Why do birds sing?

Those who study bird vocalisations have distinguished different types of bird sounds, to call and communicate to other birds such things as territorial demarcation, sexual status and availability for mating, alarm, and perhaps other things too such as the discovery of a food source etc... the things you would expect any basic form of communication to express.

But the apparently random and spontaneous songs they sing remain largely a mystery. As charming and joyful as these songs often are, I would suggest that they are actually serving a very particular purpose, and indeed a vital one that is at once more profound, sophisticated, and rich than anyone previously ever imagined.

Whilst sitting in the garden one day I heard the song of the Black bird in a nearby tree. And I began to wonder at the meaning of this song, as many have before.
The first thing I considered is that the Blackbird always sings at the beginning of the day as the sun is coming up, and again at the end of the day, at sunset. Always the first bird to sing, and the last of the day.
Observing it for some time, I noticed that it invariably chooses the most prominent position at the very top of the tallest tree, with a largely unobstructed surrounding view of the local environment. As it sings, it turns it's head with small movements and slight adjustments of posture and position, directing it's song in the various directions for all to hear... What could this mean?

Clearly by taking such a prominent and unobstructed position with the broadest scope, the broadcast of the sound is given maximum range, both to send out the song... but also to hear it return.

Could this be a form of echo-location?

Is the bird actually mapping the environment with song?

We know that sharks, whales and fish in the sea employ such methods to define their environment.
Sharks to locate and sense prey over great distances, fish, to elude them, and whales are known to use the thermal currents as channels for their song to be carried sometimes for miles.

It stands to reason that birds should employ these means also.
Like the marine life mentioned, they are entirely dependent on the fluid environment they live in... in this instance, the air.
Flight requires an accurate and dependable knowledge of the terrain and potential obstacles likely to be encountered in a rapidly changing environment, as birds cut quickly through the air. While evolution has promoted a heightened visual acuity in order to meet this demand in part... it cannot account for the unseen obstacles that may lie in wait behind large structures, or objects appearing suddenly from behind trees and buildings etc. For which the bird, moving rapidly through the air could not have time to compensate for if it were to fly around a corner and encounter this obstacle or obstacles.
I think it must therefore benefit the bird to know in advance just what lies in wait... with the visual sense only employed in a secondary capacity for flight... surely the incredibly slow process of evolution which has modelled the bird for flight, and all the tools required for this manner of life would also have given rise to such an ability.

I think the way this works would be that the song, which is a complex system of tones of various frequencies has different reflective properties at each frequency against different surfaces of differing materials, densities, distances, and shapes, is employed to test the various features of the environment across the frequency range, giving the bird a real sense of the nature of the things it is encountering, their positions... and, most importantly, what may lie beyond them, as sound may bounce off the objects at angles, and travel behind them, before returning.
The continuation of song allows the bird to test the environment repeatedly, so that it can build a picture of those things that are static, and which are moving, and likely to pose an unpredictable problem (cars, other animals etc.).


The Magnificent Bird Brain

All of this builds to a complete language and understanding of sound, through an innate knowledge of the Doppler effect, acoustics, reflectivity and sonic absorbency of materials, and other properties of sound beyond anything humans could conceive of.
The bird being entirely aware of practically everything around it in such a deeply connected way as to almost amount to what we would consider one step short of psychic ability.
Making the much laboured use of the term 'bird brained' entirely redundant, as this level of subtle complexity would amount to one of the wonders of the world.

Returning to the Blackbird, it becomes apparent in light of this theory that by singing at the start of the day, and at the end would effectively be the act of creating a memory of the world around it. It sings at the end of the day to take a sonar snapshot of environment, and again in the morning in order to determine what has changed in the intervening period.


The information super sky-way

Furthermore... each bird would be intimately acquainted with these methods used by other species of bird, as they are founded on the same principles, and employ similar techniques, albeit in different 'dialects' and 'languages'- the pigeon will use it's familiar warbling coo, some birds will click, or trill a song, others offer low frequency hums etc.
This means that each bird not only has it's own ability to test and map the environment in this way to rely on, but use the songs and sounds of all other surrounding birds to assist this mental 'imaging' process, and by listening to their ambient chatter, can acknowledge their positions, orientations and 'see' what they see by recognising the tones they are employing which are suggestive of the materials they are testing. Just what they range of environmental appreciation would therefore be is potentially vast, and as long as they can hear a bird in ear shot they can 'know' what they know about their immediate surroundings.
A very real 'internet' of information conveyed through the air, between an intimately and profoundly interconnected series of life forms more ancient, and effective than our internet could ever hope to achieve!

To test this theory, and investigate it's potential validity, it would be necessary to track birds, and compare their songs in different locations and situations not simply regarding their calls concerning those most basic communicative sounds mentioned earlier (food, mating, territorial concerns etc.) but, as I don't believe anyone has as yet done to my knowledge, in comparison to the shapes, materials, and objects found in one location to another. Where a regular and common object would be found in many separate locations for example, the series of tones used would be similar accounting for proximity to the bird etc.

And finally, if this were the case, the wings of the bird themselves could also serve as an integral part of this function, as well as enabling flight, by acting as 'satellite dishes' which receive and amplify the sound as it flies (look at the Kestrel as it hovers over a field looking for prey... although it can see a tiny movement in the grass, it may be that it uses it's eyes only to zero in on the prey, having first located it by 'hearing it through it's wings'.

