Archive for the 'Evolution'

I’ve been playing with it for a while. It turns out that when you go back to Cretaceous Morris, you need to be able to swim really well, but Cambrian Morris is high and dry on a fairly small landmass (whoa, but oxygen is way down and carbon dioxide way up). You can have your own time machine, too — it’s the EarthViewer app for iPad, and it’s free from HHMI Here’s what it has: • Data and continental reconstructions dating back billions of years • Climate and carbon dioxide data for the last 100 years • The ability to manipulate the globe and zoom to any location • Track the location of modern cities back over 500 million years • In depth features on major geological and biological events in Earth history • Clickable details on geologic eons, eras, and periods • Automated play modes • An extensive reference list • Suggestions for classroom use • Tutorial videos Did I mention that it’s free? This HHMI thing is pretty danged sweet.

It’s a harsh world for us men. Oh, sure, we’ve got all the political and economic power, and we’ve got most of the guns, but step into a senior citizens’ center and you’ll notice the preponderance of elderly women. Men die younger, on average. I’m also acutely aware of the growing disparity as we get older: my wife seems to be aging at about half the rate I do. If you’ve been watching House of Cards on Netflix, you may have noticed that the character played by Kevin Spacey, face a bit puffy and deeply lined, is married to a character played by Robin Wright (Princess Buttercup!) who is looking fabulous: mature, a bit severe, but still looking great. This situation is not unusual. This is not fair. The average life expectancy of women in the US is 80 years, while men live to be about 75. Why? It’s not sufficient to say it just is that way; we have to dig deeper and figure out the differences. Part of the answer is that human males have a youthful history of riskier behavior than females, but again we have to ask why: what is driving men to do stupid stunts that lead to higher rates of mortality? But even if we have a good answer for that one, it doesn’t address that other problem, the accelerated rates of male senescence. I’ve survived my heightened risk of death by misadventure, so why am I getting increasingly decrepit while women my age are looking more fit and healthy? Part of the answer may be in your genes, your mitochondria, and evolution. Mitochondria play an extremely important set of roles in aging. They hold the keys to cell death and responses to cancer; most apoptotic responses are triggered by the release of signals from the mitochondria. Mitochondria are the agents that produce energy for the cell, and also produce reactive oxygen species in their normal operation. You may be hearing the hype about anti-oxidants, and are diligently taking cofactors and vitamin pills to reduce,...
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I have a bit of a peeve with a common analogy for the human genome: that it is the blueprint of the body, and that we can find a mapping of genes to details of our morphological organization. It’s annoying because even respectable institutions, like the National Human Genome Research Institute, use it as a shortcut in public relations material. And it is so wrong. There is no blueprint, no map. That’s not how the system works. What you actually find in the genome are coding genes that produce proteins, coupled to regulatory elements that switch the coding genes off and on using a kind of sophisticated boolean logic. Each cell carries this complex collection of regulated genes independently and identically, but the boolean logic circuits produce different outputs varying with the inputs from the environment and the diverging histories of each cell. For instance, there is no code anywhere in the genome that commands the forelimbs to make five and only five digits: instead, a cascade of genes and cell movements produce a patterned tissue that in us contains sufficient mass and is of a size to generate five nuclei of condensing tissue that produce fingers. It’s better to think in terms of cellular automata. The embryo is a pool of autonomous cellular robots that have general rules for how they should respond to environmental cues…and those cues tend to vary in predictable ways across the embryo, leading to a consistent cascade of action that produces a relatively consistent complex product, the multicellular organism. The unfortunate consequence of those properties, though, is that you’ll never be able to look at a single gene from the genome and sort out what it does in the embryo. All the genes will be rather cryptic; you might be able to figure out that, for instance, the gene codes for an adhesion protein that makes the cell stick to a certain other class of cell, and that it’s switched on by gene products X and Y and...
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Another feathered dinosaur has been found in China, prompting Ken Ham to dig in his heels and issue denials. Yet another supposed “feathered dinosaur” fossil has come to light, again in China. (Dr. Elizabeth Mitchell, AiG–U.S., reported on another Chinese fossil of a supposed feathered dinosaur in April 2012) Now, one headline described the fossil as “almost birdlike,” and the authors of the report in Nature Communications note many features the fossil shares with living birds, particularly those that live on the ground. In fact, Dr. Elizabeth Mitchell and Dr. David Menton (AiG–U.S.) both examined the photos of the fossil and the criteria the authors used in classifying the fossil as a dinosaur. They agreed that it is a bird, not a feathered dinosaur. Oh, really? It’s just a bird? Take a look at this image of Eosinopteryx, and you tell me. Notice a few things about this animal: it’s got teeth. The forelimbs have clawed digits. It has a long bony tail. It lacks the bony keel that anchors breast muscles in modern birds. The only thing that might cause you to question its dinosaur nature (and it’s a criterion that’s proving more and more inappropriate) is that lovely gray fringe of feather impressions that surround the whole fossil. And look at those forelimbs! It looks like it has stubby wings. It does not, however, have the skeletal and muscular structure to allow for extended flapping flight, and the wings are way too short for it to have been an adequate flyer. But Mitchell and Menton and Ham looked at that and said ‘ALL BIRD’. They’re idiots. Ham goes on: there are no transitional forms, he squeaks, there can be no transitional forms, transitional forms don’t exist…all while looking at a winged, feathered reptile with teeth and claws and a bony tail. The fossil record doesn’t reveal any kind of dinosaur-to-bird evolution—and it certainly does not show a molecules-to-man...
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Ken Ham is preaching about what science is again. He’s accusing the secular activist Zack Kopplin of being “brainwashed” by evolutionist propaganda, and to support this claim, he once again drags out the tired proposition that there are two kinds of science, historical and observational, and that only the observational kind is valid; well, unless the historical version is based on the Bible, which in his dogma is an unassailable compendium of absolutely true facts about the past. What’s more, Kopplin—like almost all evolutionists—confuses historical science with operational (observational) science. Operational science is indeed observable, testable, falsifiable, and so on—but none of those words describes evolutionary ideas! While biblical creation may not be provable through tests and observation, neither is molecules-to-man evolution (or astronomical evolution). And in fact, the evidence that is available to us concerning our origins makes sense in the biblical creation-based worldview, not the evolutionary one. Of course, secularists mock creationists for separating out historical science and operational science. But they do that because the secularists want the word science to apply to both historical and operational science so that they can brainwash people (like Kopplin) into thinking that to believe in creation is to reject science. This is utter nonsense. It’s a phony distinction he makes so that he can bray, “Were you there?” at people and pretend that he has refuted anything they might say about the past. It is a set of appalling lies from a know-nothing hidebound fundamentalist who knows nothing about science, and who happily distorts it to contrive support for his ridiculous beliefs. It is false because of course I can observe the past. The present is the product of the past; if I open my eyes and look around me, I can see the pieces of history everywhere. I live in the American midwest. I can go into...
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