Creationism in Crisis - How A 700-Million-Year-Old Chance Mutation Could Explain Why We Have Limbs

New research suggests a mistake in DNA millions of years ago could explain why the human body is so complex today.

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A graphic representation of the DNA sequence

How a 700-million-year-old DNA glitch could explain why humans have limbs | National Post

700 million years ago in a remote ancestor of all terrestrial tetrapods - which includes all amphibians, reptiles, birds and mammals, a mutation in a gene happened. To begin with this made no difference because the mutation was neutral - neither deleterious nor advantageous.

But later on, it became the mutation that made the evolution of limbs possible, in an illustration of how redundant or neutral DNA can later be exapted for new functions and structures.

This may seem highly improbable to anyone who doesn't understand how natural selection ensure that beneficial traits accumulate and increase in the species gene pool but in fact, there have been several such chance mutations that opened up the possibility of a new direction in evolution in human genetic history.

Creationism in Crisis - How De Novo Genes Arise (And Another Creationist Dogma Bites The Dust)

The whole genome of several tens of primates and mammals is known. Comparison of genomes allows for studying the evolution of individual genes.

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New genes can arise from nothing | HiLIFE – Helsinki Institute of Life Science | University of Helsinki

Present a creationist with a puzzle like, where does new genetic information in the form of new functional genes come from and a typical response will be, "Er... I can't imagine how that's possible... so God did it!". This of course is based on the foundational fallacies of creationism, and most religious apologetics - the argument from ignorant incredulity, and the false dichotomy fallacy.

This intellectual dishonesty appeals to people who are satisfied with not knowing and aren't bothered about the truth, so long as they have an excuse for pretending they know the answer

By contrast, present a scientist with the same question, and the response will probably be, "I don't know, so how can we find out?", because admitting ignorance is the foundation of good science. This approach appeals to people who have the humility to admit they don't know and who are interested enough in truth to want to find out.

An example of this was published recently by three researchers from the Institute of Biotechnology, Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland, who decided to address the question of where de novo genes arise in the genome, seemingly from nowhere.

This question arose from the observation that a comparison between human and other primate genomes shows that a number of microRNA (miRNA) sequences arose within the human genome, and the genome of other apes apparently as single mutation events.

In addition to the 20,000 genes in the human genome, there are thousands of miRNA sequences of about 22 base-pairs which have a regulatory function. Their role is to stop messenger RNA (mRNA) from continuing to make proteins when enough have been made. They do this by blocking the mRNA molecules and to do this they need to be folded in half like a hairpin. This folding means that they need to be 'palindromes', i.e., reading the same forward as backward, so, when folded in half, each base lines up with a copy of itself.

So, the question was, how do these palindrome miRNAs arise?

Creating Life By Chance Alone

Darwin's "warm little pond"

Chances of first life improved by weighted dice - life - 18 September 2014 - New Scientist

"How did life first arise on Earth?" is one of those questions like "What caused the Big Bang?" that creationists and religious apologists love because science either doesn't yet have an answer, or the real answer seems counter-intuitive and thus can be dismissed in front of an audience conditioned to assume that the Universe and everything in it - apart from their assumed god - should be easy to understand and makes intuitive sense even with little or no knowledge of the subject. The answer that the BB was a quantum event and so did not necessarily

Why You?

Orange and Yellow, Mark Rothko
Like the Anthropic Principle, the deeper you look into it the more you understand.

You are one of the lucky ones because you are alive. You are special. You are unique in the history of the cosmos; so is everyone else, and every other living thing. None of us has existed before and we never will again. Of all the possible humans and all the possible forms of life, only a very tiny fraction will actually exist.

Why can we say this?

Because the process of producing a new individual ensures that the genes get shuffled and there are far more possible combinations of genes than there are humans alive now or have ever been alive, so the chances of producing exactly you, of all the trillions of possible humans, is almost vanishingly small.

And yet, given the nature of human reproduction, once the conditions for one of several million sperm finding and fertilizing an ovum had been created, the likelihood of producing a human being was highly likely. The only thing that was unpredictable was exactly what hand of genes that individual would be dealt by the process.