So next time you are outside, and hear the songs of birds, have a listen, and wonder... is there more to it than we have hitherto previously thought?

Are these creatures still more incredible than we already thought they were?

...or is it just my imagination?

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(addition- The Acoustic Properties of Animal Fur)

Having previously proposed a theory regarding the nature and possible meanings of bird song (Idea: Bird Song Theory), it occurred to me that if nature had over the course of the ages bestowed such an ability to sonically map an environment in this way upon birds, then nature would also through the process of natural selection according to the evolutionary theory have also engendered a corresponding adaptation through physical changes in the animal world too in response.

If you would for the sake of this argument accept that my proposed theory was correct, and also that the processes of evolution as we are given to understand them were also indeed true, then the ability of some class of animals, in this case birds, to employ echo-location and possible evaluation of it's surroundings would have significant repercussions both for the predators which stalk them and include some such birds in their diet, and for the prey themselves of larger birds who do themselves prey on smaller animals and often other birds too.
Such an advantage as this would render potential predators entirely unable to successfully catch and kill the birds, as the birds would have the most effective method of avoiding being caught... the awareness of the presence of a threat before it is in range to strike.
This in turn would mean that such predators would long ago have died out through starvation, and others of the species would have evolved along an alternate evolutionary path which provides for their dietary needs, such as vegetarianism, or a different choice of prey, the greater success of this branch of that species becoming the most successful or 'fittest', and entirely replacing the former's predatory habits as to entirely change the prevailing characteristics of that species in it's entirety.

And conversely, those birds who would employ such means for predation themselves would have been so successful in their ability to catch and kill it's prey that it would have annihilated the prey and rendered it extinct, in which case the predatory bird itself would again have starved to extinction in that form through being over-successful, and adapted along a different evolutionary path once again.

But clearly this has not, and is not the case, as we may still observe the Kestrel, the Eagles and Sparrow Hawks continuing to hunt for their particular prey, and the birds which are most commonly prey themselves, along with the small animals who may be included in a predator's diet continuing to thrive, or at the very least exist.

In this case, I must at first glance simply admit my theory is completely wrong, and abandon it absolutely now, or propose a 'counterbalance' to the advantage that such sonic ability would engender.

...And I believe I can.

Indeed, in doing so, I not only believe that this counterbalance theory would go a long way to addressing this vulnerability to criticism and disproving of the theory, but in fact offer a line of inquiry and a means itself by which my original Bird Song Theory could be proved... through providing an empirical means of evidence in it's support.

And that counterbalance is as follows:

Just as the ability to sonically map and evaluate an environment as I have proposed would have been brought about by the process of natural selection, with those birds in who this burgeoning ability, or nascent set of spontaneous mutations had offered significant defence against attack, and making them more likely to survive and pass on that mutation to the next generations who then in turn develop it through the ages, and those birds who don't have it being more and more likely to be hunted to extinction, until they are entirely replaced by birds with this new ability... so the predators (and in the case of the birds of prey... the prey themselves) would also in like manner have to respond through the same process, with those predators who's individual physical characteristics most allow them to avoid detection, and therefore be more successful in the hunt continuing to survive, and procreate, and continue this ability, while those least suited to avoiding such detection will inevitably die out through lack of success... until they are entirely replaced by the more successful variant of the species.

This applies to the prey animals also.

And that both prey and predators continue to exist, and that neither has obliterated the other either through over success in hunting the other to extinction, or being hunted to extinction can be evidence in itself that a balance exists of the successful and unsuccessful of both ends of the equation, and further more, that this must be an ongoing process of mutation and response.

So where should we look for this balancing mutation, or evolutionary response to my theory?

Well, as I have proposed a theory concerning the acoustic abilities of birds, it should stand to reason that any response to such a massive advantage in the predators of birds which could equal it, and restore the balance must also be an acoustic characteristic in the predator. Again, the prey of birds of prey also (small animals), must have this response through an acoustic characteristic.

And I have already suggested the possible answer earlier, when I suggested that the avoidance of detection would be the determining factor in the success of a species to predate.
That they could do so would mean that they themselves are undetectable to some, if not most sonic means of evaluation with regards to the information the bird may discern from the sound of it's song bouncing back to them and revealing the properties of the object resounded against.

And as practically every animal is covered with fur or feathers of some description for thermal, and visual camouflage reasons, it must be here that we could possibly detect the reason why they are not detectable... through the acoustic properties of fur and feathers, in how they return, deflect , and even absorb sound.

The successful predator or potential prey is the one who's fur in this case would reveal least about it to a sonic observer like a bird.

So by studying the Acoustic Properties of Fur, Feathers, and other such animal skins and outer surfaces in general, it would be possible to establish that such properties not only support my theory, and stand as evidence in this way, but also allow us to gain a picture of which methods are most successful in this regard, and what those properties are that that make them so.


It is a similar method to this remember, that first gave us Radar to detect air craft, then the stealth bomber in response to this innovation in order to avoid it's detection by this means.

( we gasp in awe at these technological wonders of ours, and congratulate ourselves at how clever we have been in 'inventing' them... when, as I propose in my original theory of bird song, and now this counter-part theory, nature got there first, millions of years ago, and continues to refine these methods. And our technology in light of this looks crude and clunky by comparison)