You do not need a book, but just one word, to show that
species did not “form” or “evolve” through random mutations: “impossible”.
The probability that
a monkey pounding on a keyboard with 100 keys will come up with the word
“impossible”, without
counting the quotes and without uppercase characters requiring key
combinations, can be calculated as follows:
The probability for the monkey (or a random process) to
hit the first Character, an “i” on a keyboard is 1 out of 100 (101 key
keyboards are the most common – let’s imagine one key being disabled).
The probability for the first two characters (“im”)
to be hit, in the wanted position, is 1 out of 100 x 100, or 1 out of 1002 (or 104).
The probability for all the 10 characters in the word “impossible” to be
hit, in the proper sequence, is 1 out of 10010 (or 1020). This number is bigger
that the number of seconds since the beginning of the universe.
No random process pushing keyboard keys once every tenth
of a second, coming up with a 10-character long word once per second (we call
this an “occurrence”), is likely to have come up with the word “impossible”
since the beginning of time.
The number of seconds in an hour is 3600, in a day is
86,400, in a year is 31,536,000. This is (rounded up) 3.2 x 107 (seconds in a year).
The age of our solar system is estimated at about 5 Billion years, or 1.6 x 1017 seconds.
The age of the universe is estimated to be less than 25 Billion years, or .8 x 1018 seconds.
The age of our solar system is estimated at about 5 Billion years, or 1.6 x 1017 seconds.
The age of the universe is estimated to be less than 25 Billion years, or .8 x 1018 seconds.
Thus 100 Billion years (a mere 1011 years – four times what astronomers think the age
of the universe is) is less than 3.2 x 1018
seconds, a number two orders of magnitude smaller than the number of random
occurrences – one per second – which would be needed to possibly generate our
word by chance: 1020.
Our target word is a case of “irreduceable complexity”: We
want exactly the word “impossible” to be generated randomly as written. We do
not want to try until a half the word is generated, and then try many more
times to get the rest of the characters in sequence. We want the whole word to
be generated in one occurrence.
Another example of irreduceable complexity is a “jackpot”
combination of four specific symbols in a slot machine. We can use the same
formula to calculate the odds of winning when the machine has four wheels and
each wheel has a character set of ten unique symbols. In this case the number
of trials would be 104, and the probability of hitting the
jackpot would be of one in 10,000. This
is a relatively low probability, which would allow the owners to set a jackpot
prize of perhaps $1,000, when the cost of each “trial” is one quarter. In the
long run, the owners would make about $2,500 (ten thousand quarters) for each
jackpot they are likely to pay out (without considering other small prizes).
If the designers of the slot machines wanted to decrease the
probability of winning a jackpot, in order to possibly increase both the prizes
paid out and their earnings, they could either increase the number of unique
symbols on each wheel, or the number of wheels, or both. For example, in a slot
machine with 5 wheels and 16 unique symbols, the odds to win a jackpot would be
about one in a million (one in 106). The odds in our “impossible” example are
equivalent to hit a jackpot in a slot mahine with 10 wheels with 100 unique
symbols: 10010, or 1020:
A very skewed slot machine, where the odds of hitting the jack pot, even trying
one occurrence per second for 100 Billion years would be very close to zero.
The above calculations give us an idea of the numbers
involved in a random process of “generation”. We can
assume the number 1018
(the number of seconds in more than 31 billion years) as the maximum amount of
random occurrences possible, once per second, for a time approximately as long
as our universe has existed. This corresponds to the Maximum Complexity Limit
for a pattern or system that requires as many occurrences, once per second, to
be generated by a random physical process: The Maximum Complexity Limit for
Random Generation (MCLRG for short).
Some evolutionary biologists have suggested that random
mutations could explain how new species could be generated as the progenies of
existing species.
The idea of random mutations between one individual and its
progeny has an innate problem: By definition, a random mutation can apply to
some, or a large part, or most of the genetic information of the parent
individual. Assuming otherwise, would require some other intervening process.
For example, could an ape develop one more toe to be able to
grab things better? If we entertain other concepts, such as adaptation to the
environment, or some other theory, working in conjunction with random
mutations, then random mutations need to be severely limited, or any progeny
would have a very large probability of not being viable.
The more we limit the concept of random mutations, the more time is needed to produce their
intended effect (a genetically different viable individual). But we have seen
from our calculations that random variations (applied to non-trivial patterns)
do not have enough time to work their magic even if they happened once per
second for billions of years. Any severe restriction imposed on random
mutations by some other reasoning, for example by introducing a process of
adaptation involving several generations of individuals of that species, would
require more time and further invalidate the theory of random mutations.
Thus, considering
random mutations independently from other processes, the probability for a
particular random genetic mutation to generate a progeny able to survive or
thrive is equivalent to the probability of producing a viable individual
randomly from scratch.
As we read in the
“random mutation” literature, a mutation is “unrelated
to how useful that mutation would be”.
Mutations, in conformance with the theory, always include the possibility of
producing a different species altogether!
In today’s world of DNA and amino-acid sequences, we tend to
get distracted by the incredible details of microbiology. By using examples
taken from genetics in an argument, we can lose most of our listeners (and even
get ourselves lost) in the details of DNA sequencing.
For example, we could say that a DNA sequence of a sexually
reproducing mammal is millions of times more complicated that the word
“impossible” and it could not have been created randomly. We can say this
intuitively, but when we embark in a specific explanation we are bound to make
approximations and mistakes that a microbiologist will flag as errors in our
reasoning, invalidating our argument for the wrong reasons.
