Brouhaha Brewing—Part 1

Physicists in recent years have been confronted with a number of intractable problems that just keep mocking their attempts to resolve them. Some of the brightest researchers (count Albert Einstein and Stephen Hawking among them) have unsuccessfully banged their heads against a brick wall of seemingly insoluble problems for much of their careers.

Here are a few examples: Why can't scientists get Einstein's theory of relativity and quantum mechanics to agree? What the hell is all the mysterious “dark matter” and “dark energy” that constitutes some 96% of the universe, and why can't we find it? Why can't a single unified theory describing and relating all the fundamental forces of the universe be found? How can the confusing soup of fundamental particles be sorted out and finalized? Why is it that string theory—which appears to be an elegant “theory of everything”—started out so promising a few decades ago, but has gotten bogged down in the last few years, such that all attempts to resolve it have either led to a dead end or even more puzzling mysteries? What is the nature of the bizarre mechanism that causes “quantum entanglement,” in which information seems to travel faster than light—in fact, instantaneously? (That last one really bugged Einstein.)

Now comes a mathematician who claims to have solved all these quandaries (and more) by taking a completely new approach. His theory, which he's dubbed “Geometric Unity,” is a work that he's devoted his last 20 years to developing. This remarkable announcement has been issued by one Eric Weinstein. He has a PhD in mathematical physics, but dropped out of academia 20 years ago to pursue his dream as a lone wolf.

It's both a startling and a romantic story: an unknown genius toiling away for two decades in the shadows, eclipsing what legions of physicists and mathematicians have failed to do for a couple of generations. Weinstein was invited this past May to give a lecture at Oxford University, to describe his theory and its implications. He says there is no missing dark matter in his calculations; it's all present and accounted for. His model is apparently straightforward and elegant, and it makes many new predictions about particle physics.

This is an amazing development—one fit for sensational press headlines; and it's gotten a few, though the topic is a bit too complicated for your typical tabloid sound bite shrieks. Has Dr. Weinstein truly made the work of countless scientists futile? Some non-scientists may jump on this announcement and get carried away with its implications, but let's hold on a minute here.

This situation is reminiscent of the sensational news a year or so ago, that Italian experimentalists had measured neutrinos exceeding the speed of light. Gracious! Einstein was wrong! The speed of light is not an absolute limit, after all! What furious sound-bite reporting zinged around the world's cyber lanes at the time! A few months later, however, further investigation showed that they had made an experimental error. So Einstein was right after all! I doubt that even one of all those newspapers and TV “news” shows—those that had earlier trumpeted the amazing “discovery”—even noticed the retraction. If they did, they'd certainly not regard it as news worthy.

More on the brouhaha next time...

Tree Cricket on Sedum

Ckick to enlarge

Our Denisovan Cousins

The July issue of National Geographic Magazine describes an amazing story of the recent discovery of yet another species of our human family that went extinct tens of thousands of years ago: the Denisovans. Remarkably similar to the Neanderthals, the Denisovans were a human subspecies that left Africa long before our species Homo sapiens did. They spread fairly widely throughout Eurasia and then died out. And, like the Neanderthals, they left traces of their DNA in us modern humans. In other words, our human ancestors seemed to be attracted enough by these extinct cousins of ours to have interbred with them, which finds us continuing to carry around a little of their DNA.

I find the story of human evolution fascinating. The narrative has been spectacularly amplified in recent years through evermore precise genetic measurement tools. Where anthropologists were once confined to detailed examination of the shape and appearance of fossil skeletal remains, they now can perform exacting genetic analyses of the tiniest of bone fragments.

Before 2008 we were completely unaware that a subspecies like the Denisovans even existed. Their population appears to have been rather small and no identifiable bone fragments had ever been found. Then, five years ago, digging in a cave that had repeatedly been used by people over the eons, a Russian archeologist discovered a miniscule bone fragment in a Siberian cave called Denisova. Had the discovery been made just a few years earlier, it is unlikely that this wee fragment would ever had led to the realization that it was from a previously unknown prehistoric species of human. 

Cutting-edge DNA analytical methods that have recently been developed in Germany (Max Planck Institute) were able to construct the complete genome of the person from whom the bone fragment came: the left pinky finger of an eight-year-old girl. (They even got a pretty good idea of the color of her hair!) In fact, these techniques have become so precise that the girl's genome could be probed to the extent that researchers could even describe the different genetic contributions she received from her father and mother. From a bone piece the size of a dried bean!

The speed with which our evolutionary history is being filled out is astounding. Scientists are discovering that our origin is far more complex and rich than we'd ever have guessed. Anthropology is as exciting a field as cosmology these days, as the rate of new discoveries is so great that specialists in these fields have a hard time keeping up—let alone us average beings.

It makes me wonder about the even better research tools that will very soon become available, and the wonderful stories that they will reveal about the nature and origins of our universe and all its marvels. I am getting perilously close to my 73^rd birthday, which causes me to increasingly reflect upon my mortality and how little time I have left to learn about all these neat things. At my age I take great comfort in knowing that the pace of discovery has picked up as much as it has. Hasten on, science!

