Polemics

How brief was the period in which the Cambrian phyla suddenly appeared?

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The Cambrian explosion refers to the sudden appearance of new body plans in the fossil record. ID proponents think that the period is between 5-10 million years at the most. Naturalists want to stretch out the period in which the body plans appear to tens of millions of years. The two sides can’t both be right. What’s the truth?

Evolution News has the answer.

Excerpt:

To establish the length of the most explosive period of innovation within the Cambrian explosion itself, Meyer cites the work of MIT geochronologist Samuel Bowring and his colleagues as well the work of another group led by Smithsonian paleontologist Douglas Erwin. The Bowring-led study showed that (in their words) “the main period of exponential diversification” within the Cambrian lasted “only 5-6 million years” (emphasis added). Meyer explains:

An analysis by MIT geochronologist Samuel Bowring has shown that the main pulse of Cambrian morphological innovation occurred in a sedimentary sequence spanning no more than 6 million years. Yet during this time representatives of at least sixteen completely novel phyla and about thirty classes first appeared in the rock record. In a more recent paper using a slightly different dating scheme, Douglas Erwin and colleagues similarly show that thirteen new phyla appear in a roughly 6-million-year window. (p. 73)

[…][T]ake a look first at the following figure that Bowring and his colleagues included in their definitive 1993 article, published in the journal Science. They use radiometric methods to date the different stages of the Cambrian period, including the crucial Tommotian and Atdabanian stages in which the greatest number of new animal phyla and classes arise. Note that the so-called Manykaian stage of the Cambrian period lasts about 10-14 million years. Note also that the main pulse of morphological innovation didn’t begin during this stage but rather during the Tommotian and Atdabanian — a period that they describe as taking between “5 to 10 million years,” and in a more detailed passage as taking about 5-6 million years.

[…]In the figure above, the Tommotian and Atdabanian stages of the Cambrian period together span only about 5 million years, starting at about 530 and ending about 525 million years ago. Bowring’s figure also depicts the total number of classes and orders present at any given time during the Cambrian period. The biggest increases in morphological innovation occur during the Tommotian and Atdabanian stages. Indeed, during this period the number of known orders nearly quadruples. Moreover, Bowring and his colleagues also make clear that this period corresponds to the main pulse of Cambrian morphological innovation as measured by the number of new phyla and classes that first appear. They note that, while a few groups of animals do arise in the earliest Manykaian stage of the Cambrian, the most rapid period of “exponential increase of diversification,” corresponding to the Tommotian and Atdabanian stages, “lasted only 5 to 6 m.y.”

You can see the figure they are reference in the Evolution News article.

Also, check out these clips that explain the Cambrian explosion:

Part 1:

Part 2:

The first clip features James Valentine, a professor of biology at the University of California who just co-authored a new book on the Cambrian explosion and is not a proponent of intelligent design.

The consensus among scientists regarding the period of time in which the new body plans appear is 5-6 million years. Biologically speaking, that’s a blink of an eye. You aren’t going that kind of complexity and innovation in such a short period of time any more than you can expect to win the lottery by buying 5-6 million tickets when the odds of winning are 1 in a googol (10 to the 100th power – 1, followed by 100 zeroes). You don’t have enough lottery tickets to make winning the lottery likely. Similarly, 5-6 million years is not enough time for naturalistic mechanisms to code brand new body plans from scratch. It would be like trying to research and write a Ph.D thesis during a single lunch hour. It’s just not enough time to produce the amount of information that’s required.

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Commentary

Greg Koukl: six things you have to believe to be a Christian

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Here is the article on the Stand to Reason web site describing essential Christian beliefs.

Excerpt:

The six essential doctrines would be: the Trinity, the deity and humanity of Christ, the bodily resurrection, man’s fallenness and guilt, salvation by grace through faith by the substitutionary atonement of Jesus Christ, and belief that Jesus is the Messiah. And you have a seventh doctrine that strikes me as a functional necessity, that is the ultimate authority of Scripture without which none of the other truths can be affirmed or asserted with confidence.

