UltraSound and Evolution

Barely mentioned in the scientific media, heating from sonic waves can activate genes:

Using mice engineered with a bioluminescent gene containing a heat-sensitive stretch of DNA, they focused high-intensity ultrasound pulses on a 0.5-millimeter-wide patch of the mice's legs, heating up that area just below the skin's surface to about 43 degrees Celsius (109 degrees Fahrenheit). Light given off revealed that the gene became active.

Call me stupid, but could there be a link between why dogs have evolved to hear ultrasounds (for no purpose that I could find), and the ability of these waves to activate genes, and evolution?

Rapid Darwinian Evolution

Simply stated, Darwin told us that evolution revolves around the survival of the fittest - those least fit don't make it, and therefore they don't leave offspring. Those most fit will prosper, and their offspring will inherit the genes that gave them that advantage.

Most experts would say that evolution is a slow process. Some say it can happen rapidly (see "punctuated equilibrium"). I figure both are correct - it can happen fast, medium or slow. The more extreme the circumstances, the more rapid the evolution.

In late 2007 SciAm published an opinion piece that highlights just how rapidly evolution can occur:

Brought to Queensland in 1935 to combat beetles infesting sugarcane fields, the [Cane]toads have spread out from their point of entry like the shock waves of a bomb, warty legs and oversize tongues jettisoned into every conceivable ecological crack.

...Recent research... has shown that the toads are evolving as they spread, perfecting their ability to adapt to the Australian landscape. The toads at the front edge of the invasion now have smaller bodies, reduced toxicity and relatively longer legs, apparently because individuals with those traits were having greater success. The native fauna has evolved in response: the mouths of some snake species are getting smaller, for instance, because so many of the snakes with big mouths were eating the poisonous cane toads and dying off.

In a global cataclysm scenario, evolutionary pressures can become extreme. Larger, less-populous species are more likely to become extinct (less places to hide, less numbers). The butterfly effect of this can wreak havoc on the what was previously a well-balanced scenario. Changed landscapes and climates can suddenly create challenges, giving advantage to those best suited to the changed situation.

Unless we have scientists observing the the most extreme circumstances nature can toss our way, we will be unable to realise how rapid evolution can be - we will be unable to realise that gaps in the evolutionary tree come down to the sheer speed of the evolution itself.

Where did we come from, originally?

Regarding the very beginning, ie DNA, the recent analysis of an Australian meteorite provides evidence for Carl Sagan's idea that we are of extra-terrestial origins:

Researchers discovered the organic molecules uracil and xanthine in the meteorite and confirmed they could not have formed on Earth. These molecules, called nucleobases, are precursors to DNA...

"Emergent life systems may have adopted nucleobases from meteoritic fragments for use in an early and primitive genetic material, enabling them to pass on their successful features to the next generations," said study leader Zita Martins of Imperial College London.

Regarding our evolution from apes to humans, I came across an article at Nature.com that proposes a nuclear reactor could occur at the base of Earth’s mantle - providing heat and also radiation. The key factor for me is this:

Yet it is clear that natural nuclear reactors can occur. Crustal rocks at Oklo in Gabon, Africa, bear unambiguous evidence of spontaneous ignition of uranium fission in mineral deposits 1.7 billion years ago.

As humans, we originated in Africa. Radiation made it to the surface in Africa. Radiation causes mutations. Mutations can lead to evolution.

Supporting Evolution Snippets from New Scientist

Can mutation really lead to the evolution of new species?

Yes. Several species of abalone shellfish have evolved due to mutations in the protein "key" on the surface of sperm that binds to a "lock" on the surface of eggs. This might appear impossible, but it turns out that some eggs are prepared to be penetrated by deviant sperm. The same thing can happen in fruit flies, and likely in many other groups too. In yeasts, the mutations that led to some new species forming have not only been identified, they have even been reversed.

http://www.newscientist.com/channel/life/dn13673-evolution-myths-mutations-can-only-destroy-information.html

Organisms do not always hang about waiting for a helpful mutation to occur. For instance, the parasite that causes sleeping sickness has thousands of spare genes for its coat proteins, which it mixes and matches to generate new coats faster than its host's immune system can keep up.

