Donald Prothero’s Imaginary Evidence for Evolution (yet another evo hoax!)

That’s the lesson of Donald Prothero’s book, Evolution: What the Fossils Say and Why It Matters (New York: Columbia University Press, 2007). Prothero is a professor of geology at Occidental College in Los Angeles. On November 30, he teamed up with atheist Michael Shermer (founding publisher of Skeptic Magazine) to debate Stephen Meyer and Richard Sternberg of the Discovery Institute.

Shermer wrote the foreword to Prothero’s book, calling it “the best book ever written on the subject.” In fact, “Don’s visual presentation of the fossil and genetic evidence for evolution is so unmistakably powerful that I venture to say that no one could read this book and still deny the reality of evolution.”

Of course, “evolution” can mean many things, most of which nobody would deny even without Prothero’s book. For example, evolution can mean simply change over time, or minor changes in existing species (“microevolution”), neither of which any sane person doubts. Both Shermer and Prothero, however, make it clear that by “evolution” they mean Darwin’s theory that all living things are descended from a common ancestor, modified principally by natural selection acting on unguided variations (“macroevolution”).

The modern version of the theory asserts that new variations originate in genetic mutations. Some of the most dramatic mutations occur in “Hox genes,” which can determine which appendages develop in various parts of the body. On page 101 of his book, Prothero shows pictures of two Hox gene mutations: “antennapedia,” which causes a fruit fly to sprout legs instead of antennae from its head, and “ultrabithorax,” which causes a fruit fly to develop a second pair of wings from it midsection. But both of these are harmful: A fruit fly with legs sticking out of its head is at an obvious disadvantage, and a four-winged fruit fly has no flight muscles in its extra pair of wings, so it has trouble flying and mating. Both mutants can survive only in the laboratory; in the wild they would quickly be eliminated by natural selection.

Some Darwinists have suggested that ancestral four-winged fruit flies could have evolved by mutation into modern two-winged fruit flies. But this explanation doesn’t work, because a two-winged fly hasn’t simply lost a pair of wings; it has acquired a large and complex gene (ultrabithorax) that enables it to develop “halteres,” or balancers. The halteres are located behind the fly’s normal pair of wings and vibrate rapidly to stabilize the insect in flight. So the two-winged fly represents the gain—not loss—of an important structure. (See Chapter 9 of my book Icons of Evolution).

Prothero ignores the evidence and suggests that ancestral four-winged flies simply mutated into modern two-winged flies. Modern four-winged mutants, he writes on page 101, “have apparently changed their regulatory genes so that ancestral wings appeared instead of halteres.”

Not only does Prothero ignore the evidence from developmental genetics, but he also invents an imaginary animal to complete the story he wants us to believe. Page 195 of his book carries an illustration of an eighteen-winged dragonfly next to a normal four-winged dragonfly, with the following caption: “The evolutionary mechanism by which Hox genes allow arthropods to make drastic changes in their number and arrangement of segments and appendages, producing macroevolutionary changes with a few simple mutations.”

Yet there is no evidence that eighteen-winged dragonflies ever existed. There are lots of dragonflies in the fossil record, but none of them remotely resemble this fictitious creature.

No matter. In what Michael Shermer calls “the best book ever written on the subject,” Donald Prothero simply makes up whatever evidence he wants.

Well my initial comment was pointing out the different biological mechanisms behind Heliotropism and Geotropism.

I don't recall saying you were wrong, other than pointing out that “towards the Sun” isn't a constant direction; it is variable. And heliotropism isn't keeping the entire plant moving in one direction, it is twisting the leaves so that they face east in the AM and west in the PM.

And yes, if you put a grow light to the left of a plant, it will display Phototropism and grow (its stems) towards the light and to the left.

If you track the light from one side to the other over the course of a 12 hour period, the stems will still be growing towards the left due to its initial Phototropism; but its leaves will track the light as it moves because its (leftward growing) stems will twist to keep the leaves facing the light; this is Heliotropism.

If you move the light from the left of the plant to the right, its stems will start growing in the other direction and it will look like one confused plant!

Phototropism will point the plant stem/wood structure in the direction where it is getting the most sunlight; and Heliotropism will point the leaves towards the sun by causing the stems to twist through hydraulic pressure.

So I guess Phototropism is the long term strategy of growing the entire plant structure towards the sunlight; while Heliotropism is the day to day tactic of facing your leaves to the sunlight.

I.E. Plants and trees grow towards the maximum source of sunlight (following it by maintaining an average position with respect to it’s daily movement).

If the source of light is rigid, they grow straight for it.

The plant’s ability to use (or need to use) is likely miniscule, and may only be used in a very brief period when it is underground.

A seed sprouts due to moisture and temperature (change). The temperature change is a direct result of sunlight. The sprouting seed pursues the source of that warmth to reach the surface. In that case it may be following infra-red rather than visible solar.

The use of ‘gravity’ to determine direction of growth is an unproven theory, and seems to have very little effect compared to the source of heat and light.

If you can point me to a documented source which can prove that seeds use ‘gravity’ to determine direction, I would be glad to read it.

By detecting “down” the plant also will know the direction of “up”.

It uses those starch statoliths to determine which direction it is going to send up its cotyledons. IIRC they did some trick with the starch statoliths to confuse the plant, and it sent shoots the wrong way. This gravotropism is also why NASA scientists were interested in sprouting seeds in zero gravity.

If you have a hypothesis about infra-red detection, we need an experiment, and data to support that; then find your mechanism and the signaling pathways. Or if the work has already been done you need a good reference to it.

Gravotropism has the hypothesis, the experiment, the data that supports it, as well as a known mechanism. I am unaware of the exact signaling pathways, but no doubt some sort of cascade of phosphorylations or some such modifying proteins, transcribing different genes, etc. Plant cells are often interconnected via cytoplasm, so signals are regional and often need no specific inter-cellular mechanism.

No, a seed is NOT ‘intelligent’.

A seed is capable of carrying out a biological program of expressing particular genes, devoting resources, and detecting directionality such that the cotyledons grow “up” because the start statholites settled “down”.

Directionality is established by the starch particles. Up and down are opposite sides of the same coin. If a plant can detect ‘down’ then the program has established (by which I mean “know”) which direction is ‘up’.

Gravitropism is just used to grow the cotyledons ‘up’ as far as I know, but like I said - one botany class, long ago; used to skip it sometimes for a midafternoon break with my girlfriend who didn't have class at that time.... pretty little thing.

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