Tuesday, 31 May 2011

The Hors D’Oeuvres at Westminster A-Bee

            As many a six-year-old aspiring princess will tell you, there are many roads to royalty. One can, for example, marry a prince (aka the Kate Middleton route), overthrow an existing monarch by force and declare oneself royal ruler (slightly bloodier), or be sure to finish one’s evening jelly? If you happen to be a honeybee, the latter is definitely the way to go. It turns out that hive royals are not selected through democratic election, military coups, or even heredity succession. Instead, the lucky larva that ends up as hive queen is singled out by her brand of baby food.

            We all learned in high school biology that our height, eye colour, ear-lobe type, and potato chip preference are determined by our DNA. That is to say that the random tango of our parent’s chromosomes pre-determines the basic physiology of the being that starts to develop when sperm meets egg. So queen bees (which develop faster, live longer, and are much bigger than their worker bee counterparts) must have the blue-blooded genes to match, right? Wrong! In true rags to riches form, queen bees are as plain-jane as they come when they hatch. It’s their princely diet that allows them to ascend beyond their worker bee sisters.

            The genetics of a honeybee hive are both complex and highly scandalous to their WASP neighbours. In short, the queen and all of the worker bees are female, and each have 32 chromosomes. Males (or drones) have half as many chromosomes and basically live to mate, producing thousands of genetically identical sperm cells. The queen mates with several drones to produce a slew of daughter worker bees. These have in common with each other the same proportion of maternal DNA as humans do with our siblings. The difference between us and our fine furry flying friends is that all of the sperm from a single drone is identical, meaning that offspring from the same father are genetically closer than human sisters. The research community has not offered any insight into whether this means they had better slumber parties.

So what do the genes of a queen bee look like? Just like those of all her worker bee sisters. Although the female bees in a hive are not genetically identical, they are all sisters (or half sisters) and have similar diversity to that in a blended modern family. What gives the queen her very distinctive physical features and lifestyle is therefore not her DNA, but rather the way in which her body develops. In other words: in the honeybee world the “nature vs. nurture” debate is truly a no-contest.

            In the larval stage, baby bees are tended to by their worker bee sisters. When the hive needs a new queen so the old queen can die or move out colonial-style to build a new hive and expand the empire, the workers feed select larvae “royal jelly.” This exclusive confection is produced by glands on their heads and contains a compound called royalactin. In dramatic magic potion fashion, this compound induces a plethora of physiological responses ultimately resulting in a new melliferal monarch.

            Although Lady Gaga might disagree, if you ask a queen bee what makes her so fabulous she will most certainly not reply, “I was born this way!”

Thursday, 19 May 2011

Real Guinea Pigs don't Giggle

Reading the titles of the scientific articles published in any given week ultimately leaves me with one take-home message: scientists will study anything. Case in point: right now the Humour Research Lab (HuRL) in Boulder Colorado is investigating whether things are funnier under the influence of marijuana. Funny, eh?

            But seriously folks, humour is a gravely important topic highly deserving of a dedicated and meticulous team of scrupulously unfunny real scientist researchers. Really. Okay, the lucky grad students performing this work are allowed to be a little funny, but the results of their work (however amusing to the general public) are crucial pieces of the human psychology puzzle. As these researchers will point out (to any bench scientist pointing and laughing at them) the ubiquity and pervasiveness of humour in human culture indicates a key role in psychological well-being. Anxiousness, fear, and especially happiness have been hot topics in the modern world of psychological research. Studies about the nature of humour add to this body of work by contributing valuable insight into how humans interpret and process incoming information.

            So exactly how are these studies conducted? Do these researchers just wander around with clip boards occasionally noting down “funny” or “not funny,” or are test subjects shoved into an MRI and forced to watch Fresh Prince reruns until their patronizing amusement centres light up? Perhaps surprisingly, the truth is closer to the first scenario with a few laughable modifications. Students from a university campus were recruited to participate in studies with the promise of either course credit or candy bars (that’s right, undergraduates can be bought with candy). To earn their sugary snack, students were asked to read descriptions of various scenarios and respond to questions regarding how they felt about them. I can only imagine that reporting these results in a respectable fashion takes more than a dash of academic discipline as the questionnaires tend to include such sitcom gold as a man rubbing his bare genitalia on a willing kitten, someone making the decision to snort the ashes of their deceased father, and a man having sex with a dead chicken before cooking it for dinner. The final academic publication walks a fine line between rigorous science and reading material for future humour test subjects.

