- The genome of the sea anemone, one of the oldest living animal species on Earth, shares a surprising degree of similarity with the genome of vertebrates, researchers report in this week's Science. The study also found that these similarities were absent from fruit fly and nematode genomes, contradicting the widely held belief that organisms become more complex through evolution. The findings suggest that the ancestral animal genome was quite complex, and fly and worm genomes lost some of that intricacy as they evolved.
- The authors found that the sea anemone genome contains about 450 million base pairs and 18,000 protein-coding genes. They identified many gene families common to all sequenced animals. "We have this basic toolkit now for the whole animal kingdom," senior author Daniel S. Rokhsar of JGI and the University of California, Berkeley, told The Scientist. "It gives a kind of unity to all animals that I think is kind of surprising."
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Understand, Sea Anemone came onto the scene perhaps around 500 million years ago so far as we know. Anatomically modern humans much more recent, like it is said between 125 to 200k years ago. Here's another article in Nature, Evolutionary biology: Small regulatory RNAs pitch in (requires paid access), but is summarises:
- How did organismal complexity evolve at a cellular level, and how does a genome encode it? The answer might lie in differences, not in the number of genes an organism has, but rather in the regulation of gene expression.
It is commonly believed that complex organisms arose from simple ones. Yet analyses of genomes and of their transcribed genes in various organisms reveal1, 2 that, as far as protein-coding genes are concerned, the repertoire of a sea anemone — a rather simple, evolutionarily basal animal — is almost as complex as that of a human.
The more important question however, isn't how similar we are, but rather the differences. If we go by such studies above which support a "basic genetic toolkit" for the whole animal kingdom, then evidently the complexity of all species is much the same -- again, as far as protein-coding genes (the non-"junk" coding DNA), genomes in sea anemone are as complex as found in us humans.
Now I'm not saying evolution can't explain such, indeed, I think it can explain anything we come across. While it's a sword to Darwin's Evolution, the theory itself has evolved into something that seems able to cover scenarios we wouldn't predict. Yet, while explanations can exist, such does not mean they have the greatest explanatory power.
To provide an alternative explanation, it's articles like this that make me believe Progressive Creation makes greater sense -- God re-using and adapting genetic code across created species. Rather than a thorough-going evolution, wherein the idea is that things evolve, de-evolution I see is better explains by spontaneous creation (providing the "toolkit" and/or new genetic information) followed by a diminishing of what was created spawning new species through mutations, natural selection and the like.