Bats are a remarkable example of animals that people can learn from. In the case of bats, animals are teaching advanced engineering! We finally figured out in the 20th Century the highly technical principles behind the bat’s echolocation and copied them to create sonar and radar systems.
Echolocation is the use of sound waves and echoes to determine where objects are in space, and bats are experts at it. Not all bats use echolocation, but over half of the almost-thousand species of bats do. Bats use “both constant frequencies (CF calls) and varying frequencies that are frequently modulated (FM calls). Most bats produce a complicated sequence of calls, combining CF and FM components.”[1] In their calls, bats use two different types of frequency structures to acquire information. The FM is a broadband signal, sweeping through a range of frequencies. This signal is used to precisely locate an insect and it reduces background noise of large objects. On the other hand, a CF tone is a narrowband signal; the sound stays constant at one frequency. The CF tone gives feedback on the velocity of a target and the fluttering of its wings as Doppler shifted frequencies (alteration in sound wave frequency). * When bats emit sound waves as clicks or chirps from their mouth or, in rare cases, the nose, these sound waves hit an object. By the intensity of the returning echo, bats not only can ascertain where an object is, but its size and shape. Bats can pinpoint objects as thin as a thread![2] So the bat’s ears are acting as receivers, and its clicks are equivalent to the electromagnetic waves of radar systems such as those used to locate planes.
Echolocation requires flawless execution. For example, the bat has to decide at what rate to pulse its sounds. When a bat is searching for insects, it may pulse slower; that is, have a longer interval (100 milliseconds) between calls. However, as the bat gets closer to a flying insect, it has to increase the rate of call-repetition (an interval of only 5ms) so it can keep updating information on the location of the target. Bats can pulse their sounds with incredible speeds, up to 200 clicks a second, after they detect potential prey. Understandably, these clicks are referred to as a terminal buzz! Since bats use echolocation to orient themselves as well as to locate dinner, their auditory systems would have to be created for this purpose and fully functioning from the beginning. The oldest bat fossils ever found support this fact; they look like the bat skeletons of today.
Bat sounds are extremely loud, equal to a smoke alarm going off four inches from your ear![3] Fortunately, they are ultrasonic, too high for the human ear to hear. However, this brings up an engineering-design problem. How can the bat’s sensitive ears not be damaged when it blasts out sounds at 60-140 decibels? Outspoken atheist Richard Dawkins succinctly explains: “Now here is the problem that would strike the engineer trying to design a bat-like machine. When an analogous problem struck the designers of radar in the Second World War, they hit upon a solution which they called ‘send/receive’ radar. The radar signals were sent out in necessarily very powerful pulses, which might have damaged the highly sensitive antennas waiting for the faint returning echoes. Engineers came up with the idea to turn off the sending.” To clarify: “The ‘send/receive’ circuit temporarily disconnected the receiving antenna just before the outgoing pulse was about to be emitted, then switched [it] on again in time to receive the echo. The bats developed send/receive switching technology long long ago...” [4]
Dawkins uses anthropomorphic language, claiming bats did the developmental engineering. People are forced to ludicrously assign creative abilities to the animal, itself, when they deny there’s a Creator. Engineers in WWII copied the engineering of the bat, but not the engineering by the bat. As Dawkins illustrates, echolocation entails solving complex problems that require innovative designing.
The “send/receive technology” of a bat refers to the working of the bat’s ear. Analogous to man-made radar, the bat shuts off his ear by contracting muscles to prevent three bones in the ear from transmitting sound. Dawkins elaborates: “The mounting and hinging of these three bones, by the way, is exactly as a hi-fi engineer might have designed it to serve a necessary ‘impedance-matching’ function.” The ear closes off sound before each loud pulse to avoid damage. Then…“the ear returns to maximal sensitivity just in time for the returning echo. This send/receive switching system works only if split-second accuracy in timing is maintained.”[5] [Emphasis is mine to call attention to the wording Dawkins uses to describe the technical aspects of a bat.] If reality is accurately described, words like “engineered” and “designed” can hardly be avoided.
Though Dawkins does not want to credit a Creator, his language points to design in describing how bats function. [Again, emphasis is mine.] A “clever idea that might occur to the engineer, especially one interested in measuring the speed of a moving target, is to exploit what physicists call the Doppler Shift.”[6] Bats do exactly this; by the echo, the bat determines if an insect is moving closer or further away from it. “Echo-sounding by bats is just one of the thousands of examples that I could have chosen to make the point about good design. Animals give the appearance of having been designed by a theoretically sophisticated and practically ingenious physicist or engineer, but…”[7] Sometimes things really are what they seem, Mr. Dawkins. Animals have the appearance of being designed because—wait for it—they are designed.
*To better understand the Doppler shift, think of the sound of an ambulance speeding by you. You will hear a sudden drop in pitch as it races by.
[1] http://www.scientificamerican.com/article/how-do-bats-echolocate-an/
[2] http://en.wikipedia.org/wiki/Animal_echolocation
[3] http://www.scientificamerican.com/article/how-do-bats-echolocate-an/
[4] Dawkins, Richard. The Blind Watchmaker. (27).
