Categories: "Science"

What makes us evolve, answering a creationist

I had a few comments from creationists left on my blog lately. One from somebody who identified themselves as '?':

i have a question...how did creatures change from generation to generation to be better suited for their environments? i mean, if i moved to (i don't know) africa, and i had kids with an another person with my skin color, the color wouldn't change in my great grand children to make them better suited for their environments. it's called mating with another type of your own species, not evolution right?

To start off I'll briefly talk about how variation comes about. If the first self-replicating molecule could create perfect copies of itself, there would be no evolution, the world would be full of clones of that original molecule. Evolution by natural selection requires variation for it to act upon. Originally all that variation came about by mutations, either errors copying the DNA (or RNA), or by damage from cosmic rays. If the changes were advantageous the mutation would spread throughout the population. Around 1-1.5 billion years ago another tool to increase the variation evolved sexual reproduction, no longer did life descended from those cells create clones of themselves, instead they would re-combine their DNA with that of another, ensuring that children are not clones of the parent. This variation also provided something else for natural selection to act upon.

Darker skin evolved in humans in Africa around 1.5 million years ago, back in the time of Homo ergaster, as we began to lose our hair. At some point mutations happened in a gene (or genes) which darkened our skin, this may of been gradual or happened in a single mutation. This mutation was beneficial because it better protected the body from ultra-violent radiation (previously our hair protected us against it), and alas it spread throughout the population.

Around 40000 years ago, Homo sapiens began to move north into Europe. At this point another mutation happened, we know it was a change in a single nucleotide, out of 3.1 billion which make up our DNA. This produced a pale skinned individual. Further north we required less protection from UV radiation so maintaining our dark skin became less important, but this also had a benefit, it increased the amount of vitamin D that Europeans who carried this mutation produced. Some lines of evidence such as cave paintings suggest some Europeans could of been dark skinned up until just 13000 years ago, today however 99% of Europeans carry the mutation.

The original question set up a premise that the skin of their descendants would not darken from living in Africa. Obviously it is impossible to predict random mutations in the future, and the selective value of dark or light skin is less than it used to be before we invented sun block and had better diets. But if the climate of Africa remained the same, and if you could stop your descendants from mating outside of your family (both of which aren't realistic in practice) the skin of your descendants would almost certainly darken. We've seen skin colour changes happen multiple times independently in human populations in the past, and they will undoubtedly happen in the future.

Given enough time if you could prevent your descendants from breeding with the rest of Homo sapiens they would eventually form a new species, enough mutations would of happened in each population, and as no changes would be passed back and forth between the two groups eventually they'd no longer be compatible, of course this could take anywhere from tens of thousands to hundreds of thousands of years for the differences to gradually build up.

Take our friend Su Kong, if the Earth went into a major ice age in the late 19th century and the rest of us were freezing to death around him (presumably we'd have to forget how to make hats too) his descendants could well make up Homo thefuture while Homo sapiens are strewn across a thin layer of dirt - so much for the species made in god's image!

Changes in our genes happen over time, and natural selection will act upon them.

it just doesn't make sense to me. i mean, all you have to do is think about evolution and it just doesnt make sense. u can't just scratch the surface. and also

Once you understand evolution it makes perfect sense, you develop an understanding, a real understanding of how life on Earth is so diverse, you see the interconnectedness of all life, how we are all descended from a four billion year old self-replicating molecule and you see that nothing is stationary and things are constantly changing.

how has evolution been scientifically proven? the only facts ive ever seen have DISPROVEN it.

I've never seen facts that disprove it, in fact everything has gone evolution's way, if genetics worked differently evolution could of been falsified etc. If anybody finds fossil rabbits in the pre-Cambrian that'll put a sizeable hole in the evolution by natural selection boat. If you're reading creationist sources, of which I am familiar, well let's just say somebody who spends their time studying the bible instead of the world probably isn't in a position to know a lot about the world.

Microsoft announce WorldWide Telescope

So today is the day I've been waiting for Microsoft officially announced WorldWide Telescope.

