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Ready, Steady, Evolve
Stront writes "New Scientist is reporting that plants and animals can 'bottle up' evolution until they need it. A certain protein 'hides away' mutated genes acting like a genetic valet, however in extreme environments, such as high temperature or noxious chemicals, the cleaning process breaks down and the mutations are released all at once. This goes some way to explaining examples that are considered to defy standard evolutionary theory, such as the Bombardier Beetle."
Natural selection doesn't work on genes, it works on phenotypes - the expression of those genes. If a bunch of mutations are "hidden" for a time, but then suddenly expressed in a time of "need" (i.e., rapidly changing environment), selection can then do its thing.
This finding in no way goes against natural selection.
Well, since you don't want to (can't?) read the article linked to above before criticizing, I'll quote it for you.
Quinones are produced by epidermal cells for tanning the cuticle. This exists commonly in arthropods. [Dettner, 1987]
Some of the quinones don't get used up, but sit on the epidermis, making the arthropod distasteful. (Quinones are used as defensive secretions in a variety of modern arthropods, from beetles to millipedes. [Eisner, 1970])
Small invaginations develop in the epidermis between sclerites (plates of cuticle). By wiggling, the insect can squeeze more quinones onto its surface when they're needed.
The invaginations deepen. Muscles are moved around slightly, allowing them to help expel the quinones from some of them. (Many ants have glands similar to this near the end of their abdomen. [Holldobler & Wilson, 1990, pp. 233-237])
Some invaginations (now reservoirs) become so deep that the others are inconsequential by comparison. Those gradually revert to the original epidermis.
In various insects, different defensive chemicals besides quinones appear. (See Eisner, 1970, for a review.) This helps those insects defend against predators which have evolved resistance to quinones. One of the new defensive chemicals is hydroquinone.
Cells that secrete the hydroquinones develop in multiple layers over part of the reservoir, allowing more hydroquinones to be produced. Channels between cells allow hydroquinones from all layers to reach the reservoir.
The channels become a duct, specialized for transporting the chemicals. The secretory cells withdraw from the reservoir surface, ultimately becoming a separate organ.
This stage -- secretory glands connected by ducts to reservoirs -- exists in many beetles. The particular configuration of glands and reservoirs that bombardier beetles have is common to the other beetles in their suborder. [Forsyth, 1970]
Muscles adapt which close off the reservoir, thus preventing the chemicals from leaking out when they're not needed.
Hydrogen peroxide, which is a common by-product of cellular metabolism, becomes mixed with the hydroquinones. The two react slowly, so a mixture of quinones and hydroquinones gets used for defense.
Cells secreting a small amount of catalases and peroxidases appear along the output passage of the reservoir, outside the valve which closes it off from the outside. These ensure that more quinones appear in the defensive secretions. Catalases exist in almost all cells, and peroxidases are also common in plants, animals, and bacteria, so those chemicals needn't be developed from scratch but merely concentrated in one location.
More catalases and peroxidases are produced, so the discharge is warmer and is expelled faster by the oxygen generated by the reaction.
The walls of that part of the output passage become firmer, allowing them to better withstand the heat and pressure generated by the reaction.
Still more catalases and peroxidases are produced, and the walls toughen and shape into a reaction chamber. Gradually they become the mechanism of today's bombardier beetles.
The tip of the beetle's abdomen becomes somewhat elongated and more flexible, allowing the beetle to aim its discharge in various directions.
Why, that sounds like a series of random... oh, forget it. You'll probably ignore this too.
I particularly liked "Everything in evolution is supposed to make perfect sense and have a logical purpose" Says who? The whole freaking point of evolution is that it is a choatic process with an ordered outcome. I expect there were lots of little beetles blowing themselves up at some point. Guess what? Those beetles didn't produce any offspring, and thats why you don't see any. The ones that didn't blow themselves up produced offspring. Oh look, more beetles.
The fear of evolution is partly based on the idea that man is perfect, and then from that the fear that a perfect being could have evolved from chaos.
The flaw is believing that man is perfect.
Let me preface this by saying that I do believe in God (after thinking everything through and deciding for myself)
:) ). This was all because I felt a bond to my common man, not because I feared reprisal in the afterlife. How were my morals any less real than the morals of those who 'do right' because their God tells them to? Belief in God in no way equates or even implies morality or ethics. Look at the Sept. 11th hijackers. They most likely believed very strongly in God. You could argue that they didn't follow God's teachings, but the point is that they believed they were.
Just because evolution was taught as truth in high school and college, and it allows you to live your life any way that you want without concern for life after death or accountability to a higher power doesn't mean that you should buy it.
It upsets me that so many people who believe in God imply that simply because someone does not believe in God they cannot have any true morals or ethics. I did not believe in God through most of high school and college, yet (I believe) I was a very moral person. I did not drink, did not do drugs, worked hard, tried not to lie (though I was somewhat less successful in that regard
I realize that this is going to get modded down, but it frustrates me that so many people who pull this "I'm an intellectual therefore I believe in evolution not God" crap are actually simple drones of the left. Think for yourself, will ya?
(Note, I have moderator access, but I think responding is much better to this than modding down)
I am sure there are just as many drones on the right who simply believe in God because it is easier. Most Christians (the majority of religious people in America) have not read the Torah, Koran or Bhagavad Gita. Why is this? Is it because they know after reading the Bible that nothing else can possibly be correct? They may say that to themselves, but I doubt it is the truth. I find it much more likely that the Bible is what they were brought up with, and it is simply easier to follow what they already know as opposed to working to figure out what they can truly put their faith in.
I find it perplexing that many people take the time to diligently study the religion they were brought up to know, yet few take even scant moments to study the countless other religions in this world. Well, no, it doesn't really perplex me. It saddens me.
--David