By the way, it’s really important that people know these doctrines because many Christians are quite kind-hearted and they end up not being very careful about drawing distinctions between truth and falsity because they don’t want to disagree. I understand that. But if you were really kind-hearted then you would be honest and straight-forward with people about the demands of the gospel on their lives. The demand of the gospel is that you believe particular things to be true. It’s not just a matter of mere belief, as if these are just some incidental details of theology that you might happen to be mistaken about. And if you just happen to be mistaken, why should you go to hell because of that?

You don’t go to hell because you just happen to mistake a doctrine. You go to hell because you have broken God’s law. It is very critical to understand that. God only judges guilty people. People get judged by God not because they mess up on their theology but because they are guilty. People who are guilty get condemned. That’s it. There is a way to get around that but you’ve to know a couple of particular things that are true before you can take advantage of the forgiveness God offers. That’s where the essential doctrines come in.

I think it’s a good thing to go back and refresh ourselves on the basics of the gospel once in a while, and this article does a pretty good job of doing that in a basic, understandable way. I’m posting this for some of the non-Christians I know who ask me questions like this rather than apologetics questions. Sometimes people just want to ask what I believe, and not how I know what I believe. Well, this is what I believe.

News

Panama seizes shipment of missile guidance equipment from Cuba bound for North Korea

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RSN-75 Radar for SA-2 SAM
RSN-75 Radar for SA-2 SAM

From Investors Business Daily.

Excerpt:

Cuba, long derided in international policy circles as a basket case and no threat to the U.S., has been caught smuggling weapons of war to North Korea in blatant violation of U.N. sanctions. This is a wake-up call.

Sharp-eyed Panamanian authorities, watching the North Korean freighter Chong Chon Gang since June, received intelligence it might be shipping illegal drugs, something it had been caught doing before.

As the vessel lumbered into the Atlantic side of the Panama Canal from Cuba, Panamanian authorities cornered the 450-foot rust-bucket, battled a maniacally violent crew who slashed ship lines to make it hard to unload the ship, and then watched as the ship’s captain tried to kill himself before having a heart attack.

After subduing the crew, the Panamanians found no drugs buried beneath sloppily packed brown sugar, but did find defensive RSN-75 “Fan Song” fire-control radar equipment for SA-2 surface-to-air missiles.

The discovery, and the crew’s behavior, were signs of something big the North Koreans didn’t want known — weapons smuggling, a violation of both United Nations sanctions prohibiting all sales of weapons to North Korea and Panama’s own laws governing the canal.

“You cannot go around shipping undeclared weapons of war through the Panama Canal,” declared Panamanian President Ricardo Martinelli, a U.S. ally, who tweeted a photo of the illegal shipment for the world to see.

It’s significant that the enabler of this violation of international law was none other than Cuba, which has worked hard to convince the Obama administration to drop all travel and trade sanctions against it — and which is currently negotiating a migration pact with the U.S. It’s time to stop that right now, and sanction Cuba further.

The brazen shipment of Russian-made weapons through Panama signaled that little has changed in Cuba — a state sponsor of global terror that has in fact been trying to destroy the U.S. since 1962.

“This is a serious and alarming incident that reminds us that the North Korean regime continues to pursue its nuclear and ballistic programs, and will stop at nothing in that pursuit,” said House Foreign Affairs Subcommittee Chairwoman Ileana Ros-Lehtinen. “It also illustrates that the Castro tyranny continues to aid and abet America’s enemies and continues to pose a national security threat to the United States so long as the Castro apparatchik holds control over the island.”

It’s also the work of a rogue state. And at just 90 miles away, one that is as chillingly close to our shores as it is warm and friendly to North Korea.

[…]Although it’s unknown why North Korea, a major weapons exporter, is importing weapons from Cuba right now, defense analysts speculate that the weapons may be making their way back to Pyongyang for an upgrade and return to Cuba.

That would be worrisome given that North Korea has said it means to strike the U.S. on its own home turf. What better launching pad could it ask for than Cuba?

Two weeks ago, North Korea’s military commander visited Cuba to a red-carpet welcome. The visit raises questions as to what the two discussed — and, given the threat we see now, whether U.S. intelligence was aware of it.

If there is one thing that the United States definitely should not do, it’s dropping sanctions against Cuba.