Today’s New Reason To Believe

Posted by Fazale ‘Fuz’ Rana, Ph.D.

Punctuated equilibrium doesn’t have a viable mechanism

This past Thanksgiving, my family and I (along with some good friends) rode down to the bottom of the Grand Canyon on mules. That night we ate dinner at the Phantom Ranch and the next day rode back out of the canyon. It was an amazing experience to be immersed in God’s creation—but also terrifying at times to be on the back of a mule maneuvering on rugged and narrow trails overlooking sheer drops of hundreds of feet. I was sure thankful my mule (Tin Man) had a good sense of equilibrium. If he didn’t, it would have been all over for both of us on a few occasions.

The evolutionary paradigm also depends on equilibrium (of sorts). Many paleontologists assert that biological evolution occurs by a non-Darwinian mechanism referred to as punctuated equilibrium. According to this view, biological evolution occurs rapidly—in spurts—followed by long periods of stasis.

Proponents of punctuated equilibrium posit that evolution only occurs when a small subpopulation of a species becomes isolated from the general population. If the isolated subpopulation becomes confined to the periphery of the species’ normal geophysical range, evolution will occur rapidly, say evolutionists, if the environmental and predatory pressures found in the periphery differ significantly from those found in the species’ typical geographical range. Experiencing different conditions, the peripheral subpopulation is not ideally suited for its environment. This mismatch provides the driving force for evolutionary change. When occupying its normal range, natural selection prevents a species well-suited for its environment from evolving. In other words, natural selection promotes stasis.

Punctuated equilibrium seems to explain the fossil record. If a new species emerges rapidly from a small peripheral subpopulation, it will seem as if that new species appears suddenly in the fossil record, and few if any transitional intermediates would be expected.

Even though punctuated equilibrium can explain the troubling features of the fossil record, one key question remains. Does the mechanism undergirding punctuated equilibrium actually work? Research results published in 2001 indicated, no.

Theoretical work by University of Oregon scientists shows that the essential processes making up punctuated equilibrium’s mechanism lead to extinction, not evolution. These scientists demonstrated that risk of extinction significantly increases for a species when its population becomes disconnected. Moreover, environmental changes and habitat fragmentation exacerbate a disconnected population’s susceptibility to extinction. Population and habitat fragmentation, along with an altered environment, stand at the center of punctuated equilibrium’s mechanism.

Investigators from Washington University in St. Louis produced field work confirming the work done by the scientists from the University of Oregon. Studying collared lizards in the Missouri Ozarks, the Washington University scientists showed that habitat fragmentation doesn’t drive speciation; rather it leads to extinction.

These two studies create a serious problem for the evolutionary paradigm. As discussed last week, strict Darwinian evolution lacks the necessary corroboration from the fossil record and cannot be declared a fact. Punctuated equilibrium “explains” the fossil record, yet fails due to the absence of a legitimate mechanism and must be rejected as an explanation for life’s history.

Though many evolutionary biologists would claim that I am off-balance, it seems to me that the absence of any conceivable naturalistic explanation for the origin and natural history of life’s major groups opens the possibility for the work of a Creator.

by Jeff Zweerink

Disaster movies seem to be a staple for Hollywood. One such disaster movie that I found enjoyable (enough to watch it four times on my way to Japan) was The Core. The movie opens by showing some (unrealistic) consequences of Earth’s magnetic field disappearing (caused by a stoppage of the rotation of Earth’s core). The remainder of the movie details how a team of scientists attempt to restart Earth’s core and save the planet. While the film abounds with scientific inaccuracies and impossibilities, its premise highlights an important characteristic of Earth’s habitability, namely a strong magnetic field.

Venus and Earth are remarkably similar in composition and size. Venus has 81% of Earth’s mass, and its radius and density are only about 5% smaller than Earth’s. Due to their forming in a similar section of the solar system, both Earth and Venus likely started covered with water and had essentially identical atmospheres. While these two “sister planets” began similarly, they could not be more different today in terms of their habitability.

Earth’s atmosphere consists of mainly nitrogen (78%) and oxygen (21%), with trace amounts of other gases like carbon dioxide and helium. Additionally, abundant clouds of water vapor fill the skies. In stark contrast, Venus’ atmosphere is comprised of mostly carbon dioxide (96%) and nitrogen (3%) with dense clouds of sulfuric acid! Earth’s atmosphere causes surface temperatures around 70^oF, Venus’ surface sits around 800^oF. What caused this difference?

