Complex Bird Calls

Sitting in the outdoor tub with the stillness of night stealing in, I love to listen to the evening bird calls, as each species takes its turn, before flying off to the night's roost. I can almost predict the sequence of calls, as the titmice and goldfinches begin the evening's sign-off, followed by a tumultuous Carolina wren. Then the wood thrush and the cardinal vie to see which one closes off the day's symphony, before the whippoorwill ushers in the night chorus.

I love to listen carefully to the various calls, trying to discern if birds of different species seem inclined to listen to each other—if only to determine when their own song can be offered by slipping it in between the calls of others, so as to minimize the overlap and maximize the chance that each of them will be heard. The intent of their singing is not to compete with a different species, but to signal any nearby birds of its own species that it's here and deserves respect. (In a similar fashion, it has been shown that birds singing in cities modify their calls, in an attempt to be heard above the din.)

Most of the calls I recognize come from old friends, with whom we've cohabited in this clearing in the woods for a few decades now. I have come to expect their voices each evening. But now and then I hear an unfamiliar call and wonder who it is. Might it be a visitor who's testing whether it might find a home here? Might it just be passing through and stopping on a pleasant evening, to join the chorus?

This particular evening brings a new, rather complex call. It seems to me that it's two different birds—one shouting out a high-pitched melodious squawk, sort of like a soprano bluebird. The second call is a lower-pitched “burp, burp, burp.” It must be two different species, I think, with such contrasting calls. They even seem to be coming from two different directions in the woods.

But as I listen over several minutes, I begin to become suspicious about my first impression. These two different calls are precisely synchronized. They quickly follow one another in the same succession, but never overlap. When I normally listen to two different species of birds calling out, they seem to be trying to fit their calls into each other's gaps, but inevitably get a little sloppy and overlap each other just a bit. These two calls tonight never overlapped.

So maybe I'm listening to just one bird that sings out with two very different calls—one a high-pitched squeal and the other a low-pitched burp? That could be. The wood thrush has a three-part call—each part having a very different quality. And I've written here before how the different parts of the wood thrush's call even seem to emanate from different locations in the woods. I have decided that the wood thrush's song appears to come from different directions, because one part of the call reflects off trees leaves, while the other part penetrates deep into the woods.

So what am I listening to this evening—two birds who have an uncanny ability to perfectly synchronize their calls, or a single bird with a two-part call? I do seem to hear the call coming from two different locations in the woods. The answer will not come tonight, as the calls soon ceased. The bird (or birds) will hold onto their secret for another day.

The Sun

There will be a solar eclipse in the US on August 21, and I will be (hopefully) in a good place to observe it. For practice I bought a solar filter to place over my camera lens, to take photos of the sun. The first photo above is from NASA, of a solar flare a few years ago. One must wait until the moment when a flare occurs, to catch it. The bottom two photos I took recently through my filter. On the bottom photo I seem to have some internal reflections inside the lens. Maybe I can figure out a way to get rid of them for next month's extravaganza. Click to enlarge.

Smart Machines—Part 2

Something similar has happened in the field of embodied cognition. People have built robots for a long time, and some of them—especially when they look like a human and sort of act like one—have been very impressive. But again, these robots could do only what their designers had programmed their “brains” to do. 

What was frustrating and limiting was that every action the robot did required enormous computing power—yet those actions were quite simple. If the robot encountered something the scientists had not thought to include in its software, the robot would spectacularly fail. Maybe its designers had cleverly (and very complexly) programmed the robot to walk upstairs, but if it stepped on a marble, it'd tumble over and lie incapacitated. And any robot that accomplished impressive feats required such brainpower that it gulped large quantities of energy and drained its batteries quickly. (Our human brain is an energy hog.)

When researchers realized the finesse, efficiency, and proficiency of EC and began to build robots based on this principle, those robots are taking the next quantum leap into the future. The EC principle allowed them to create robots that move uncannily like humans and other animals, without much computer power and without the need for the robot's “brain” to plan and execute every move.

