Category Archives: Climate

Volcanism and sea level fall

If there were decompression melting of magma in the West Antarctic volcanic province as the icesheet thinned, that would not be good news.

If the geological Society link in the article doesn’t work for you, try this one; http://sp.lyellcollection.org/content/early/2017/05/26/SP461.7

Most volcanic activity stems from the rise of hot, deep rock, usually within the mantle. Pressure suppresses partial melting, so as hot rock rises the greater the chance that it will begin to melt without any rise in its temperature. That is the reason why mantle plumes are associated with many volcanic centres within plates. Extension at oceanic ridges allows upper mantle to rise in linear belts below rift systems giving rise to shallow partial melting, mid-ocean ridge basalts and sea-floor spreading. These aren’t the only processes that can reduce pressure to induce such decompression melting; any means of uplift will do, provided the rate of uplift exceeds the rate of cooling at depth. As well as tectonic uplift and erosion, melting of thick ice sheets and major falls in sea level may result in unloading of the lithosphere.

During Messinian Stage of the late Miocene up to 3 km…

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How do we know where the carbon is coming from?

Keeling curve

Keeling curve vs prediction based on fossil fuel origin (from Scripps)

In 1957, Charles Keeling of Scripps Institution of Oceanography began regular measurements of carbon dioxide concentration at Mauna Loa, Hawaii. By 1960, he was already in a position to report a steady increase, together with seasonal variations. In the northern atmosphere, CO2 concentration falls during the spring and summer growing season, but recovers during autumn and winter as vegetable matter decays. This sawtooth pattern is superposed, however, on a steady overall increase.

The Keeling curve and beyond

Scripps Institution of Oceanography

Scripps Institution of Oceanography, from Birch Aquarium ((Invertzoo via Wikipedia)

Charles Keeling died in 2005, but the work is being continued by his son Ralph. When I visited Scripps in 1995, I saw Charles Keeling’s original curve, ink on graph paper, on the wall in the corridor outside his office. That curve has now been designated a National Historic Chemical Landmark, and there are commemorative plaques both at Scripps and at the Mauna Loa Observatory. Charles Keeling’s original paper, freely available here, goes into meticulous detail regarding sample collection, calibration, precautions taken to prevent local contamination, and comparisons between the Mauna Loa data and those that numerous other sites, including the Antarctic and samples collected from an aircraft.

By 1985, the record had been extended backwards in time by analysis of air bubbles trapped in ice cores, with dates ranging from the 1980s to the 1600s and earlier. These dates overlap Keeling’s data, and take us back to pre-industrial times. Before long, the ice core record had been extended to an 160,000 years, taking us into the Ice Ages, while further work has pushed it back to 800,000 years. We have estimates going back far beyond that, but employing indirect methods and with higher uncertainty.

Ice core record

Atmospheric CO2, 1700 – 2014; NASA via Forbes. Click to enlarge. Note that the zigzags for atmospheric data are not error bars, but annual fluctuations.

During the Ice Ages, carbon dioxide played a dual role, as product and as agent. The temperature oscillations at this time were driven primarily by subtle changes in the Earth’s motion (so-called Milankovitch cycles). But carbon dioxide is less soluble at higher temperatures (which is why your carbonated drink fizzes inside your mouth). And so in the first place the rise and fall of temperature led to a rise and fall of carbon dioxide in the atmosphere, as the oceans released and reabsorbed the gas. But then, the changes in carbon dioxide concentration amplified the original effect, since more carbon dioxide acting as a greenhouse gas makes the Earth lose heat less efficiently into space.

To summarise the results, current levels of CO2 are the highest they have been for over twenty million years. In the centuries leading up to 1800, Read the rest of this entry

Science matters because it works (but it’s not quite that simple)

Reblogged from The Logic of Science, but with this comment: No one would disagree with these claims on behalf of science, and and that’s the problem.

