Now, it is true that mitochondrial organelles are quite unique and very interesting. Unlike any other organelle, except for chloroplasts, mitochondria appear to originate only from other mitochondria. They contain some of their own DNA, which is usually, but not always, circular – like circular bacterial DNA (there are also many organisms that have linear mitochondrial chromosomes with eukaryotic-style telomeres). Mitochondria also have their own transcriptional and translational machinery to decode DNA and messenger RNA and produce proteins. Also, mitochondrial ribosomes and transfer RNA molecules are similar to those found in bacteria, as are some of the components of their membranes. In 1970, these and other similar observations led Dr. Lynn Margulis to propose an extracellular origin for mitochondria in her book, Origin of Eukaryotic Cells (Margulis, 1970). However, despite having their own DNA, mitochondria do not contain anywhere near the amount of DNA needed to code for all mitochondria-specific proteins. Over 99% of the proteins needed for mitochondrial function are actually produced outside of the mitochondria themselves. The DNA needed to code for these proteins is located within the cell’s nucleus and the protein sequences are assembled in the cytoplasm of the cell before being imported into the mitochondria (Endo and Yamano, 2010). It is hypothesized that these necessary genes were once part of the mitochondrial genome, but were then transferred and incorporated into the eukaryotic nuclear DNA over time. Not surprisingly then, none of the initial mtDNAs investigated by detailed sequencing, including animal mtDNAs, look anything like a typical bacterial genome in the way in which genes are organized and expressed (Michael Gray, 2012).

It is interesting to note at this point that Margulis herself wasn’t really very Darwinian in her thinking. She opposed competition-oriented views of evolution and stressed the importance of symbiotic or cooperative relationships between species. She also argued that standard neo-Darwinism, which insists on the slow accrual of mutations by gene-level natural selection, “is in a complete funk” (Link).

But what about all of those similarities between mitochondria and bacteria? It would seem like these similarities should overwhelmingly support the theory of common ancestry between bacteria and mitochondria.

Well, the problem with Darwinian thinking in general is that too much emphasis is placed on the shared similarities between various creatures without sufficient consideration of the uniquely required functional differences. These required differences are what the Darwinian mechanism cannot reasonably explain beyond the lowest levels of functional complexity (or minimum structural threshold requirements). The fact of the matter is that no one has ever observed nor has anyone ever published a reasonable explanation for how random mutations combined with natural selection can produce any qualitatively novel protein-based biological system that requires more than a few hundred specifically arranged amino acid residues – this side of trillions upon trillions of years of time. Functionally complex systems that require a minimum of multiple proteins comprised of several thousand specifically-coded amino acid residue positions, like a rotary flagellar motility system or ATPsynthase (illustrated), simply don’t evolve. It just doesn’t happen nor is it remotely likely to happen in what anyone would call a reasonable amount of time (Link). And, when it comes to mitochondria, there are various uniquely functional features that are required for successful symbiosis – that bacteria simply do not have. In other words, getting a viable symbiotic relationship established to begin with isn’t so simple from a purely naturalistic perspective. More.

http://www.uncommondescent.com/origin-of-life/sean-pitman-on-evolution-of-mitochondria/

3
Virgil Cain March 4, 2016 at 11:44 am

Dawkins’ weasel is great support for What Dr Pittman wrote. The sentence “Methinks it is like a weasel” only works in one specific case, that is in the Shakespeare play that contains it. It is meaningless in every other piece of literature. It would only do any good if it arose and was properly integrated into that play.

And not surprisingly Dawkins and the evo-minions seem totally unaware of that fact.


4
seanpit March 4, 2016 at 3:58 pm

The problem with Zachriel’s evolution algorithms, as I’ve mentioned to him many times before, is the same problem Dawkins has with his evolution algorithm (“Methinks it is like a weasel”). Neither uses function-based selection where each mutation is functionally beneficial compared to what came before. All of these algorithms use “target sequences” that function as templates. Each additional match to this target sequence is defined as “selectable” in these evolution algorithms. That is why they work so well and so quickly.

The problem, of course, is that biological evolution does not and cannot work like this. Natural selection cannot preferentially select any novel mutation over any other until such a mutation comes along that actually produces some qualitatively novel functional change that also has a positive effect on reproductive fitness relative to all of the other individuals within that population. Using this Darwinian mechanism, finding novel functionality with greater and greater minimum size and/or specificity requirements becomes exponentially more and more difficult to achieve within a given span of time.

http://www.detectingdesign.com.....alculation

So, Dawkins and Zachriel need to go back to the drawing board and come up with a new evolutionary algorithm that actually reflects what we see in nature. If they do this, they will soon realize, if they are honest with themselves, that such algorithms stall out, in an exponential manner, with each step up the ladder of functional complexity