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Re: Reverse-engineering the T. rex genome
ered organism using a consensus sequence with
> strong statistical backing will not be the same as the
> ancestral organism, but I do wonder if it would be viable,
> and how close we could come to the ancestral animal.
Not very close. From what I've seen, any consensus remaining for example in
cytB is consensus across most amniotes (at least). Noise would be so strong
that it would even affect the nucear genome.
But you don't need to sequence all birds. Here's a shortcut:
take the chicken genome (complete) and the human genome (complete) and wait for
the first complete croc genome. Make consesnus between crock and chicken.
Compare to human. Take everything out that is consensus in all thre.. The
remainder - chicken-croc but not human consensus - is a rather good (thogh
somewhat overstimated) approximation of what you will at best be able to
achieve. If you want to get beyond that, you'd need for example a duck, ostrich
and passerine genome, to weed out any homoplasies between chicken and croc.
The point is that with increasing phylogenetic distinctness the consensus
becomes less and less until all that remains are the base positions absolutely
crucial for function. For much of the genome, the evolutionary time that has
passed between the "proto-avian" and "proto-tyrannosaurid" lineages' split is
sufficient to reach that point.
Now, what *could* perhaps be done is a Neoaves-wide comparison of genomic
structure, exon/intron distributions, karyotype etc. Especially when focusing
on paleognath and galloanserine *plesiomorph*ies (vs neoavian and crocodile
apomorphies), this could indeed yield some useful information regarding