The climate change denialists, like the smoking science denialists before them, pretend that the science is unsettled. The creationists prattle of “creation science” and “flood geology”. The extremely able and intelligent US Vice President, pandering to his creationist base, did not claim to be anti-science. On the contrary, he used the very fact of a major scientific discovery (Sahelanthropus, evolution, and the word “theory”; what Mike Pence really said) to blur the distinction between the established core and the fast-changing frontiers. And if we are to effectively defend science, we need to understand the emotional appeal of the ideology that leads to the rejection of vaccination, medicines, and GMOs, and to the prejudging of complex arguments in such cases as fracking and nuclear power.*

We need to think very carefully about tactics. If we seem to be saying anything like “Science is a good thing, therefore you should trust the scientists”, we are playing into the hands of our enemies. We are right to demonstrate and protest when science is denied, or ignored,  or muzzled.  And yet people (that’s all of us) believe what they want to believe.  The task  then is, how to persuade people to want to believe  in the evidence?

*This last comment cuts both ways, of course

The Logic of Science

Why should you support science? Because it works! It’s crazy to me that I even have to say that, but this is where we are as a society. Various forms and degrees of science denial are running rampant throughout our culture, and attacks on science are being disseminated from the highest levels. Indeed, it has gotten to the point that hundreds of thousands of scientists and science enthusiasts like myself feel compelled to take to the streets to march for science and remind everyone of the fundamental fact that science works and is unparalleled in its ability to inform us about reality and improve our world.

Image via the CDC

Just look around you. Everything that you see was brought to you by science. The batteries that power your electronic devices are a result of scientific advances in chemistry, as are the plastics that make up seemingly everything in our…

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Reality imitates satire; smoking, climate change, and EPA chief Scott Pruitt

Jim (seated) consults Sir Humphrey

Wishing, as I recall, to evade the scientific consensus on smoking and lung cancer, Yes Minister‘s Jim Hacker turned for advice to his Civil Servant Sir Humphrey Appleby. The conversaton went something like this (I would be glad of a link to the exact transcript):

Sir Humphrey: Say the scientists disagree. Say that more research is needed.

Jim: But I thought the science was settled …

Sir Humphrey: Those scientists are always disagreeing about something, and there is  always a need for more research.

Now this, from Science magazine’s online website: Read the rest of this entry

Not waving but drowning

Adventures in the Anthropocene

Not all the news is bad; but strange times, when we have to welcome leadership from China.

Wandering Gaia is Gaia Vince, author of the award-winning Adventures in the Anthropocene, part of the emerging literature that welcomes the challenge of positively managing the planet.

 

See also Scientists’ March on Washington and Geneticist launches bid for US Senate

Wandering Gaia

If, like me, you wake everyday with a stone of foreboding in your belly, check the news to discover the world is a little worse, and stumble through your day under the heaviest pall of despair, then you’re not having the best 2017 either – I’m sorry.

Is this a new Dark Ages, this deliberate political, cultural, societal regression?

I’m sure there have been a thousand analyses of how we got into this darkly farcical horror show – and I mean the Trump presidency and Brexit disasters specifically, rather than the continuing awfulness happening to people Yemen, Syria, Nigeria, etc etc – but to be honest, one of my few comforts at the moment is my social bubble made up of kind, intelligent people who are also appalled by this new “post-fact”, mean era.

So what hope, can I give? And, yes, there is always hope!

Even though these recent…

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My fellow ex-pat Americans … easy link to register

global_temperature_anomaly-svgYes, I am a US citizen, and right now this is a responsibility that I feel I must take seriously.

One US political party, from its Presidential candiate on down, is dedicated to the denial of global warming and the headlong exploitation of fossil fuels. For me, this issue eclipses all others.

I therefore urge you: if you think that global warming is not a problem, and that fossil fuels should be exploited as fully and as quickly as possible, vote Republican.

If you think otherwse, vote Democrat.

But vote. Here’s the link. The form will take no longer to fill out than it took you to read this: https://secure.avaaz.org/en/globalvote_ph/?aAcyEab

Transgender bathrooms, creationism, climate change denial, and the Ten Commandments

Toilet signs

Toilet signs, Ebay

Why does North Carolina want to force transgender persons to use the wrong public toilet? Why the steady stream of foredoomed bills demanding evenhanded treatment of evolution and creationism? And why endless attempts to mount official displays of the Ten Commandments, when such displays have repeatedly been ruled to breach the wall between Church and State?

Toilet etiquette is where prudery meets absurdity. Your chance of being embarrassed, let alone molested, by a transgender person in a US public toilet is probably zero, and certainly less than your chance of being shot dead at home by a toddler playing with a gun; after all, the only public display of genitalia is at the men’s urinal, and you can always use a booth if you prefer.

