Sunday, 24 August 2014

More Manny Insanity

As regular readers will know, some two years ago I posted a challenge to a Twitter user then using the account name @Sacerdotus who had been posing as a Catholic priest in training and claiming multiple university degrees in philosophy, physics, theology, psychology - in fact almost anything you cared to mention. He had been claiming to have irrefutable, scientific proof that the Christian god existed and that no other go did, and challenging people to debate him.

After one hilarious day during which, in the small hours of the morning in the UK, he posted dozens of challenges to me, one every few seconds and then declared victory claiming I had ignored him, I decided to call his bluff and challenged him to a formal, neutral and independently refereed debate,

Thursday, 21 August 2014

Pygmies - Another Big Problem for Creationists

Baka pygmies, West Africa
African pygmies evolved their short stature twice - health - 18 August 2014 - New Scientist

A paper published in PNAS last month is interesting for what it tells us of human evolution and of evolution in general, and it raises a major question for creationist loons to carefully avoid.

Significance

Tropical rainforest hunter-gatherer populations worldwide share the pygmy phenotype, or small human body size. The evolutionary history of this phenotype is largely unknown. Here we studied DNA from the Batwa, a rainforest hunter-gatherer population from east central Africa, to identify regions of the Batwa genome that underlie the pygmy phenotype. We then performed population genomic analyses to study the evolution of these regions, including comparisons with the Baka, a west central African rainforest hunter-gatherer population. We conclude that the pygmy phenotype likely arose due to positive natural selection and that it arose possibly

Tuesday, 19 August 2014

Scientists At War!

Homo floresiensis
Scientists at war over claim that Flores hobbit man is modern human with Down's syndrome | Science | The Observer

This slightly alarming headline from the Observer leads neatly into a comparison between how scientists wage 'war' what's going on in the Middle East at the moment where theists are waging war - and happily killing one another and innocent civilians including women, children and other non-combatants as a matter of routine.

Another contrast of course is that, whereas the scientists' 'war' will undoubtedly end in agreement with almost

Sunday, 17 August 2014

Abiogenesis - The Day of Reckoning For Creationists is Nigh

Meet your maker: Homing in on the ancestor of all life - life - 12 August 2014 - New Scientist

Creationist pseudo-scientists have a problem, and not the obvious one of more and more people seeing through their deceptions, working out why they are necessary and realising a rational, scientific explanation is preferable to a magical one which requires lies and misinformation to promote it. The problem they have is, like the problem of the virtual certainty that at some point in the near future, scientists will find evidence of life on another planet, probably in another planetary system, the problem of one of their fundamental arguments being shown to be without any foundation.

I'm talking about the fact that science is getting closer

Religious Intolerance

Someone posted a question in our Why Atheism? Facebook group the other day asking which religion was the worst, especially in the context of the Middle East where the three Abrahamic religions are currently slugging it out for control of Iraq, Syria and Palestine, and in Africa where Muslims and Christians are also fighting and killing for their religions.

Looking at the history of Europe and the Middle East particularly, and later the history of European colonialism, it's probably true to say that, until 1948 the one Abrahamic religion that had generally been on the receiving end of persecution and atrocity and yet had no history of retaliation or counter atrocity was Judaism.

In fact, the contribution of Jews to European and Middle Eastern philosophy, art, politics, science, medicine,

Friday, 15 August 2014

Unintelligently Designed Fractal Ediacarans

A paper published recently in PNAS, showing how the earliest forms of multicellular life probably evolved and diversified according to a few simple mathematical rules, raises an important question for creationists which we can confidently expect them to ignore completely.

This early evolution occurred at a time when there would have been little or no cell specialisation and, perhaps more importantly, when there would have been no predators and the only competition would have been for limited resources in terms of dissolved nutrients. Quite simply, the organism which absorbed more nutrients would have produced more copies of itself.