Sadly it isn't available yet for general download, but it will be sometime during the Spring.

WorldWide Telescope (WWT) is a rich visualization environment that functions as a virtual telescope, bringing together imagery from the best ground and space telescopes in the world for a seamless, guided exploration of the universe.

WorldWide Telescope, created with Microsoft's high-performance Visual Experience Engine™, enables seamless panning and zooming across the night sky blending terabytes of images, data, and stories from multiple sources over the Internet into a media-rich, immersive experience.

Microsoft WorldWide Telescope

This is what Dr. Roy Gould had to say about it:

The WorldWide Telescope takes the best images from the greatest telescopes on Earth ... and in space ... and assembles them into a seamless, holistic view of the universe. This new resource will change the way we do astronomy ... the way we teach astronomy ... and, most importantly, I think it's going to change the way we see ourselves in the universe.

Although obviously stunning are the pictures we can get nowadays, they lack context because there is no way to see what is outside the edges of the image. I still remember the first time I saw a really high resolution image of the Orion Molecular Cloud Complex, now we've all see images of the Horsehead Nebula and the Great Orion Nebula, but to see a huge portion of the sky in really high resolution and look at the structure to see that the bright nebulae we were used to seeing were simply areas of a much larger nebula condensing was incredible. This software does this for the whole sky, and not only in visible but other wavelengths too.

Space shuttle over the UK this evening

STS 122 launched yesterday on time (to my surprise after the weather forecast), and will, with the space station be visible over the UK.

This evening (8th) the ISS will pass overhead at about 17:55 (and later at 19:25), and the space shuttle will probably be between 10 and 20 minutes behind it.

Tomorrow (9th) the shuttle will be docking with the space station, I haven't been able to find out at what time, but if they haven't already docked by tomorrow evening they will be much closer in the sky, hopefully only a few seconds apart or less. It'll pass overhead at about 18:15.

To get exact times check Heavens Above. Be a tad sceptical with the times listed for the space shuttle as it is changing its orbit gradually which can often throw the numbers out.

Beatles crawling about NASA

Why the hell is NASA wasting public money on giving publicity to this group of attention seekers, yes I'm looking at you Paul McCartney.

In case you haven't heard NASA will be broadcasting the Beatles song Across the Universe towards Polaris on the 4th.

Amazing! Well done, NASA! Send my love to the aliens. All the best, Paul.

Yoko Ono of course had her bit to say as well.

I see that this is the beginning of the new age in which we will communicate with billions of planets across the universe.

As nutty as ever, has anybody told her that Polaris is 400 odd light years away? Wait, she probably doesn't even know what that means. Enjoy waiting 800 odd years for a response, if any, Yoko.

Why NASA are doing this is totally beyond me. There is zero scientific justification to this, all it seems to be doing is wasting US tax payers money on promoting the Beatles. NASA's budget is tight enough, with dozens of scientific programs being cut without wasting money on this nonsense.

If you want to send messages out into the cosmos (we've only done this once or twice before, it is expensive), at least do it properly. Use some mathematical sequence which can only be interpreted as artificial, and send it to high probability targets that are closer to the Earth - and then keep transmitting.

The private exploitation of space needs to stop, yes that means you too Richard Branson, Virgin Galactic - even the name is false advertising! I think its time for a campaign - Keep Space Public.

BBC Watchdog loses the plot over psychics

So I was half watching Watchdog yesterday, and a caught the presenter mention something about proving things about psychics, which sparked my interest.

Somebody sent them in some amulet to heal his aura, whatever that is. To which Nick Campbell said:

"If anyone tries to charge you for this sort of thing, psychic or not, they saw you coming"

That's a pretty crappy attitude to have. You could say the same thing about anything, if you gave a company money for a ticket you never got, they saw you coming. If you gave some company money for product X that doesn't work, they saw you coming. A significant part of the population are way too susceptible to this sort of woo woo, and it should not just be brushed aside.

