quote:
Today, some scientists estimate about 14 million species in existence (other estimates range from 1.6 to 80 million). Some also estimate 40,000 species become extinct every year (granted, no scientist knows exactly how many species become extinct each year, so feel free to fill in the estimate you feel is appropriate). Assuming the amount of species that existed when God created us (I know many will object to my plug for the Big Guy, but so what!), why is it hard to believe there would be similarities among species. I can’t explain the similarities, but I also know there are far more differences. The distance between an ape who can not read or write and a descendant of Adam who can compose a musical masterpiece or send someone to the moon is the distance of infinity (H. Hanegraaff). I don’t believe just because we have anatomical, genetic, and behavioral resemblances I should automatically assume a chimpanzee is my cousin. Email me 50 of your best drawn original designs and I guarantee I will be able to classify them into different categories based on similarities. Then try 14 million.
We can do a quick back of the envelope calculation to test this - the assertion here is, that with 14 million species (lets call it 80 million) then of course you would expect to see similarities. The question between chimps and humans is whether you would expect to see 95% of the dna base pairs in the same order, by chance alone, given a population of 8 *10^7.
Probability of selecting n pairs from N possible = (N-n)!/N!
N = no of base pairs = 3*10^9
n = base pair matches between human and chimps = 95%*3*10^9 = 2.85*10^9
So, approximating conservatively at every turn:
(N-n)!/N! = 1/(3,000,000,000*2,999,999,999*......*2,850,000,000)
Note that very conservatively , we can call this 2.85^(-150*10^6)
Note also that 2.85^(-150*10^6) = 10^(-68*10^6) (rounding conservatively)
We have a population of 8*10^7. So chance of this occuring by random is:
8*10^7*10(-68*10^6) = approx 10^(-68*10^6-
8) being conservative!
i.e chances are 1 in 10^(68 million) -
1 with 68 million zeroes after it, if we bend over backwards to make conservative approximations.
I may be a little rusty, so grateful if someone could check the maths.
PE
edited to add: I'm glad nobody's responded to this as I'm now of the opinion that its bollox.
It doesn't take into account the fact that there are only 4 possible base pairs. The calculation is a lot simpler done this way - all we are saying is that 95% of 3bn base pairs are identical, so the chances of this are:
(1/4)^(95%*3bn) {ignoring the 3/4* 10^(150,000,000) term} = 1/4^(2.85bn) = 10^(-1.7*10^9).
My apologies Blanko, the chances should only be
1 in 1 with 1.7 billion zeroes after it.
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Reading computer manuals without the hardware is as frustrating as reading sex manuals without the software - Clarke's 69th Law
[This message has been edited by Primordial Egg, 02-11-2003]
[This message has been edited by Primordial Egg, 02-11-2003]