Sunday, 10 August 2014

Human Evolution - Completing the Picture

Neanderthal family (artists impression) Photograph: Nikola Solic/Reuters
To me, watching a science grow and develop is what makes it more like an adventure than a dull, academic subject. Discoveries are made and fed into the mix; ideas and opinions are contributed by people who are experts in the field; old ideas are revised, reviewed and discarded if necessary and eventually a new consensus emerges which is, in the long run, a little closer to the truth. All the while the picture grows in clarity, sometime becoming more complex that we thought and sometimes simpler.

How unlike religion where the entire effort is devoted to excusing yet again that which is nothing more than evidence-free dogma, finding new and ever-more creative workarounds for the fact of no evidence, and inventing new ways to bamboozle a diminishing following into believing that, despite the overwhelming evidence to the contrary, and despite the enormous gains of science and its contribution to human welfare since the enlightenment, their Bronze-Age belief in magic is the best explanation of reality.

A couple interesting articles in this week's New Scientist illustrate how our knowledge of human evolution keeps being added to and our understanding of is revised and refined accordingly.

Friday, 8 August 2014

Silly Bible - Lot of Nonsense

Albrecht Dürer Lot Fleeing with his Daughters from Sodom (1498)
The biblical story of Lot is another strange tale with no obvious reason for being in the Bible, at least so far as morality tales go. In fact, it shows the god of the Hebrews in a very poor light, overly obsessed with what humans do with their genitalia but having a low regard for women and no problem at all with incest. It also portrays it as far from omniscient, unsure of what justice means and easily persuaded by a mere human but then capriciously changing its mind and killing innocent people anyway simply for being there at the time.

We also see how the person writing it had difficulty holding a thought across more than a couple of paragraphs.

I have already written about the nonsensical account of God telling Abram that he was going to destroy the cities of Sodom and Gomorrah and Abram bargaining God down from fifty to ten as the number of righteous people to be found in the cities to prevent him killing everyone, innocent or guilty.

There doesn't seem to have been any such attempt to find ten righteous men though and God sets about killing everyone anyway. To accomplish this he sends two angels to the city and they end up at Lot's house, where a mob comprising all the men of the city gather outside demanding to be allowed in to bugger the angels.

Monday, 4 August 2014

More Bible Blunders

Some time ago I wrote about Thomas Paine's debunking of the notion that the Pentateuch was written by Moses, as though supposedly writing about his own death and burial in a secret place wasn't enough. Thomas Paine, in The Age of Reason, written in 1794 showed that the Bible refuted that argument itself. First we are told in Genesis that:

And when Abram heard that his brother was taken captive, he armed his trained servants, born in his own house, three hundred and eighteen, and pursued them unto Dan.

Genesis 14:14

Then later on we discover that it wasn't actually called 'Dan' until much later; before then it was called 'Laish'.

Saturday, 2 August 2014

Parasites and Creationists


Heligmosomoides polygyrus

Photo: Janice Murray & Maizels Laboratory/University of Edinburgh
I've commented before on how parasites are a problem for creationists and, apart from their understandable shyness at discussing parasitism, this probably explains why creationist loons who misrepresent science and misinform scientifically illiterate people for a living never seem to discuss parasites or explain how they fit into an intelligent design model, especially one in which the supposed intelligent designer is omnibenevolent and created everything just for humans.

For example, the leading Discovery Institute (aka Liars For Power and Money, Inc.) propagandist for ID, Michael Behe, avoids completely any reference to the fact that his 'intelligently designed' E. coli flagellum appears to have only one purpose - helping E. coli make us sick.

With their evident discomfort in mind then, it gives me great pleasure to invite creationists to comment on an article and two papers published recently in Science concerning how infection by a parasitic worm (helminth) can appear to aid other parasites by helping them overcome the body's natural immune responses. In particular, I would like them to explain how this phenomenon is better explained by their intelligent-design-by-an-omnibenevolent-designer-who-did-it-all-for-humans model than it is by Darwinian evolution by Natural Selection.

