financially crippled, as many are? How does a city with a population without money jumpstart the wheels of economy? Government handouts? I’m not sure that would work either.
Health issues aside, the city of New Orleans is too broken to support rebuilding quite yet. The city and its people would be better off following Vice Admiral Allen’s suggestion to wait a little while longer.
The Space Cycle
A month ago to the day, I wrote about Sergei Krikalev’s record-setting time in space: 748 days. I also mentioned that it was at possible detriment to his health: being in a “zero G” environment takes its toll on the body in numerous way. Chief among them is bone density and muscle loss. The body doesn’t need the excess bone and muscle tissue to support itself in space so it gets rid of it to be more efficient. Obviously this poses some problems when you return to Earth and are unable to stand up or otherwise function normally, so astronauts on long space missions exercise to minimize the impact to their health.
Typically, they exercise on a treadmill, running with elastic suspender-like contraptions to simulate gravity in a crude way. Now a new device, called the Space Cycle, being developed at UC Irvine utilizes artificial gravity through centrifugal forces. The device scales from 1G to 5Gs, and allows two people to exercise on it simultaneously. One on an elliptical machine or bike, and the other doing a sort of squat. The one pedalling causes the cetrifuge to spin (video).
It’s a cool idea, though looking at the video leads me to believe that unless the device is shrunk somewhat, it’ll be too large to fit inside current space quarters. Honestly, I’m not sure how much more it could be reduced, but its radius seems too great to store easily. Another problem with the cycle is that in “zero gravity,” any spinning object can cause torque on the vessel as well, so a way of counteracting this torque will have to be developed.
In any case, it’s nice to see some progress being made towards allowing astronauts and cosmonauts to stay in space for extended periods of time. Along the same vein, I mention in the writeup that I wondered about drugs like Fosamax and other bisphosphonates being used to prevent bone loss. Dr. Jay Buckey, a doctor at Dartmouth Medical School returned my email, stating that while such drugs had been investigated in bed rest studies (physiological analogs), they are not actually utilized, and that several people in space have reduced their bone density loss to minimal levels simply by exercising.
The human brain is still evolving
Scientists have discovered that the human brain is still evolving. By comparing modern man to his ancestors of 37,000 years ago — a blink of the eye in evolutionary timescales — researchers have discovered two genes linked to brain size. One of the new genes emerged only 5,800(!) years ago, and is only present in 30% of human beings. These very short timeframes suggest intense selection pressures.
What’s more interesting is that these two gene variants arose right around the time that cultural behavior developed. It appeared alongside other things like art, music, and sophisticated religious practices and tools.
The researchers caution that the two genes are linked to increased brain size, but not necessarily greater intelligence. I would speculate that they are but a small piece in the evolving of the modern human brain. Consider that Neanderthals were better physically suited to a harsh environment, but that Homo sapiens outlasted Neanderthals and became the dominant species on Earth. Neanderthals had no speech or written language, whereas their bigger-brained Homo sapiens cousins did. Perhaps these two genes are but one part of a larger evolutionary picture that we are just now discovering.
I have written in the past about the difference between genes and memes, and the human social structure. It is thought that these evolutionary changes conferred to us some greater ability to survive (such is the nature of natural selection). But natural selection doesn’t have to be limited to purely physical pressures. Societal pressures can nudge natural selection along a given path by allowing those with greater societal savvy (for lack of a better term) to procreate more. As humans became more community based and interdependent on one another, the ability to interact socially as a means of reproducing becomes valuable. In essence, genes serve the overarching meme, which is complex interdependence and economics.
The most exciting aspect of this discovery is that it means that the human brain is still evolving today, and that humans a long time from now will probably have different brains and capabilities than we do today.
Of course, the real question everyone wants to know the answer to is… How long before we can beat a cashier senseless so we can steal a candy bar… without lifting a finger?
Bullets: sleepwalking, sleepy interns, and geriatric distractibility
More bullets!
- Apparently there’s a myth that says that you shouldn’t wake a sleepwalker because they might have a heart attack if you do. This sounds a little ridiculous to me simply because heart attacks don’t just magically happen, they usually have an underlying cause, and being woken isn’t enough of a stressor to be one of them. (When was the last time you heard of a person dropping dead from being badly startled?) Research confirms this. For some reason, I think you’re more likely to have a heart attack after being woken by a shrieking cell phone more than anything else: night time somnambulation included. Maybe it’s just me, though.
- Medical interns (med students) are tired a lot, often because they’re putting in lots of hours without really doing anything useful, whether its learning or helping. Yaz says the hours he puts in in a hospital are a good time to learn in a relatively risk-free environment. Who’s right? I guess it depends on who you ask and what kind of person they are. How many of your fellow students feel the same way you do about this, Yaz?
- Elderly people’s mental faculties are generally not what they were when they were younger, but research shows that it’s not because they’re becoming less intelligent, it’s because they’re more distracted. But this can be reversed. I would also say that their effective cognitive ability decreases also because they doubt themselves. Ever watched an elderly person operate a piece of technology? You can generally show them 100 times, but they’re still ask the same questions: I think it has to do with lack of confidence. I’d like to see some research on the effect of repetitive hand-holding.
Aside from my next post (which will be my last for the day), I’m going to try to keep current on the science news going on, opting instead to forgo posting something if I can’t get to it within 24 hours of its announcement. Unless it’s a press release about new research or something like that.
The problem of antibiotic resistance
I’ve had this article written for about two weeks now, and I’ve been holding onto it for a short time, but I’m not sure why. So here it is.
I cover the basics of antibiotics, how they work, why viruses and bacteria are different, why antiobiotic resistance is such a big problem, how it’s being dealt with by doctors and the pharmaceutical industry, and why this is relevant to you.
In the real world, even if a patient knows all these things when the see their doctors, it doesn’t necessarily help when they demand something that will make them feel better. Doctors have long felt the pressure to write prescriptions for antibiotics when the cause of the ailment is likely viral. This keeps the patients happy, but it is causing problems for the reasons I outlined above. Doctors know they’re digging a pharmaceutical hole by giving in to patient demands, but often appeasement is easier than sending a patient home unhappy without a prescription.
Come inside and check it out. Maybe you’ll reconsider asking for a prescription the next time you visit your doctor…