Monday, September 28, 2009
I have dealt with the Cambrian Explosion at length before. Here I'll add just one new point, illustrated by the flatworms, Platyhelminthes. This great phylum of worms includes the parasitic flukes and tapeworms, which are of great medical importance. My favorites, however, are the free-living turbellarian worms, of which there are more than 4,000 species: that's about as numerous as all the mammal species put together. They are common, both in water and on land, and presumably have been common for a very long time. You'd expect, therefore, to see a rich fossil history. Unfortunately, there is almost nothing. Apart from a handful of ambiguous trace fossils, not a single fossil flatworm has ever been found. The Platyhelminthes, to a worm, are "already in an advanced state of evolution, the very first time they appear. It is as though they were just planted there, without any evolutionary history." But in this case, "the very first time they appear" is not the Cambrian but today. Do you see what this means, or at least ought to mean for creationists? Creationists believe that flatworms were created in the same week as all other creatures. They have therefore had exactly the same time in which to fossilize as all other animals. During all the centuries when all those bony or shelly animals were depositing their fossils by the millions, the flatworms must have been living happily alongside them, but without leaving the slightest trace of their presence in the rocks. What, then, is so special about gaps in the record of those animals that do fossilize, given that the past history of the flatworms is one big gap: even though the flatworms, by the creationists' own account, have been living for the same length of time? If the gap before the Cambrian Explosion is used as evidence that most animals suddenly sprang into existence in the Cambrian, exactly the same "logic" should be used to prove that the flatworms sprang into existence yesterday. Yet this contradicts the creationist's belief that flatworms were created during the same creative week as everything else. You cannot have it both ways. This argument, at a stroke, completely and finally destroys the creationist case that the Precambrian gap in the fossil record can be taken as evidence against evolution.
I've done a little research on this, and seems that there might actually be one flatworm fossil, which you can read about here. However, an article in American Scientist states that "no fossil flatworms are definitely identified in the fossil record" so perhaps that finding is controversial, or perhaps it is the lonely (or near lonely) representation of flatworms in the fossil record. Either way Dawkins' point still stands.
Sunday, September 27, 2009
Saturday, September 26, 2009
After Kirk Cameron used the non-existence of the ‘crocoduck’ (half crocodile, half duck) as an argument against evolution, crocoduck-mania took to the web like wildfire. But instead of becoming the silver-bullet argument Kirk Cameron had hoped for, it became the icon of evolution-denying stupidity at which we can all laugh.
To celebrate this epic failure by the anti-evolution crowd, RichardDawkins.net has created the “University of Intelligent Design Crocoducks” team t-shirt!
The design features ‘Chuck the Crocoduck,’ the official mascot of the University of Intelligent Design, founded in 4004 BC (not to be confused with the very real Liberty University).
Enjoy demolishing the brain-dead Intelligent Design/Creationist “arguments” (we use the term generously) for friends, family or strangers, with Chuck the Crocoduck’s help!
Someone posted a very weird old video of the chef Julia Child explaining abiogenesis.
A new peer reviewed paper was published that shows that (astonishingly) all proteins used by life are related to one another through no more than 7 intermediate proteins. A less technical write-up can be found here.
Ray Comfort went on the 700 club and repeated the same bullshit arguments against evolution that PZ Myers corrected him on months ago.
Thursday, September 24, 2009
If you miss the show, go to the site about 10EST/9CEN and the show should be up for you to listen to free. And if you like it, subscribe. Reggie (the Infidel Guy) could use all the help he can get these days!
My first impression of it is that it is excellent. First, aesthetically: The cover of the book is beautiful, and there are numerous color photo inserts throughout the book that illustrate embryological development, fossils, and so on.
Dawkins takes a couple of chapters expounding upon transitional fossils, one on plant and animal transitionals, and another on human transitionals. He has really taken pains to correct common misconceptions about evolution, and he often corrects the same misconception multiple times so as to make sure that the reader fully understands why monkeys still exist, for instance.
