Jerry Johnson writes:
Hi all,
I read that phylogenetic trees are one of the strongest evidence of evolution, because we get a very similar trees for different genes and proteins. But I can't find anywhere ANY concrete/specific numbers. How many phylogenetic trees where constructed so far? 1000? 50,000? a million? How similar are they to one another? 99%? 95%? 80%?
I would really like to see some numbers, where can I find them?
I'm asking this because I came across a video claiming that phylogenetic trees do NOT support evolution:
Is Homology Evidence for Evolution? | Long Story Short
So, if you have some numbers it will really help.
Thanks.
(I wanted to ask this in the "Biological Evolution" forum but I got a message telling me that I can post only here)
There are a couple problems with using homology to determine relatedness. The first is if you only use the coding portion of the genome and ignore the non-coding portions (which control the coding portions), you can come to very incorrect conclusions. For example, crocodiles have a beta-keratin gene so some may jump to the conclusion that that crocodiles are somehow related to birds. The problem is that the non-coding regions determine the structure of the beta-keratin. Therefore the non-coding portion has to evolve as well to change the scale formation into feathers and they have to be the correct kind of feathers. The second problem is that the mathematics which is used to determine relatedness based on homologous portions of genomes in different species is incorrect. If you want to see how they do that calculation, you can read about it here. If you don't understand the mathematic of Markov chains, this link will not make sense but I assure, their math is incorrect.
Models of DNA evolution - Wikipedia
Don't expect any of the posters on this forum to correctly explain this math.