Scared Duck

A ground spider squats next to my tub duckie, apparently causing quite a fright.

Fading Thrushes

I have written before (“Wood Thrush Encounters,” 7/19/08 and “Foreign Bird Call,” 10/31/12) of how thrilled I get when the wood thrush sings out from the forest. Most species of thrush have beautiful songs, and of the handful of thrush varieties we are blessed with around here, the wood thrush is clearly the winner. Its call is melodic, inventive, artistic, and exquisite—like a Bach étude.

The bad news is that wood thrushes are on a steep decline. Their habitat—both in the summer in the US and over the winter in Central America—is dwindling, along with their population. I am keenly aware, as their gorgeous songs become scarcer in our woods, that the days we may listen to their melodies are limited.

Maybe the dwindling process is even going on very locally now. The last couple of years we have heard their calls much less often. We once were regularly regaled in early morning and after sunset with their repeated songs—never once tiring of them. Now we seldom hear them. I caught the old familiar call a few nights ago, for the first time in weeks. How it thrilled me! I stopped in my tracks and gratefully tuned in.

I wonder what will happen on the nature scene, after the wood thrush is gone—as seems rather inevitable. For a few million years the bird has filled its niche—fulfilling many more functions than simply singing for human pleasure. How will its disappearance upset the exquisitely balanced ecosystem? It will leave a hole—one that undoubtedly will be filled by an opportunist, who I'm sure will not be able to sing nearly as beautifully.

Nature, over the eons, has attained a robust yet fragile equilibrium; a sacred stability that we only barely understand. In the process, a divine natural art has been created. We blundering humans are defacing that scared art—for no good reason. We will wake up someday and face the results of our devastation—but how much will we have permanently lost by then?

Darth Vader Sawfly

Dove Nest

We were treated this spring (May and June) with a mourning dove nest built near the house, rather close to the ground, in a small tree. We first noticed the nest when we walked under the tree and flushed a dove, who noisily flew away. This event occurred a few more times, which caused us to look closer and to spot the nest.

The nest of the mourning dove is a simple, flimsy-looking flat platform. It is not lined with any soft material, as are other birds' nests, nor is it in the shape of a cozy little cup that secures the chicks. It's easy to look right through the nest and miss it, until the bird's repeated fleeing begins to attract your attention. My wife then spotted two white eggs and we knew that we might be in for a treat, as the babies later hatched and then were fed.

Doves are monogamous—at least through one breeding season, and sometimes for subsequent seasons. They can live as long as 20 years in captivity, though their lifespan in the wild is far shorter. They may raise several broods in one season. The male selects the nesting site and carries construction materials to the future mom, who then builds the nest. Unlike other birds, who carefully fashion a nest over several days, the mourning dove seems to have other priorities—since the flimsy nest we saw seems to have been hastily constructed.

The mourning dove broods and tends to the hatchlings longer than most songbirds. The time span from egg laying to fledging may be well over a month, rather than just a few weeks, as for, example, the wren.

Our doves laid their two eggs early in chilly May. The fact that we scared the parent away so often on those cold days had me concerned that the eggs had gotten chilled and the embryos died. Yet, day after day, the parent sat there—less and less inclined to flee, as it became habituated to us. (I learned later that we were probably watching dad brood, since he usually takes the day shift, leaving mom to cover the nights.)

But one day I thought I saw a baby's head peeking out from under the parent. Grabbing my camera and zooming in for a shot, I soon saw the second head pop out from under dad's wing. We doubled up on our nest watching—eager to watch the little ones grow. It's amazing how fast a chick develops from a feeble, downy lump into a bird virtually as large and full-feathered as its parent, in just a week or so.

Doves are strictly vegetarian—its diet consisting of seeds and fruit. They have a large crop in their chest, into which they stuff a capacious amount of seed, which later gets ground into edible mush. After the chicks hatch, the crop-stuffed parent flies to the nest to feed the babies. Whereas most songbirds bring an insect that gets stuffed into a chick's gaping maw, the dove chick jams its head down the throat of its parent, causing it to regurgitate what's called “crop milk,” rich in proteins and fat.

We never saw the feeding activity, but we kept a close watch over the next week or two, noting the chicks grow ever larger—wondering how that flimsy nest could possibly support two big chicks and a parent. Were we seeing a great balancing act, or was the fragile-looking nest far stronger than it appeared? Later research told me that the nest may get used again—maybe even in the next year. I'm beginning to think that momma doves are very savvy structural engineers, who build robust yet delicate nests.

One day in June the chicks fledged. On our morning nest inspection that day all that greeted us was an “empty nest.” For the next couple of days we saw two doves clumsily flee, as we walked near the tree. A little research told me that the fledglings may hang around their nest area for a few days. Now we will eagerly survey the nest, hoping soon to spot a couple more eggs sitting in the minimalist nest, starting another brood.