You're supposed to be in favour of the consumer, no matter if they're handing their money over to so-called psychics with false claims or some greedy company or dodgy individuals.

So I did a bit of searching to see if there was any reason for this just popping up, and as it turns out on last week's episode they did a piece investigating some psychic whackjob who claims to do something or other and charges you thousands of pounds for the privilege.

After the piece was over it went back to the studio where Julia Bradbury said...

"Because of course there are genuine psychics out there"

*Bangs head on the desk*. WHAT?

"Because of course there are genuine psychics out there"

She was speaking to some bloke from the Office of Fair Trading, who strongly emphasised that every investigation they've done has revealed no genuine psychics.

Honestly what the hell.

So anyway, after watching yesterday's episode again to catch what Nick Campbell said, apparently they had a few letters from viewers stating that they think all psychics are "at it", he went on to say:

Proving the authenticity or otherwise of all psychics is slightly outside our area of expertise.

What do I think is going on here? Their legal team are scared of being sued. There have been many cases across Western Europe over the last few years of psychics using the threat of legal action to silence their critics. When it has gone to court, because the legal system so heavily supports the claimant in cases of slander or libel there is a real danger of the defendant actually losing. There was a case in Belgium or the Netherlands a couple of years back where one of Europe's first sceptical societies was ordered to take out a full-page newspaper advert saying that some psychic was actually genuine, simply because they couldn't afford to fight the case and as such disproving the claimants accusation. I'm not sure what happened, but I'd hope they'd close their doors before ever doing such a thing.

This is because here the burden of evidence in slander and libel cases is placed upon the defendant. Instead of in most other areas of law where the burden of evidence is placed upon the claimant.

In the United States you never see this happening, because the burden of evidence is placed where it belongs. It should be up to the psychics to prove they are psychic. Not the defendant to prove a negative (which is impossible).

Three things need to happen:

  • We need to change the law so the burden of evidence is correctly placed upon the claimant.
  • Watchdog also need to stop pussy footing around worrying that they'll upset the woo woo crowd.
  • All psychics, or any other practitioners of nonsense should be arrested and charged with fraud.

Julia Bradbury's bio on the BBC website mentions she's done lifestyle shows, great, the plague of television. And mentions she's coped with John Travolta (Scientology nutjob) and Arnold Schwarzenegger (right-wing Republican asshole). That's a lot of whacky stuff to fit in just one paragraph, maybe there is somebody better for the job out there.

Oh wait, one last thing I'd like to see happen as I've said before, put the BBC under the control of Patrick Moore, Richard Dawkins and David Attenborough. The BBC needs to raise its game, it needs to stop the dumbing down of its science shows and get rid of every ounce of woo woo in the rest of its programming.

Questions for "Evolutionists"

Update: This is part of a fairly long series now, click here for the full list of articles in this series.

Questions for Evolutionists, whatever an evolutionist is, from Mr Kent Hovind. I'll just go and find a biologist to tackle his attempt at disproving evolution by natural selection.

Oh wait hang on...

1. Where did the space for the universe come from?

That sounds like a cosmology question Kent. The universe doesn't displace anything, and as such requires no space. The universe creates its own space, which it is still doing at an increasing rate even today.

2. Where did matter come from?

The matter condensed out of the energy of the Big Bang, after inflation the matter in the universe was a mix of quarks and gluons. At 1.0 × 10-6 seconds after the Big Bang they formed protons and neutrons.

3. Where did the laws of the universe come from (gravity, inertia, etc.)?

The laws of nature are inherit to the universe, they were created at the Big Bang.

4. How did matter get so perfectly organized?

I don't accept the premise that matter is perfectly organised.

5. Where did the energy come from to do all the organizing?

Actually it was the energy of the Big Bang that kept atoms from forming, the temperature and density of the universe had to decrease before quarks and gluons could form baryons (protons and neutrons). They were literally too energetic whizzing around too fast for the nuclear forces to have any impact.

More of his silly questions to come at a later date, maybe he could get onto biology.

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