Many factors contribute to the disparity between Earth and Venus, but recent results from the Venus Express satellite highlight one of the more important differences. Because Earth rotates once every 24 hours, this motion causes its iron core to generate a strong magnetic field. This magnetic field shields Earth from cosmic rays, in addition to protecting Earth’s atmosphere from the solar wind. Venus rotates only once for every 243 Earth days. Consequently, Venus has no significant magnetic field to shield its atmosphere from the solar wind.

Without a magnetic shield, the solar wind strips away all the water from Venus’ surface. Ultraviolet radiation from the Sun breaks water molecules down into two hydrogen ions and one oxygen ion (atoms with an electric charge due to an extra electron or a deficiency of an electron). The charged particles in the solar wind accelerate these ions and strip them from the atmosphere. However, Earth’s magnetic field deflects the solar wind around the atmosphere so the ions are not stripped off into space. The results published in Nature from the Venus Express mission demonstrate that the ions coming from Venus match the composition expected if water is being stripped from its atmosphere. The water currently being stripped from Venus arises from recent small comet impacts that deposit water in Venus’ atmosphere (similar processes occur on Earth also). However, the solar wind has also stripped away all the water that Venus started with over four billion years ago.

These findings highlight how a habitable planet must not only be similar in size and composition to Earth, but it also must have a strong magnetic field. Thus, one must read optimistic announcements such as this with a bit of caution.

Kenneth Richard Samples

The doctrine of the Incarnation (God in the flesh) stands at the very heart of historic Christianity. This biblically derived doctrine teaches that the eternal Word, the second person of the Trinity, took unto himself a human nature and became man without in any way diminishing his deity (John 1:1, 14, 18; Philippians 2:5-6; Colossians 2:9; 1 John 4:1-3). Christian orthodoxy therefore views Jesus Christ as a single person who nevertheless possesses both a divine and human nature. Those two natures (divine and human) find their union in the person of Christ (hypostatic union). This theological understanding of the Incarnation led the ancient Christians to refer to Jesus as the theanthropos (Greek: the “God-man”).

Some people today, however, think that the idea of Jesus possessing both a divine and a human nature is logically contradictory. The specific charge is that Jesus’ human qualities and characteristics (the limits and boundaries of his human nature) cannot be connected with his divine qualities and characteristics (the unlimited and boundless character of his divine nature). This challenge can potentially stand as an obstacle to a person who is genuinely considering the truth-claims of historic Christianity.

In this brief article, I will offer a way to think about the union of Christ’s two natures that may avoid this logical entanglement. Remember, however, that I am posing this idea as merely a hypothetical way to resolve this challenge. I am not suggesting that this is the only or even the best way to respond to the issue. I am engaging in what I hope is a helpful form of speculative philosophical theology. The recommended reading at the end of the article offers other suggested philosophical-theological approaches.

The Union of the Two Natures of Christ

Couldn’t Jesus have what amounts to a “special” human nature? That is, maybe Jesus’ human nature is both like and unlike the common, generic nature that the rest of humanity possesses. After all, while Jesus was fully human (like every other human being) he was not solely human (unlike every other human being). In other words, maybe Jesus’ human nature was distinct from the typical nature that every other human being possesses. In this way, Jesus holds a fully human nature that is still compatible with a person who is not solely human (also possessing a divine nature). The idea is to rethink the exact nature of Christ’s humanity without diminishing it.

If Jesus possesses a special human nature (call it “fully human plus”), then maybe he could suffer real limitations in time, space, and knowledge, yet the limited human nature would not conflict with his simultaneous possession of an unlimited divine nature. Accordingly, one could argue that the way in which Jesus was limited (special human nature) is in a different respect from the way in which he was unlimited (divine nature).

The law of noncontradiction asserts that two contradictory propositions cannot both be true at the same time and in the same respect. Formulated as I have stated it, the Incarnation (a fully human but not solely human nature that is uniquely compatible with a divine nature) wouldn’t necessarily violate the law of noncontradiction.

Of course, the doctrine of the Incarnation involves much divine mystery and my “fully human plus” theory also relies upon the miraculous creative power of God. Obviously, my brief venture into speculative philosophical theology definitely needs to be tested by Scripture, orthodox theological standards (creeds), and reason (1 Thessalonians 5:21).

For more on the Christian doctrine of the Incarnation, see chapter nine of my book, Without a Doubt: Answering the 20 Toughest Faith Questions. For another thoughtful approach to the issue of Christ’s two natures, see Thomas V. Morris, The Logic of God Incarnate.