This morning "In our Time" Melvyn Bragg and his guests discussed the geological formation of Britain. You can download the podcast from this link. They inevitably touched on plate tectonics
As I was listening to it, I wondered just what the 40% of Americans who believe in the literal truth of the Bible-"young age creationists"- would make of this. They believe that the earth is about 6,000 years old.
We have teachers in Britain who believe the same. Nick Cowan is a science teacher at the Bluecoat School in Liverpool. Watch him in discussion with Richard Dawkins,
and ask yourself- would you like Mr Cowan teaching your kids science?
Back to plate tectonics.
Just how do creationists of the young age variety, like Cowen, work out how the continents turned out as they did?
They accept the continents have moved over time, but they think it happened during the 40 days and nights during which Noah, his family and all the animals, presumably including dinosaurs and monkeys, were aboard the Arc. Everything must have happened at high speed.
Richard Dawkins in his "Greatest Show on Earth" has done the sums for us. South America and Africa sped away from each other faster than a man can swim-for 40 days and nights.
This morning, Today Programme allowed the World Cancer Research Fund (WCRF) to peddle the link between processed meat, sausages, bacon, salami and ham, and colorectal cancer. You can listen to the interview here.
Over a year ago, the Daily Telegraph reported it with this a scary headline " sausage a day can increase bowel cancer risk"
This morning, Lisa Cooney, the head of education at the WCRF, asserted " there is convincing scientific evidence linking the consumption of processed meat with an increased risk of bowel cancer". The hapless Evan Davis accepted this assertion and moved on.
Ok, there's a lot of statistics in there, but my O level maths didn't let me down.
Colquhoun's piece starts with this challenge to the WCRF report.
..... there has never been a randomised trial to test the
carcinogenicity of bacon, so it seems reasonable to ask how strong is
the evidence that you shouldn’t eat it? It turns out to be
He then asks the relevant question. Is there a causal link between the consumption of processed meat and colorectal cancer? If there is no such link, then why are the WCRF telling us not to eat bacon and sausages?
In the case of sausages and bacon, suppose that there is a correlation
between eating them and developing colorectal cancer. How do we know
that it was eating the bacon that caused the cancer – that the
relationship is causal? The answer is that there is no way to be sure
if we have simply observed the association. It could always be that
the sort of people who eat bacon are also the sort of people who get
colorectal cancer. But the question of causality is absolutely
crucial, because if it is not causal, then stopping eating bacon won’t
reduce your risk of cancer. The recommendation to avoid all processed
meat in the WCRF report (2007) is sensible only if the relationship is causal. Barker Bausell said
[Page39] “But why should non scientists care one iota about
something as esoteric as causal inference? I believe that the answer to
this question is because the making of causal inferences is part of our
job description as Homo Sapiens.”
That should be the mantra of every health journalist, and every newspaper reader.
Colquhoun then goes on to examine in detail the studies relied on by the WCRF paper and concludes.
After all this, we can return to the original question. Do sausages or
bacon give you colorectal cancer? The answer, sadly, is that nobody
really knows. I do know that, on the basis of the evidence, it seems to
me to be an exaggeration to assert that “The evidence is convincing
that processed meat is a cause of bowel cancer”.
Sometimes I think we should say “I don’t know” rather more often.