Friday, 1 August 2014

The Incredible Shrinking Dinosaurs

Dinosaurs shrank for 50 million years to become birds - life - 31 July 2014 - New Scientist

I was surprised and more than a little disappointed to to see the angle taken in the above article. It looks almost designed to supply a handy quote for quote-mining creationist pseudo-scientists to mislead their credulous victims with.

"No other dinosaur group has undergone such a long and extended period of miniaturisation," says Mike Lee of the South Australian Museum in Adelaide. "Statistically this trend was far stronger than by chance, analogous to flipping a coin a dozen times and getting all heads."

[...]

The analysis reveals that the ancestors of birds shrank without interruption. "What was impressive was the consistency of the size change along the dinosaur-to-bird transition, with every descendant smaller than its ancestor," says Lee.

It's not till we get to the final sentence in that last paragraph that we discover there is a simple and obvious answer and one moreover which illustrates how Natural Selection makes evolution non-random.

Thursday, 31 July 2014

Origins Of The Exodus Myth


With so many to choose from, it's difficult to decide which of the various folk tales, invented 'histories' and origin myths that have found themselves bound up in the same book and presented as the inerrant word of an omnipotent god is the silliest, but one of them has to be the tale of Hebrew enslavement in Egypt and subsequent escape.

It was obviously written by someone who knew little or nothing of the geography or politics of the time and place the tale was set, so we have the idiotic notion of the 'Israelites' escaping from Egypt by crossing the Red Sea to Sinai - which was also in Egypt. That's like 'escaping' from the USA by crossing the Hudson River from New Jersey to Manhattan or escaping from the UK by crossing the Bristol channel from England to Wales. The author also has the 'slaves' building the Egyptian city of Raamses - which wasn't started until some 120 after the traditional date of the Exodus.

Killer Sperms Reinforce the Species Barrier

Killer sperm ravages internal organs of luckless worms - life - 30 July 2014 - New Scientist

I've mentioned before how, as two diverging nascent species each evolve specialisation, hybrids will often be at a disadvantage being good an neither of their parent's specialities. As isolated and diverged populations of finches came back together, at the end of the last Ice Age for example, one might have evolved a long thin beak for eating small seeds and the other a short stout beak for eating large hard seeds. A hybrid with a long stout beak or a short thin one would find feeding difficult so it would be in the interests of both sets of genes to set up barriers to interbreeding.

The very fact that they are diverging accelerates the process of speciation, not as an end in itself but to protect the advantageous genes from being wasted on hybrids which have a lower probability of passing them on (see Why Species?, Creationist's Macro-Evolution Lie and More Mimetic Evolution).

We now have a rather surprising, even shocking example of one such barrier in closely related nematode worms.

More Evolved Mimicry

This is my last blog for a while on the fascinating topic of mimicry in animals and plants. Previously I wrote about Batesian and Müllerian mimicry in Copycat Evolution and More Mimetic Evolution where a harmless species comes to resemble a harmful one and so gains protection from a predator which has learned to avoid the harmful one (Batesian), or two harmful species come to resemble one another and so gain from the evolutionary 'spade-work' of the other (Müllerian).

Now I'm going to look at another form of mimicry where (usually) a plant deceives another species into thinking it's something else, not to repel or avoid it, but to attract it. Almost invariably this improves pollen or spore distribution so it's not hard to understand how any improvement in this system gave the plant an advantage and so natural selection favoured it.

Tuesday, 29 July 2014

Murmuring Starlings Do It Naturally.

Decisions ripple through flocks of birds like a wave - physics-math - 27 July 2014 - New Scientist

One of the most spectacular sites in nature in Britain is a winter 'murmuration' of starlings, and I'm fortunate enough to live just a short drive from the open stretch of moorland north of Oxford known as the Otmoor, now a wonderful RSPB-owned nature reserve and important inland wetland site, where this spectacle can be seen most winter evenings at sunset in suitable weather.

Watch these videos first, then I'll discuss them. The first was filmed over Otmoor, the second at Gretna in Scotland.

Monday, 28 July 2014

More Mimetic Evolution

Having blogged a couple of days ago about the role of mimicry in evolution I decided to look more closely at the subject, especially the widespread mimicry found in butterflies. The results are fascinating.