For this reason, we will follow a “low tech” approach that
most people can understand without knowledge of microbiology.
The main assumption, in order for the generation process to
work, is that an adult, sexually reproducing mammal must be generated in its
integrity, with all the elements necessary for it to survive, grow to adulthood
and reproduce itself. Our individual is irreduceably complex, as it needs
several organs to function and reproduce, such as:
- An endocrine system to regulate the body (including reproduction hormones);
- a respiratory system, to feed oxigen to its organs;
- a blood circulation system, to transport oxigen and nutrients to its organs;
- a stomach or some system to break down ingested food;
- a digestive system to absorb chemicals from food and feed the body;
- a filtering system to process and get rid of liquid waste;
- a skeleton, to support the individual;
- a brain, to search for food, escape attacks, defend itself, control its organs, etc.
- a vision system to identify food, enemies, etc.
- a muscular system to be able to grab, move, chew, etc.
- a lymphatic system to transport and methabolize the fluid in between cells;
- a nervous system to communicate commands to various muscles and organs;
- a skin system to enclose and protect its organs; and
- a reproductive system.
Our individual will need all of
the above systems (and probably more) to be fully functioning. If any of the
above systems failed, then the individual could not survive long enough to be
able to mate and reproduce.
Thus we can say that the above
fourteen systems represent a level of irreduceable complexity for a mammal to
become a candidate for the generation of a new species. All of the systems need
to be present, in a certain position with respect to, and connected to the
other systems. The relation among these systems is a much stronger and more
complex than just the positional order in our “impossible” word.
For example, each muscle in the
body needs to be attached in specific and multiple points to the skeleton, must
be connected in specific and multiple points to the nervous system, must be fed
in many points by the blood circulation system, etc. Thus the “positioning” of
the muscular system is not just a few bits of information describing its order
in a string of 14 characters, but requires perhaps thousands of pieces of
information specifying its relations with several other systems.
Thus by using with the analogy of
the word “impossible” and assuming that our new word (describing a mammal) is a
14-character word, we are making a great simplification.
To complete the analogy, we need
to think about what choices (or “character set”) are available for each system
(or “character”).
The simplest way is to think of
each system as using its own set of keys.
For example, in a working
endocrine system there are about 20 organs involved, each producing one or more
out of about 70 hormones, which need to be regulated using four signaling
systems through many feedback mechanisms, so that the production of these
hormones can start and stop as necessary. A simplified analogy could be having
a keyboard with 20 super-keys, which when pressed show a pull-down menu on a
screen with 4 selections, each invoking a pop-up window with 70 possible
choices. This analogy would give us 20 x 4 x 70 = 5,600 possible choices in our
endocrine system “character set”.
But this analogy is still very
simplified, because:
1.
In the above calculation we considered only the actual
hormones we know are essential, and the organs we know are involved, not all
the possible hormones that can be randomly created or all the possible organs
that can randomly be conceived.
2.
In the above description of the system we did not consider
many other choices which determine its functionality, such as the type of
organs or glands, their composition, size, structure, design, position in the
body, emittors and receptors of stimuli, design and functionality of the
feedback systems, and so on.
Even without knowing much about
biology we can guess that the number of choices required to generate a
functioning endocrine system are many thousands.
Thus our first “character” in our
“word” representing one mammal individual, would have to come from a choice set
of many thousands (certaily more than 5,600).
Without trying to recall basic
biology and describe each system in detail, we can simplify again and say that
each of our 14 systems will have a choice set of only 1,000. Even with this
generous simplification, a random process would still require 1,00014,
or 1042 number of “trials”, one occurrence per second, to
generate our individual mammal characteristics, which is still a number
incomparably bigger (22 orders of magnitude bigger) than the number of trials
required to generate the word “impossible” (1020).
We could forget about the real
complexity of these systems and assume that each of them could be described by
one character out of character set of 100, as if there were only 100 possible
choices to uniquely and completely define each system. Then our formula would
give us 10014 possible choices or a probability of one out of 1028
for our individual to be randomly defined. This is still eight orders of
magnitude bigger than our “impossible” example.
Thus, according to our calculations, not even one viable mammal animal species could have been “defined”
by random trials, once per second, during the time the universe has existed, rounded
up to 100 Billion years. We are very generous with the age of the universe as
well, even if the “Cambrian explosion” is estimated to have happened less than
1 Billion years ago.
Furthermore, how would the random
process know, without an “external intelligence” which combination is the right
one, once it is achieved? Through the process of elimination: Those individuals
that are not viable, or less able to cope, will be less likely to grow and
reproduce. The theory of random mutation implies a “meeting” between two
individuals of the same sexually reproducing species (Let’s forget about the
low probability of two individuals of the same species being randomly generated
in the same reproductive lifetime span – out of 100 Billion years. Let’s also
forget about the low probability of them meeting in the same spot). They need
time to growth to maturity, time for courting and reproduction, time for
testing their survival, dying, etc. These are all processes that require much
more time (several orders of magnitude bigger) than one second (which we
assumed in our calculation as the time between random occurrences).
Our explanations are hardly
necessary, since we intuitively know that the description of the
characteristics of an animal species must be more complex than the sequence of
ten characters, out of a regular keyboard, forming the word “impossible”.
Our simplifications were so great
and so many, that the same reasoning could be applied to any one system (or
sub-system, such as an eye, or even a single gene) and show that even this by
itself could not possibly be generated through random mutations.
In conclusion, a random mutation scenario for the generation
of animal species is so far from the realm of mathematical possibility to make
it ridiculous to entertain, even as
part of, or in combination to other possible processes or theories.
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