(It is said that an undergrad once asked Sir John Pentland Mahaffy, Provost of Trinity College Dublin, where he might find a lavatory. “At the end of the corridor,” Mahaffy grandly gestured, “you will find a door marked GENTLEMEN; but don’t let that stop you.” In the UK, of which Dublin was still part at the time, class trumps gender. Incidentally, Trinity had been admitting female undergraduates since 1903, 74 years before Harvard; I assume that sanitary arrangements were instituted to cope with this.)

It is established law in the US that the teaching of creationism serves a religious, rather than scientific or educational, purpose. It follows (Edwards v. Aguillard) that such teaching is unconstitutional in US public schools, since it violates the First Amendment separation of Church and State. There is no prospect of this ruling being overturned, unless we ever get a US Supreme Court packed by a creationist President.

It has also been repeatedly established that display of the Ten Commandments on State government property violates the US Constitution, for much the same reasons.

So why do we have States bringing in transgender bathroom laws, scientifically baseless (as discussed here by my friend Faye Flam), whose only effect would be to inconvenience and offend one particular small minority? Why did this monumental non-issue even spill over into the moronic drivelfest of the Republican Party’s nomination debate? Or attract so much attention that Pres. Obama’s statement of the obvious on the subject has been hailed as “historic”?

Why do we have a whole evolving family of “sound science teaching” bills, which would single out evolution, together with climate change, as subjects concerning which students should be taught “both sides”, or the “strengths and weaknesses” of what is in fact well established science?

And why should the current Chief Justice of the Alabama Supreme Court keep on asserting his right to display the Ten Commandments in his courthouse? Does he really think it necessary to inform litigants that God brought them out of Egypt, wants them to be nice to their parents, and disapproves of graven images?

Stupidity? No, strategy. And a strategy that is highly evolved, if not indeed intelligently designed.

Consider how much these issues have in common. For a start, there is nostalgia for an imagined era of moral clarity and biblical belief. This feeds in to what is, I suspect, the most powerful of all political motivators, namely the sense of identity. We think as we do and vote as we do because of the kind of person we think we are, or at any rate would like to be. And these three issues translate as assertions of a very American kind of Christian identity. As a corollary, they define an enemy; the smug Liberal sneering at those who disagree with him (would that this image lacked validity). They are timeless, unlike the real issues of foreign policy and budgets; they will still be with us ten budget cycles and three foreign entanglements down the road.

And they work as attention grabbers, and as group identifiers. The major US retail chain Target thought it worthwhile to issue a statement inviting people to use the toilets fitting their self-description rather than their birth certificates; in retaliation, a group calling itself the American Family Association has launched a boycott petition that has gathered, so far, over 850,000 signatures. I do not know what evils the AFA plan to blame on Target, but they are among those who blame Darwin for Hitler, so they’ll think of something. AFA regards calls to action on climate change as impious, since the planet is in God’s hands. It also defends public display of the Ten Commandments, on the grounds that “the Ten Commandments are the basis of all of our laws.” These views form an identity cluster, and the inclusion of climate change denial is no accident.

deadcrabs

Crabs washed up on a beach in Oregon after suffocating in low-oxygen waters. Credit: Elizabeth Gates, courtesy of PISCO, via NSF (click to magnify)

And finally, by the same token, they are perfect distractions from reality. American readers, at least, could hardly have failed to notice the transgender toilet controversy. But how many of us are even aware of evidence published earlier this month that warming is already reducing the availability of oxygen in the oceans, and that this effect will probably be widespread by the 2030s?

We could be talking about the erosion of democracy, looming water shortages in the US and Asia, the unstable world banking system, climate change, and the facts of economic inequality. Or we could be talking about who is allowed to use which bathroom. If you were a North Carolina legislator, which would you prefer?

Mahaffey anecdote from Sorenson h/t Abbas Raza. An earlier version of this piece appeared in 3 Quarks Daily.

Professor David MacKay and the Renewables Delusion

I too would like to simply replace fossil fuels with renewables, but nature doesn’t care about what you or I would like, and renewables don’t have enough power per unit area. If you think you can phase out fossil fuels in densely populated countries without phasing in nuclear, please show me your arithmetic. David Mackay’s full book and 10 page synopsis are available (in English and several other languages) here (free download)

[See however https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/511939/Renewables.pdf (h/t Michael Reiss); renewables according to this source already generate 24% of the UK’s electricity requirements; not of course the same as total energy requirements, but not negligible either]

h/t Michael Roberts

Skepteco

“I’m not pro-nuclear- just pro-arithmetic”.