But before I get on to that I'll just deal quickly with another aspect to evolution - speciation - following on from something I mentioned in the same blog. I pointed out how mimicry involved a two species both of which are prey to the same predator and where at least one of them is toxic or harmful to the predator.

I mentioned that the selection pressure for one species to become more and more like the harmful one depends on the presence of the predator in the local environment but the species range may well include areas with different predators, different comimics or indeed the absence of one or both. In this case, and in that part of the range there may be no selection pressure and no particular advantage in adopting the colour pattern of the toxic or harmful species, and there may even be a disadvantage because a different predator may not have any aversion to the mimicked colour.

Sunday, 27 July 2014

Recent Evolution - That Old Chestnut

Horse chestnut leaves infested with Cameraria ohridella lavae.
If you live in Southern England, for an example of very recent evolution you probably only need walk to your nearest horse chestnut tree. I took this photograph near Sunningwell, Oxfordshire earlier on Saturday when we went out for a last distant look at Didcot Power Station, which is probably England's best-loved 'eyesore' but which is due to disappear in a cloud of dust in a few hours time. The chances are that by now your nearest horse chestnut tree will be becoming infested with the leaf-miner caterpillars of a moth which was unknown before 1985 when the first outbreak was recorded in Macedonia, Greece.

Since then, Cameraria ohridella has spread at an average of 60 Km per year across western Europe reaching England in 2002, where it is now widespread, causing the leaves of horse chestnut trees (Aesculus hippocastanum) to turn brown, wither and fall off by late summer. Devastating though this attack appears, the general health of the trees seems not to be unduly affected since they come back into leaf and grown normally the following spring.

Although this moth was a newly-discovered species in 1985, specimens of it were accidentally collected and pressed in botanical specimens as early as 1879 only to be rediscovered when a team of researchers carried out a systematic search of specimens stored in herbaria.

Abstract
Determining the native geographic range or origin of alien invasive species is crucial to developing invasive species management strategies.

Friday, 25 July 2014

Copycat Evolution

Which ones would you pick up?
A friend asked me the other day to explain how mimicry can play a role in evolution. This is my attempt to do so.

There are in fact two main types of mimicry recognised by biologists, although the distinction is quite technical and is blurred anyway. For all practical purposes, they can both be regarded as forms of the same thing. They are known to biology as:

  • Batesian mimicry. Named after the English naturalist Henry Walter Bates. This is where a harmless species evolves to resemble a harmful species if it and the harmful species share a common predator.
  • Müllerian mimicry. Named after the German biologist Fritz Müller. This is where two harmful species evolve to resemble one another if they both share a common predator.

Thursday, 24 July 2014

Evolution Arms Race - Moose Spit Detox

Ungulate saliva inhibits a grass–endophyte mutualism

A fascinating example of both evolutionary cooperation and an evolutionary arms race was published in Royal Society Biology Letters yesterday.

Abstract*

Fungal endophytes modify plant–herbivore interactions by producing toxic alkaloids that deter herbivory. However, studies have neglected the direct effects herbivores may have on endophytes. Antifungal properties and signalling effectors in herbivore saliva suggest that evolutionary pressures may select for animals

Wednesday, 23 July 2014

Around the Bend with Ken Ham


2 January 2013: Astronomers have determined that the Milky Way may contain as many as 400 billion exoplanets, with almost every star hosting at least one planet.
"We'll find a new earth within 20 years" | Around the World with Ken Ham

Signs that Ken Ham may be beginning to panic at the thought that science could soon find evidence of life on another planet emerged recently with this desperate attempt to harness his fundamentalist audience in a bid to stop NASA looking for it, dismissing it as a waste of money which is bound to fail. His panic can be gauged from the horrible muddle he gets into with his argument where he inadvertently 'proves' that there isn't non-human life on Earth either.

He also showed his traditional propensity for making things up, even about the Bible, and relying on his ignorant audience not checking.
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