He also does an excellent job of rebutting the old 'common design' claim people make in response to evolution. Remarkably, his answer to this is nearly identical to mine.
From now on, creationists are without excuse for being ignorant about Evolution. Every time a creationist comes to my blog to challenge me, I'm going to send them to this post, which will give them directions for becoming educated about evolution. If they won't listen to the efforts of world famous biologists to educate them, then I cannot expect that they will listen to my efforts to educate them on evolution or that they will be receptive to them. So, if you are a creationist, or someone genuinely curious about evolution, here is what I recommend for you:
1. Read The Greatest Show on Earth: The Evidence for Evolution
2. Check out an Index to Creationist Claims, which thoroughly rebuts just about every creationist argument there is. Search Talk.Origins to find the answers you need to the questions you have.
3. Read Why Evolution Is True
It's a little more in-depth, provides even more evidence for Evolution than Dawkins, and assumes the reader has at least a little knowledge of evolution.
4. Read the 29 Evidences for MacroEvolution. This is much shorter than any book you'll read, but it is fairly in depth and it lays out just about all the evidence (or all the main lines of evidence) for evolution that exists.
Wednesday, September 23, 2009
Monday, September 21, 2009
I get tired of correcting Christians on "survival of the fittest" when they ought to damn well know better. "Survival of the Fittest" is always shouted as if it meant brutal, gory, deadly fighting in which only a few brutes make it through. That is not what it natural selection is. Natural selection is simply the fact that certain alleles/genes become more common in a population because those alleles or genes allow for a higher chance of survival or a longer lifespan to those who have them. Like how antibiotic resistant bacteria become prominant in first world countries where antibiotics are frequently used, but antibiotic bacteria are rare in countries where antibiotics are not available or are not used as much.
Saturday, September 19, 2009
Friday, September 18, 2009
Wednesday, September 16, 2009
Sunday, September 13, 2009
The bottom line is that our actions are determined by our desires and our knowledge of how to fulfill those desires (as well as our intelligence to calculate from our knowledge the best way to fulfill a desire). Nothing else makes sense. I mean, if we have immaterial souls, how do our souls decide what we do? Does a soul choose to do something based on its priorities? If so, then that's the same thing as compatibilist free will, only instead of a soul, I believe our brain chooses based on what it desires most. If not, then what determines our choices? If nothing determines our choices, then by definition our actions are random and we cannot be held accountable for what we do.
What does this have to do with God? Well, a perfect, all knowing and all powerful God could create people who have completely good desires, thereby eliminating evil caused by the abuse of free will.
Before I finish this post I must address one further point: The charge that compatibilist free will would lead to moral anarchy. The argument is one which you may have already thought of: If we cannot control what desires we have, then how can we hold a criminal responsible. After all, given the same desires, knowledge, intelligence, and situation he would inevitably commit the crime he committed. This is true. But we still must hold him accountable because we want to provide a deterrant for other criminals contemplating doing the same act.
Saturday, September 12, 2009
It seems to me, as an interested layman (I have a B.S. but it's in computer science), that the most interesting hypothesis of intelligent design is: "Things that have a common designer will also have a common design." This is interesting to me because we should actually be able to make predictions about actual things in nature based on it, and test them against what we find. I've read it many times in ID and creationist discussions, so I don't think it should be controversial. What I want to do is set up a few scenarios where it should be able to make predictions, and see what predictions it will actually make.
So let's start with something pretty much everybody does: breathing. You inhale, you exhale. Lungs, it turns out, are a pretty remarkable medium of transmitting oxygen from the air around us to the bloodstream. And lungs are shared by pretty much all terrestrial vertebrates that I'm aware of. We also know that fish, for the most part, don't have lungs. They have gills, which are efficient machines for extracting oxygen from the water. Myriad kinds of fish and aquatic animals have gills to breathe underwater. So a design hypothesis would be: terrestrial vertebrates have commonly designed lungs, and aquatic vertebrates have commonly designed gills.