            When all of the giggling dies down, what are we learning about all of this funny business? The hypothesis championed by the folks in Boulder is termed “benign violation.” By this theory, things are funny when they challenge or disrupt a cultural norm (that’s the “violation” part), and are seen as harmless or “benign.” This theory explains why a child hitting his father in the crotch with a baseball bat is endlessly hilarious (just ask Bob Sagget), but only until the injury requires surgery stopping the man from having more children (suddenly a little more serious). According to this group, we find disturbing, disgusting, and generally wrong things absolutely uproarious, unless they present a real threat to our well-being or that of those we identify with.

            So the next time that you’re chuckling over some stooge-worthy antics, remember that your mom was right: “it’s all fun and games until…”

Read more in HuRL's benign violation paper

Tuesday, 10 May 2011

Eat Your Heart Out Noah: Ants on the High Seas

What do you get when you mix a colony of fire ants, a pool of water and biological engineers? Science! More specifically, you get ant behavior that starts to blur the lines between animal psychology and grade 12 physics.

            We’ve all seen footage of a colony of ants cooperating to move food or construction materials: each ant lending a mandible as one small cog in the colony machine. This metaphor starts to become a little less metaphorical, however, when the construction materials in question are the ants themselves. When they’re not breaking up picnics, it turns out that ants can also build self-assembling rafts with astonishing characteristics.

In a paper published in the May 10th, 2011 edition of the Proceedings of the National Academy of Sciences, a group of engineers and biologists explore the physical dynamics of these bug barges. They collected road-side fire ant colonies, made ant-balls by stirring several thousand ants around in a beaker, and finally poured the insect orbs into tanks of water to observe the effects.What these researchers saw was not panicked dog-paddling and tiny wails of “every ant for themselves!” but rather the colony weaving together to form a waterproof mesh that can float for days, or even weeks. Looking at the microscopic structure of the rafts revealed that the ants both “hold hands” and (gently) grasp other’s limbs in their mandibles to hold the structure together. The ant-raft also responds to such stimuli as being poked with a stick by grasping each other more tightly to form a finer and more waterproof netting.

Yes, I know what you’re thinking: insects floating are not exactly news. Insect exoskeletons are slightly hydrophobic (repel water) and we’ve all seen insects poised delicately on a pond’s surface on a calm day. While it might be underwhelming that the ant rafts are both waterproof and buoyant, the shape and physical dynamics of the raft structure definitely fall into the amazing category. In fact, when forming such floating vessels, individual ants behave less like independent creatures and more like particles in a liquid. The rafts in these experiments were constructed from thousands of ants in a rough ball shape. When placed on the surface of the water, the ants spread out in a matter of minutes to form a pancake-shaped floating raft (picture a ball of silly putty left on a counter in a warm kitchen for a couple of days). In fact, the physical properties of the ant masses were found to be more similar to a physical substance than a conglomeration of multiple sentient beings.

The self-assembling, self-healing, and impressive physical characteristics of the ant rafts in this study have attractive implications for the application of nanorobotics in similar tasks. Once again, Nature’s astounding engineering projects leave our biomimetic scientific efforts scrambling to keep up.

Learn more in this incredible ant raft research paper.
Also check out the amazing video footage

Wednesday, 4 May 2011

Feed a Fever, Fatten a Heart Attack?

“A diet low in saturated fats,” is a phrase we most often associate with a healthy, heart-happy lifestyle. If your dad came home from the hospital after a heart attack, a cheeseburger likely wouldn’t be the first object you’d thrust into his hand. And while I’m not suggesting you put a poutine vending machine in your local cardiac ward, new research suggests that saturated fats might actually be beneficial for heart patients.

            A new study headed by Margaret Chandler of Case Western Reserve University investigated the effect of a high-fat diet on rats with heart failure. Surprisingly (at least to this health-conscious citizen), the post-heart attack rats fed on a high fat diet had improved heart function over their ho-hum diet counterparts. This was true for resting rats and (rat race anyone?) rats under stress.

            So how on earth does a high fat diet HELP heart function? The same group of researchers tried to answer this question by investigating what genes are being expressed in the healthy, heart-unhappy, and fat-fed rats. This is like looking at which tools from an industrial-sized toolbox are out on the bench, and which are stored away. Using this metaphor, heart cells in a person who has heart damage might put away their hammer and take out their sledge hammer. However, this new study shows that a high fat diet actually helps to make damaged heart use more of the same tools as a healthy heart, thus bringing it closer to a pre-heart attack state.

            Now to burst your bubble, before you go stock up on fast-food coupons: diets high in saturated fat do nothing (read NOTHING) to help a normal healthy heart. And as a crucial caution for all new research with a medical slant: Don’t Try This at Home!

            This type of study might someday lead to better treatment to help keep heart patients healthy. In the mean time it’s a pretty cool study that makes this scientist go, “Huh, who knew?”