The cause for a rational evidence-based approach to energy policy has suffered a huge loss with the death of Professor David Mackay  three weeks ago, on April 14th.

Mackay, Chief Scientific Advisor at the UK government’s Department of Energy and Climate Change, was the author of Sustainable Energy Without Hot Air, a key text that has been my number one stop to point folks to as a starting point for understanding energy supply and demand. In particular, I have frequently cited this table which explains very well the limitations of wind and solar energy due to their relatively low energy density:

Power per unit land or water area

Based on these figures, population and current energy demand, MacKay calculates that Britain cannot live on its own renewables- they simply need too much land.

By contrast to the 2-20W/m2 that can be achieved through wind or solar pv power, fossil fuels or…

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The reasons for the floods

Floods are inevitable. But the degree of damage that we are seeing today is the result of reckless cuts, perverse subsidies, and mindless deregulation.

First, a review of “savings” (that’s NewSpeak for “cuts”) on flood defences:Well, Labour would say that, wouldn’t they? But @LabourEoin gives fuller links; for instance, the last set of numbers comes from House of Commons Library Note “Flood spending in England”, SN/SC/5755, 19 November 2014.

Well, maybe the Government have learned better? Then why are they cutting 6700 firefighters, who are among first responders and prevention workers in floods?

Well, maybe it is necessary to save money? It would be difficult to think of a more expensive way of saving, where every £ saved costs somewhere between £6 and £24, depending on which estimate you accept. Even if you accept government forecasts of future flood damage as accurate estimates, it makes no sense that

Under the new rules brought in three years ago, the Department for Environment Food And Rural Affairs (Defra) wanted to see an average of £8 of damage avoided for every £1 they would spend on schemes.

Previously, projects were simply expected to deliver more than £1 of damage avoided for every £1 spent, with an average across all schemes of £5 of damage avoided for every £1 spent.

(Source: Rowena Mason in Guardian, commenting  on the Somerset Levels floods, in 2014; h/t Jonathan Minton)

But aren’t things like this terribly rare? In that case, why do they happen so often? As Nassim Nichoas Taleb has pointed out (and become extremely rich by acting on his own insight) extremely rare events are more common than you think. That’s because we form our expectations from the commonplace, constructing something like a bell curve of expectations based on the fluctuations that happen all the time, but rare events can also arise from rare combinations of circumstances. Five year floods can be expected to happen every five years or so, butwe have little experience of the statistics of hundred year floods, and they may well happen much more often than once every hundred years.

[Update: for more on the frequency of “100 year floods”, and of ministerial obliviousness to explicit warnings, see here]

But can the Government be blamed for natural disaster? Yes, when its policies have directly and foreseeably contributed to it. See this from George Monbiot, in January 2014:

“Drowning in money: the untold story of the crazy public spending that makes flooding inevitable”

And this in February 2014:

“How we ended up paying farmers to flood our homes”

Or very recently (29 December 2015) this:

“This flood was not only foretold – it was publicly subsidised” (which – Scottish friends note – mentions grouse moors)

(And more in the same vein; Google Monbiot Flooding Guardian and you will see the case argued, consistently and coherently, again and again.)

Not only is this Government cutting back disastrously on flood protection at the very time when climate change is increasing risk; it is spending lavishly on policies that help make sure that those floods will be as damaging as possible. The challenge of flooding is unavoidable, but the degree of disaster is man-made.

The evolution of creationism; Kitzmiller 10 years on

December 20th is the tenth anniversary of the delivery of judgement in Kitzmiller v. Dover, an important anniversary for proponents of evolution science, and Nick Matzke, who coordinated the National Center for Science Education’s efforts at that trial, has celebrated it in the most appropriate possible manner. He has applied the methods of evolutionary tree building to the development of creationism itself in the intervening decade. The results are alarming.