To watch a video of a robot programmed with EC is rather astonishing—if not also a little eerie. (This link gives you a number of such videos: https://www.youtube.com/user/BostonDynamics). Boston Dynamics has built several of them and has demonstrated how capable and autonomous they are. Take one of these robots outdoors, where it encounters terrain that it's never negotiated before—uneven ground, snow and ice, deep mud—and it does better than a human can. You watch one of the robot's feet slip or get bogged down, and it stumbles, awkwardly pirouettes, but quickly recovers. Another video shows a human researcher sneaking up behind a robot and giving it a violent shove with a stick. The robot stumbles forward, catches its balance, and continues its previous activity.

These amazing accomplishments have researchers very excited and furiously engaged in experiments to improve what these smart machines can do. The future in the fields of AI and EC is nearly upon us. What comes next? What novel accomplishments will we soon see? The promises are both thrilling and sobering—even rather ominous.

For example, what happens when the cognitive abilities of an AI computer exceed those of the human brain? It's only a matter of time. They have already demonstrated the ability to best humans in a few kinds of intelligence tests, but yet still fall quite short of the human brain's overall flexible abilities. That threshold will soon be crossed, however. When it happens, will an AI computer then be able to reason, become self-aware, or even possess consciousness?

These questions interfere with the sleep of some scientists and philosophers. They are worrisome to many people. A few people even fear that computers might take over the world and force us feeble humans to be their slaves. This fear has spawned a few fascinating books and movies. Nobody knows what will happen. What is disconcerting, at the least, is that research is moving quickly forward, with little consideration of where we are going or what precautions should be made. (That's an old story with human technology.)

Something similar might be said about EC robots. Most of the current research in this area is being sponsored by the military. What are their plans for these smart machines? Obviously, these robots will someday perform much more effectively on the battlefield than human soldiers—being stronger, faster, and more invincible. The death of a robot—no matter its price—is far less onerous than the death of a soldier. But what might happen when a platoon of EC robots invades what is believed to be a fortified bunker of enemy soldiers, and finds it instead occupied by a group of cowering women and children? Will these smart machines also have the moral sense to halt their invasion?

Both AI and EC robots promise some wonderful benefits. But like so much technology of the past, what was once seen as a blessing sometimes had a dark side. Are we being careful enough?

Smart Machines—Part 1

There are some amazing advances currently being made in two related scientific fields—both of which are exploring ways to create machines that mimic (and even surpass) human cognitive and physical capabilities. In each area researchers have built robots that exhibit stunning skills. Engineers and scientists have tried for several decades to manufacture robots and computers that are as proficient as human beings, with very little success. In the last few years breakthroughs have occurred.

The two similar fields are artificial intelligence (AI) and embodied cognition (EC). The holy grail for many years in AI has been to create a computer that has cognitive abilities equal to that of the human mind. Computers can process data far faster than the human brain can, but the problem has been figuring out how to program a computer to be able to preform the nimble, parallel processing that the brain does; which allows it to instantly recognize faces, or exhibit impressive learning capabilities. That problem is now being solved.

The second smart machine accomplishment has seen the construction of robots that feature embodied cognition. This breakthrough had to wait until scientists could fully appreciate what EC is. In humans (and most animals) most of the things that we do—walk, breathe, swim, or just move the body—are accomplished without any conscious effort on our part.

Do you consciously think and guide your body through every move, when you walk into the kitchen to get a drink of water? What is required to do so is a long and complex string of interacting movements and nerve signals that pretty much do the job on their own. Otherwise, we'd literally be moving in ultra-slow motion, unable to accomplish but one or two activities in a day's time. What allows us to do so many things and to do them fluidly and quickly is EC—wherein the major part of our brain unconsciously engages in myriad activities, so as to free up our thinking brain to ponder more esoteric things like yesterday's events and planning tomorrow's.