[5] Dawkins (27).
[6] Dawkins (29).
[7] Dawkins (36).
Echolocation is the use of sound waves and echoes to determine where objects are in space, and bats are experts at it. Not all bats use echolocation, but over half of the almost-thousand species of bats do. Bats use “both constant frequencies (CF calls) and varying frequencies that are frequently modulated (FM calls). Most bats produce a complicated sequence of calls, combining CF and FM components.”[1] In their calls, bats use two different types of frequency structures to acquire information. The FM is a broadband signal, sweeping through a range of frequencies. This signal is used to precisely locate an insect and it reduces background noise of large objects. On the other hand, a CF tone is a narrowband signal; the sound stays constant at one frequency. The CF tone gives feedback on the velocity of a target and the fluttering of its wings as Doppler shifted frequencies (alteration in sound wave frequency). * When bats emit sound waves as clicks or chirps from their mouth or, in rare cases, the nose, these sound waves hit an object. By the intensity of the returning echo, bats not only can ascertain where an object is, but its size and shape. Bats can pinpoint objects as thin as a thread![2] So the bat’s ears are acting as receivers, and its clicks are equivalent to the electromagnetic waves of radar systems such as those used to locate planes.
Echolocation requires flawless execution. For example, the bat has to decide at what rate to pulse its sounds. When a bat is searching for insects, it may pulse slower; that is, have a longer interval (100 milliseconds) between calls. However, as the bat gets closer to a flying insect, it has to increase the rate of call-repetition (an interval of only 5ms) so it can keep updating information on the location of the target. Bats can pulse their sounds with incredible speeds, up to 200 clicks a second, after they detect potential prey. Understandably, these clicks are referred to as a terminal buzz! Since bats use echolocation to orient themselves as well as to locate dinner, their auditory systems would have to be created for this purpose and fully functioning from the beginning. The oldest bat fossils ever found support this fact; they look like the bat skeletons of today.
Bat sounds are extremely loud, equal to a smoke alarm going off four inches from your ear![3] Fortunately, they are ultrasonic, too high for the human ear to hear. However, this brings up an engineering-design problem. How can the bat’s sensitive ears not be damaged when it blasts out sounds at 60-140 decibels? Outspoken atheist Richard Dawkins succinctly explains: “Now here is the problem that would strike the engineer trying to design a bat-like machine. When an analogous problem struck the designers of radar in the Second World War, they hit upon a solution which they called ‘send/receive’ radar. The radar signals were sent out in necessarily very powerful pulses, which might have damaged the highly sensitive antennas waiting for the faint returning echoes. Engineers came up with the idea to turn off the sending.” To clarify: “The ‘send/receive’ circuit temporarily disconnected the receiving antenna just before the outgoing pulse was about to be emitted, then switched [it] on again in time to receive the echo. The bats developed send/receive switching technology long long ago...” [4]
Dawkins uses anthropomorphic language, claiming bats did the developmental engineering. People are forced to ludicrously assign creative abilities to the animal, itself, when they deny there’s a Creator. Engineers in WWII copied the engineering of the bat, but not the engineering by the bat. As Dawkins illustrates, echolocation entails solving complex problems that require innovative designing.
The “send/receive technology” of a bat refers to the working of the bat’s ear. Analogous to man-made radar, the bat shuts off his ear by contracting muscles to prevent three bones in the ear from transmitting sound. Dawkins elaborates: “The mounting and hinging of these three bones, by the way, is exactly as a hi-fi engineer might have designed it to serve a necessary ‘impedance-matching’ function.” The ear closes off sound before each loud pulse to avoid damage. Then…“the ear returns to maximal sensitivity just in time for the returning echo. This send/receive switching system works only if split-second accuracy in timing is maintained.”[5] [Emphasis is mine to call attention to the wording Dawkins uses to describe the technical aspects of a bat.] If reality is accurately described, words like “engineered” and “designed” can hardly be avoided.
Though Dawkins does not want to credit a Creator, his language points to design in describing how bats function. [Again, emphasis is mine.] A “clever idea that might occur to the engineer, especially one interested in measuring the speed of a moving target, is to exploit what physicists call the Doppler Shift.”[6] Bats do exactly this; by the echo, the bat determines if an insect is moving closer or further away from it. “Echo-sounding by bats is just one of the thousands of examples that I could have chosen to make the point about good design. Animals give the appearance of having been designed by a theoretically sophisticated and practically ingenious physicist or engineer, but…”[7] Sometimes things really are what they seem, Mr. Dawkins. Animals have the appearance of being designed because—wait for it—they are designed.
*To better understand the Doppler shift, think of the sound of an ambulance speeding by you. You will hear a sudden drop in pitch as it races by.
[1] http://www.scientificamerican.com/article/how-do-bats-echolocate-an/
[2] http://en.wikipedia.org/wiki/Animal_echolocation
[3] http://www.scientificamerican.com/article/how-do-bats-echolocate-an/
[4] Dawkins, Richard. The Blind Watchmaker. (27).
[5] Dawkins (27).
[6] Dawkins (29).
[7] Dawkins (36).
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