But then...you've got troublemakers. Like the whales and dolphins. These are animals that are strictly aquatic - they have no ability to go about and feed themselves on land. Yet they have lungs, just like the terrestrial mammals. This is such a wacky design for an aquatic creature that whales actually have to think about when to breathe, unlike you or I. Or fish, for that matter. Whales are magnificent creatures, and great predators in many cases, but we're talking about common design - unless it's stretched so far as to be meaningless, it makes no sense to me to say that common design should include using the land design out in the ocean. From a standpoint of "common design" it would be like creating a submarine with an engine designed like a car's, where it periodically has to surface, uncover the exhaust manifold and let some air in. This is unacceptable from a design standpoint - yet, if submarines were animals that had evolved by natural selection from cars, we might expect to see it if an air-based cooling system was powerfully encoded in their genetics.
There is much convergent evolution between the poster's thoughts and mine. I've noticed that bat and bird wings have adapted the same five digit hands in different ways to create a wing. How could common design explain that? Michael Shermer noticed long ago that fish swim by moving their tails from side to side, while whales and dolphins swim by moving their tails up and down, as land mammals do. How does common design explain this? It can't, unless the concept of "common design" is stretched so far as to be meaningless, as the poster said.
Friday, September 11, 2009
Thursday, September 10, 2009
Tuesday, September 8, 2009
Monday, September 7, 2009
"Mammals without enamel are descended from ancestral forms that had teeth with enamel," Springer said. "We predicted that enamel-specific genes such as enamelin would show evidence in living organisms of molecular decay because these genes are vestigial and no longer necessary for survival."
Now his lab has found evidence of such molecular "cavities" in the genomes of living organisms. Using modern gene sequencing technology, Meredith discovered mutations in the enamelin gene that disrupt how the enamelin protein is coded, resulting in obliteration of the genetic blueprint for the enamelin protein.
Results of the study appear in the Sept. 4 issue of the open-access journal PLoS Genetics.
Darwin argued that all organisms are descended from one or a few organisms and that natural selection drives evolutionary change. The fossil record demonstrates that the first mammals had teeth with enamel. Mammals without enamel therefore must have descended from mammals with enamel-covered teeth.
"We could therefore predict that nonfunctional vestiges of the genes that code for enamel should be found in mammals that lack enamel," Springer said. "When we made our predictions, however, we did not have sequences for the enamelin gene in toothless and enamelless mammals. Since then my lab worked on obtaining these sequences so we could test our prediction."
Previous studies in evolutionary biology have provided only limited evidence linking morphological degeneration in the fossil record to molecular decay in the genome. The study led by Springer takes advantage of the hardness of enamel and teeth to provide more robust evidence for the linkage.
"The molecular counterpart to vestigial organs is pseudogenes that are descended from formerly functional genes," Springer explained. "In our research we clearly see the parallel evolution of enamel loss in the fossil record and the molecular decay of the enamelin gene into a pseudogene in representatives of four different orders of mammals that have lost enamel."
Broadly, the research involved the following steps: First, Meredith collected the DNA sequences for the enamelin gene in different mammals. Next, the researchers analyzed sequences using a variety of molecular evolutionary methods, including new approaches developed by Springer's group. Finally, the group used the results of their analyses to test previous hypotheses and generate new ones.
Saturday, September 5, 2009
Thursday, September 3, 2009
Wednesday, September 2, 2009
From Secularism.org.uk :
The Pope has claimed that atheism is responsible for the destruction of the environment. In a speech at the Vatican on Wednesday, Ratzinger said: “Is it not true that inconsiderate use of creation begins where God is marginalized or also where his existence is denied? If the human creature's relationship with the Creator weakens, matter is reduced to egoistic possession, man becomes the ‘final authority,’ and the objective of existence is reduced to a feverish race to possess the most possible.”
Terry Sanderson, President of the National Secular Society, commented: “This is rich coming from the leader of an organisation that has plundered the world to enrich itself. As he sits in his golden palaces, surrounded by unimaginable luxury and material wealth, he lectures the rest of us about restraint and greed. We have nothing to learn about environmentalism from this hypocrite.”