Why evolution is true

by Caedes 7 Replies latest social current

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  Caedes

  Coyne’s chapter on “The Engine of Evolution” begins with a splendidly macabre example. Giant Japanese hornets raid the nests of honeybees to feed their larvae. A single hornet scout discovers a beehive and marks it “for doom” with a sort of chemical black spot.

  "Alerted by the mark, the scout’s nestmates descend on the spot, a group of twenty or thirty hornets arrayed against a colony of up to 30,000 honeybees. But it’s no contest. Wading into the hive with jaws slashing, the hornets decapitate the bees one by one. With each hornet making heads roll at a rate of forty per minute, the battle is over in a few hours: every bee is dead, and body parts litter the hive. Then the hornets stock their larder."

  Coyne’s purpose in telling the story is to contrast the terrible fate of European bees, introduced into Japan, with native Japanese bees that have had time to evolve a defence.

  "And their defense is stunning – another marvel of adaptive behavior. When the hornet scout first arrives at the hive, the honeybees near the entrance rush into the hive, calling nestmates to arms while luring the hornet inside. In the meantime, hundreds of worker bees assemble inside the entrance. Once the hornet is inside, it is mobbed and covered by a tight ball of bees. Vibrating their abdomens, the bees quickly raise the temperature inside the ball to about 117 degrees Fahrenheit. In twenty minutes the hornet scout is cooked to death, and – usually – the nest is saved."

  Coyne adds that the bees can survive the high temperature, but it is another insight of the “gene’s eye view” that this would not be necessary in order for natural selection to favour the adaptation. Worker bees are sterile: their genes survive, not in the workers themselves but as copies in the bodies of the minority of hive members destined for reproduction. If the workers in the centre of the ball were cooked alongside the hornet, it would be well worth the sacrifice. Copies of their genes “for cooking” live on.

  Quoted from a very interesting review of "why evolution is true" by Jerry Coyne (Review by Richard Dawkins in the TLS)

  http://entertainment.timesonline.co.uk/tol/arts_and_entertainment/the_tls/article5707143.ece
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  Caedes

  Coyne is right to identify the most widespread misunderstanding about Darwinism as the idea that, in evolution, “everything happens by chance”. This common claim is flat wrong – obviously wrong, transparently wrong, even to the meanest intelligence (a phrase that has me actively restraining myself). If evolution worked by chance, it obviously couldn’t work at all. Unfortunately, instead of working out that they have probably misunderstood evolution, creationists conclude, instead, that evolution must be false. This one misunderstanding, single-handed, accounts for much of the uncomprehending opposition to evolution that made it necessary for Jerry Coyne to write his book in the first place. The need was great; the execution is superb. Please read it.

  Another interesting quote from the same review.
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  Black Sheep

  The Vatican has admitted that Charles Darwin was on the right track when he claimed that Man descended from apes.

  A leading official declared yesterday that Darwin’s theory of evolution was compatible with Christian faith, and could even be traced to St Augustine and St Thomas Aquinas. “In fact, what we mean by evolution is the world as created by God,” said Archbishop Gianfranco Ravasi, head of the Pontifical Council for Culture. The Vatican also dealt the final blow to speculation that Pope Benedict XVI might be prepared to endorse the theory of Intelligent Design, whose advocates credit a “higher power” for the complexities of life.

  So there you have it. From the Vatican itself. http://www.timesonline.co.uk/tol/comment/faith/article5705331.ece

  We can stop all the bickering and go and have a nice hot cup of tea....or a beer.... and get on with more important things.

  Cheers

  Chris
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  Caedes

  As soon as the creationists stop trying to inflict atrology as an alternative to astronomy or creationism as an alternative to evolution within our schools then I will get on with more important things!

  Magical thinking is a dangerous crime when inflicted on on any area of public policy and until such time until it has lost it's baleful influence I shall continue 'bickering'.
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  cameo-d

  In order for a mutation to be inherited, it must occur in the genetic material of a sex cell . Estimates of the frequency of mutations in human sex cells generally are about 1 per 1 0,000-1 ,000 ,000 for any specific gene. Since humans have approximately 20,000-25 ,000 genes, it is to be expected that most sex cells contain at least one gene mutation of some sort. In other words, mutations are probably common occurrences even in healthy people. Most probably do not confer a significant advantage or disadvantage because they are point mutations that occur in non-gene coding regions of DNA molecules. They are relatively neutral in their effect. However, some mutations are extremely serious and can result in death before birth, when an individual is still in the embryonic or early fetal stages of development.

  Mutations can occur naturally as a result of occasional errors in DNA replication. They also can be caused by exposure to radiation, alcohol, lead, lithium, organic mercury, and some other chemicals. Viruses and other microorganisms may also be responsible for them. Even some commonly prescribed drugs are thought to be teratogens

  ...

  M utations appear to be spontaneous in most instances. That does not mean that they occur without cause but, rather, that the specific cause is almost always unknown. Subsequently, it is usually very difficult for lawyers to prove in a court of law that a mutagen is responsible for causing a specific mutation in people. With the aid of expert scientific testimony, they can often demonstrate that the mutagen can cause a particular kind of mutation. However, that is not the same thing as proving that a plaintiff's mutation was caused by that mutagen instead of some others.

  The great diversity of life forms that have been identified in the fossil record is evidence that there has been an accumulation of mutations producing a more or less constant supply of both small and large variations upon which natural selection has operated for billions of years. Mutation has been the essential prerequisite for the evolution of life.

  In order for a mutation to be subject to natural selection, it must be expressed in the phenotype of an individual. Selection favors mutations that result in adaptive phenotypes and eliminates nonadaptive ones. Even when mutations produce recessive alleles that are seldom expressed in phenotypes, they become part of a vast reservoir of hidden variability that can show up in future generations. Such potentially harmful recessive alleles add to the genetic load of a population.

  excerpted from Synthetic Theory of Evolution: Mutation

  http://anthro.palomar.edu/synthetic/synth_3.htm
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  Seeker4

  One of my absolute favorite websites is Edge, www.edge.org/documents/archive/edge274.html, and it is by far one of the most intellectually stimulating sites I've found, second only to JWD/N of course.

  Jerry Coyne contributes a lot to the site, and the discussions there of science and politics are fantastic. We need more scientists speaking up like Coyne does.

  S4
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  BurnTheShips

  I get the Edge newsletter. Awesome stuff.
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  ninja

  If I hear about a gang of neds who are in the area ....luring householders out of their house,battering them and stealing their goods

  then ninja (always evolving) arms himself with a baseball bat.........ninja moves from man to superman......ninjzsche

  only kidding.....not wanting to stir up a hornets' nest....he he