More controversially, a few biologists think some microbes may have evolved mechanisms for boosting the mutation rate in specific genes when they are struggling to cope with a changing environment, or for "storing up" variation for when it is needed

http://www.newscientist.com/channel/life/dn13698-evolution-myths-evolution-is-random.html

It won't be long (hopefully pre-2012) before a prominent scientist dares to suggest that we evolve the the way our DNA chooses, into new species.

Thanks Cataclysm, for Blue Eyes

Further (minor) evidence for my evolution circa 10,000 BC theories:

A team of scientists has tracked down a genetic mutation that leads to blue eyes. The mutation occurred between 6,000 and 10,000 years ago. Before then, there were no blue eyes.

..."From this we can conclude that all blue-eyed individuals are linked to the same ancestor," Eiberg said. "They have all inherited the same switch at exactly the same spot in their DNA." Eiberg and his colleagues detailed their study in the Jan. 3 online edition of the journal Human Genetics.

That genetic switch somehow spread throughout Europe and now other parts of the world.

"The question really is, 'Why did we go from having nobody on Earth with blue eyes 10,000 years ago to having 20 or 40 percent of Europeans having blue eyes now?" Hawks said. "This gene does something good for people. It makes them have more kids."

http://www.livescience.com/health/080131-blue-eyes.html

Unless of course multiple people had the same mutation during the last cataclysm. My theory postulates that during a massive influx of cosmic rays, human DNA chose which mutations to repair, and which to leave be. I suggest that our DNA is happy to experiment with such things as size and colour - things that should not affect our function much, if at all.

Human evolution speeding up?

The pace of change accelerated about 40,000 years ago and then picked up even more with the advent of agriculture about 10,000 years ago, the study says.

...The biggest changes have come since the end of the last ice age, about 10,000 years ago, which opened up new environments for the quickly expanding human population to grow from millions to billions.

More people mean more mutations, Harpending noted.

"You are also giving them the potential to be adaptive mutations," said Brian Verrelli, who studies population genetics and evolution at Arizona State University in Tempe and was not involved in the research.

Hmmm...

Evolution has speed up since 10,00 years ago - for me this means since the last global cataclysm.

"More people means more mutations". How about, more cosmic rays meant more mutations!

Risk Distribution Law For Evolution

I've been saying for a long time that a bombardment of cosmic rays would cause high rates of mutations in humans, but our bodies are capable of repairing DNA damage, and can choose which damage to leave unfixed. That's correct - choose.

Now supporting evidence has arrived:

Barkai and her team discovered a sort of "risk distribution law" for evolution. They found that a genetic "phrase" that regularly shows up in the promoter region of genes (the bit of genetic code responsible for activating the gene) contains a key to gene conservation: The expression of a gene that contains the sequence TATA in its promoter is more likely to have evolved than that of a gene that does not have TATA in its promoter.

In other words, the level of risk appears to written in the gene code, in a way that's similar to financial risk analysis: When the cost of error is high, an investor's willingness to chance the risk is low, but if the cost of a mistake is negligible, even if the chance of making one is high, the possibility of gain may make the risk worthwhile. Evolution, it seems, discovered this principle millions of years before Wall Street. (more here)

Example:

Perhaps we could afford to mess with the size of our ears, but we would rather not take any risks with our eyes.

A gene associated with the size of ears might have the sequence TATA, so when mutated, the DNA is not repaired, and new sizes of ears develop. But a gene associated with the eye might not have the sequence TATA, so our body repairs any damage to it.

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This means that many humans can mutate in similar ways - and this gives us the potential to mutate into a new human species, via cosmic ray bombardment