Matzke_Figure

Phylogenetic relationships among creationism bills , courtesy Nick Matzke. AFA Academic freedom Act, SEA Science Education Act, further identification by year, State, and bill number

The case arose when Tammy Kitzmiller and the other parents challenged the decision of Dover Area School District Board to introduce the Intelligent Design pseudotext Of Pandas and People to their High School, along with a statement urging students to retain an open mind about Intelligent design as an alternative to Darwin’s theory”. Since the matter has been extensively discussed by me and numerous others, I will simply say that Pandas was an incoherent attack on evolution science, full of factual and logical errors, and that the statement to be read misdescribed evolution as a theory about the origin of life, and claimed that since it was a theory it was uncertain, and, moreover, that there were gaps missing from it. Drafts subpoenaed for the trial also showed that the text had originally referred to “creation science”, being hastily modified when an earlier case established that “creation science” was simply another name for religious creationism.

The case is significant as a test of the creationist claim that Intelligent Design is not a form of religious creationism, but, on the contrary, legitimate science. Judge Jones’s magnificent rejection of this claim runs to 139 legal pages; in brief, he found that this claim was baseless, the textbook error laden, the Designer no other than Christian God (in whom, incidentally, Judge Jones believes), and the arguments offered as evidence for Design scientifically worthless. For this and other reasons, he declared ID to be “a religious view, a mere re-labeling of creationism, and not a scientific theory.” It followed, under the Establishment Clause of the First Amendment of the United States Constitution, that it should not be taught in any publicly funded school. Strictly, Judge Jones’s ruling is only binding in the Middle Circuit of the State of Pennsylvania, but such is the force of its arguments that I do not imagine any challenge elsewhere, unless the US Supreme Court at some future time falls into the hands of creationists.

The creationist response has been to seek yet another, less easily penetrated, form of disguise for their activities. Instead of promoting clearly defined positions, which could be subjected to legal scrutiny, they now speak of teaching the controversy, and put forward so-called Academic Freedom Bills, which invite critical examination of evolution. Who, after all, is opposed to freedom? Shouldn’t students be aware of controversy? And why should evolution be shielded from critical examination? Scientifically speaking, of course, there is no controversy, and neither teachers nor students require special legislative permission before critically examining any concept. So the purpose is, clearly, to provide a figleaf for those who want to claim that the basic concepts of evolution are uncertain, or that creationism provides a worthy alternative.

We have had, in the past decade, 71 of these Academic Freedom Bills introduced, in 16 separate states, and passed into law in 3, while the strategy has evolved as the creationist community has learned from its successes and failures. Matzke’s achievement has been to map this evolution. I imagine no one better qualified. He was the lead member of the National Center for Science Education teisam at the trial. Since then, he has attained a Ph.D. at University of California Berkeley, and spent two years as a post-doc at the National Institute for Mathematical and Biological Synthesis (NIMBioS), housed at the University of Tennessee. He is now recognised as a rising star in his field; a Discovery Early Career Researcher Award Fellow at the Australian National University and the author of some 30 scientific papers on topics related to evolution, with attention also to science education, and to the human impact on the environment.

Matzke has special expertise in molecular phylogeny, the technique by which differences in DNA are used to construct family trees. The basic principle is simple; that a mutation that became established in one species will, unless eliminated by chance, be found in its descendants. We can use such shared mutations to pick out groups of more closely related species, and the family relationships established in this way generally show excellent agreement with the relationships established long since on the basis of anatomical homologies and the fossil record.[1]

Not surprisingly, we can apply the same principle to manuscripts, and Dennis Venema, one of my favourite writers on evolution, has compared the two kinds of application in his series of articles, Genomes as Ancient Texts. But what did surprise me was to learn that the method was applied to mediaeval legal documents as early as 1827, although now texts are examined using programs and criteria of the same kind as those in use to establish DNA phylogenies (see Phylomemetics – Evolutionary Analysis beyond the Gene, free download here). Similar reasoning has been applied to languages since 1850, and both Charles Lyell and Charles Darwin drew attention to the similarities between biological and linguistic evolutionary trees.

What Matzke has now done is to apply the principle to the content of the antievolution bills discussed above. Unfortunately, the paper in which he presents his findings, in the prestigious journal Science, is behind a pay wall, although the National Center for Science Education has published a summary, and NIMBioS has put out a very informative press release, with further accounts in Scientific American podcasts, the Washington Post, and the media company Vocativ.

Anyway, here is what he says, and why it matters.