The recent AI computers use what is referred to as “deep learning,” where the computer teaches itself. Earlier attempts at AI used the capabilities of super computers to make lightning-fast computations using incredibly complex software programs, but these machines could only do what the human programmers decided to program into them. If the AI computer encountered a novel situation, it was stumped, because nobody had thought to program that particular scenario.

The algorithms being used in the latest AI computers are far less complex (because they do not need to cover every scenario imaginable), but are fundamentally more flexible—like the human brain. The computer teaches itself. Give it the simple rules of chess or Go or Jeopardy!, and it will teach itself by running millions of practice sessions. It even invents novel moves in these games that a human had never thought of. World champions of these three games have recently been humiliated by AI machines.

More smart machines next time...

Black and White Moth

Click to enlarge.

Mini Mandible

I have endured a life of dental infirmity. There's not a tooth in my head that has escaped the attention of various dentists, due to decay or many other problems. Had I been born a few decades earlier, the majority of my current teeth would have been replaced by something artificial: so-called false teeth. Most elders in my family had them. I remember my grandfather spooking me as a young kid by bulging out his cheeks and then seemingly regurgitating a whole mouthful of dentures at me.

My dental dilemmas have been due to three unfortunate circumstances: bad genes, bad food, and bad birth timing. My genes may have endowed me with good resistance to many common diseases, but they have led to innumerable teeth fillings, gum infections, and those incredibly costly devises: dental bridges. My generation—adolescence in the 1950s—had far too much access to sugar and its insidious invasion of tooth enamel. Finally, my timing was bad—my kids benefited from fluoride in their drinking water, something not yet available in my youth. Although they inherited my defective dental genes, their cavities have been few.

There is another problem with my mouth (although some people would say it's not just a dental issue): my lower front teeth are as crooked as a drunk's path laid down, as he wanders from a bar after midnight, struggling to find his way home. Those bottom teeth are staggered and overlapped, as each of them contends for a paucity of space. To aggravate the situation, my upper row of front teeth do not squarely meet the lower jaw's row, but hangs over them, like an ivory awning. My dental problems have been expensive and at times painful, but I know I could have had far more troublesome health concerns, so I live with it.

It can help to discover the cause of chronic health problems—if only to understand them, even though you can do little to change the situation. An example that helps me to understand my dental predicaments was recently finding out about the results of research that has examined the cause of some of my dental struggles.

Researchers at the University of Arkansas write about the amazing capabilities of our teeth. (Even though I have my problems with them, it helps to be reminded of how well they do their job.) They point out that, while our teeth do so well at breaking up food, we appear to have too many of them—as if they are too big for our mouth. Our teeth are overly crowded and uneven, and we often get impacted wisdom teeth. Overbites are common. (That's me!)

What's going on? It's not that our teeth are too big, the researchers say, but that our jaw is too small. They point out that, while the size and shape of our teeth are genetically programmed by evolution (and thus cannot change, as we age), our jaw can respond to environmental conditions and grow. The more we chew tough food, the greater the strain on our jawbone, which responds by growing!

Our deep ancestors had to munch some pretty tough food, so their jaws grew accordingly. As a result, our hunter-gatherer ancestors had perfectly aligned teeth. This is also true for most animals. Even our current human cousins who live a primitive lifestyle possess jaws and teeth that match. Modern humans consume soft mush at tender ages, so their jaws—unchallenged by stress—become stunted. Teeth get jammed. Dentists are beginning to focus on helping kids to grow larger jaws, rather than use expensive orthodontics. Even adults can get surgery to lengthen their jaws.

Maybe a larger jaw would have fended off some of my dental problems? It could also have given me a more handsome countenance—giving me that desirable square jaw. It could have paved the way for fame in Hollywood, where a movie star's salary could easily cover any dental issue I've ever faced. But at least I'm not frightening my grandkids by blowing out my false teeth at them.

Milky Driveway

An Earth globe in the foreground and Moon globe in the distance, photographed in my driveway. Maybe I'll call it my personal Milky Way driveway? Click to enlarge.