We can construct a family tree for these antiscience bills. Until around 2006, they were described as Academic Freedom Acts and discuss the teaching of evolution and the origin of life. (Logically, this is a total muddle, since biological evolution does not address the origins of life, any more than chemistry addresses the origin of atoms. Rhetorically, though, it’s a smart move. Creationists often accuse biology teachers of presenting as fact highly speculative theories regarding the origins of life, and although it is decades since biology textbooks did this, mud sticks.) In 2006, an extremely alarming development took place. Ouachita Parish, Louisiana (a Louisiana Parish is much the same thing as a County in other States) developed a policy, in what they renamed a Science Education Act, that lumped together evolution, the origins of life, global warming, and human cloning. The mention of human cloning is purely for effect; we are, and I hope we will choose to remain, a long way from being able to do any such thing, and if we do it will not be in the school science lab. However, it rightly raises alarm.

One truly insidious development is the addition of global warming to the mix. In the US, although not in the UK, the doctrinally conservatism that leaves to creationism is associated with extreme political conservatism, a deep devotion to free markets and suspicion of government, and rejection of the science of global warming, because it implies the need for government (and, worse, inter-government) action. Thus there is an excellent correlation, in the US, between evolution rejection by various faith groups and climate change rejection. Since the fall from power of Tony Abbott in Australia, the United States is I believe the only nation in which one major political party denies that global temperatures are rising, and that fossil fuel burning is responsible. Thus we have the embarrassing spectacle of scientifically illiterate congressmen holding hearings to which they invite cranks and outliers, and doing all they can to sabotage the outline climate agreement recently reached in Paris. As I have said here before, evolution denial is ridiculous but climate change denial is dangerous.

Even more worrying to me is the spread of voucher systems, under which the local government does not run the education system itself, but issues vouchers to all eligible schoolchildren, to pay for their education by non-government schools. MSNBC reports that there are hundreds of such schools teaching creationism as a taxpayer’s expense in nine States and the District of Columbia.

And worst of all is the fact that creationism happens because people want it to. Which means in turn that often there is no effective opposition, either in the community or in the classroom. According to an article in Science, Defeating Creationism in the Courtroom, But Not in the Classroom (2011, 331:404, paywall), timed to roughly match the 5th anniversary of Kitzmiller, around 11% of US biology teachers actually teach creationism, 28% teach evolution according to guidelines, and the remaining 60% avoid the topic because they do not feel prepared to deal with the hostile questioning that it will evoke. Top down imposition of evolution may, alas, be necessary, but it is certainly not sufficient.

Comic relief time: This work has not received universal approbation. At the mendaciously mistitled Evolution News and Views, no less a person than John G. West, political scientist, acolyte of C. S. Lewis, and Vice President of the Discovery Institute, goes to the heart of the matter:

Did Nick Matzke Misuse National Science Foundation Money Intended to Fund Science Research?

Professor West has done us all the great service of looking up the grants that funded Matzke during this work. One of them, he reveals, was earmarked for studying the phylogeny of shellfish. But creationists are not shellfish, so Nick has been very, very naughty. This is not the first time that Discovery Institute fellows have found it necessary to rebuke him. Casey Luskin has pointed out that he is known to have actually received money from the National Center for Science Education (he was employed by them at the time), so no wonder he supports evolution. And two days later David Berlinski criticised him for criticising Stephen Meyer for not using cladistics, because Berlinski thinks you shouldn’t use cladistics, because if you imagine that a cladogram is a geometrical, rather than merely a topological, representation, you can get the wrong answer. (As it happens, the only time I have met this mistake is in the pages of Of Pandas and People, which is roughly where we came in). You can find the whole shocking story here, and I hope that Nick takes these lessons to heart.

1] In the case of biological species, things can get a little more complicated, if only because we are dealing with interbreeding groups, within which genetic material is duplicated and shuffled, rather than unique copies. So species can split while still carrying more than one version of a gene. For example, the genes coding for Type A and Type B blood groups arose by mutation from a common ancestor, at some time more remote than the common ancestor of humans and chimpanzees, and both types were present on both sides of the chimp-human split. Thus a human with blood type A will, with respect to just that single gene, be more closely related to a chimp with the homologous blood type than to a human of blood type B. For this reason, all evolutionary trees are fuzzy. There is also the matter of horizontal transfer, in both biological and meme evoultion.

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