Many independent measurements have established that the Earth and the universe are billions of years old. Geologists have found annual layers in glaciers that can be counted back 740,000 years. Using the known rate of change in radio-active elements (radiometric dating), some Earth rocks have been shown to be billions of years old, while the oldest solar system rocks are dated at 4.6 billion years. Astronomers use the distance to galaxies and the speed of light to calculate that the light has been traveling for billions of years. The expansion of the universe gives an age for the universe as a whole: 13.7 billion years old. (Updated April 16, 2012)

A complex biological structure with many interacting parts might appear, at first glance, as if it were originally created in its present form with all its interlocking components fully formed and intact. It doesn’t seem possible that they developed step by step via biological evolution. In Darwin’s Black Box, Michael Behe introduces a term that he and other proponents of Intelligent Design use for this concept: irreducible complexity.

Genesis 6-9 tells the fascinating story of Noah, the Ark, and the Flood. Some Christians interpret the text to mean that the biblical flood must have covered the entire globe. They also work to explain the evidence in rocks and fossils in terms of this world-wide flood. Other Christians do not feel the text requires that the flood be global, but could have covered the small region of earth known to Noah. The scientific and historical evidence does not support a global flood, but is consistent with a catastrophic regional flood. Beyond its place in history, the Genesis flood teaches us about human depravity, faith, obedience, divine judgment, grace and mercy.

Scientists have found multiple lines of evidence for evolution, not just one or two. These types of evidence are independent of each other, coming from sources as different as ancient fossils and modern genetics labs. Evidence also comes from comparing the anatomy of creatures living today. All creatures with four limbs (whether mammals, birds, or reptiles) have the same bone structure in each limb, pointing to their descent from a common ancestor. More evidence comes from biogeography. Isolated islands are missing common species found on the mainland, but are filled with many unique species that can be related by a common ancestor. Finally, evidence comes from embryonic development. As an embryo of a mammal grows, its heart develops through stages similar to fish, amphibians, and reptiles. God’s creation declares the history of life in many different ways. All these ways are pointing to a consistent picture of God creating through evolution.

In recent decades, scientists have discovered more about the beginnings of humanity. The fossil record shows a gradual transition over 5 million years ago from chimpanzee-size creatures to hominids with larger brains who walked on two legs. Later hominids used fire and stone tools and had brains as large as modern humans. Fossils of homo sapiens in east Africa date back nearly 200,000 years. Humans developed hearths for fire, stone points for spears and arrows, and cave paintings by 30,000 years ago. By 10,000 years ago, humans had spread throughout the globe. Genetic studies support the same picture. Humans share more DNA with chimpanzees than with any other animal, suggesting that humans and chimps share a relatively recent common ancestor. Also, the same defective genes appear in both humans and chimps, at the same locations in the genome—an observation difficult to explain except by common ancestry. Genetics also tells us that the human population today descended from more than two people. Evolution happens not to individuals but to populations, and the amount of genetic diversity in the gene pool today suggests that the human population was never smaller than several thousand individuals. Yet all humans, of all races, are descended from this group. Humanity is one family.

Darwin developed his theory of evolution by looking at scientific evidence available in the mid-1800s. Since then, the whole field of genetics has developed, adding a powerful independent line of evidence in support of evolution. Genes show how the physical traits of living things are handed down and modified from one generation to the next. By comparing the DNA of many organisms, scientists can map the relationships between species. This map is in remarkable agreement with Darwin’s predictions. The structure of chromosomes and particular genetic sequences point to the conclusion not just of common design, but common descent as well.

The “Cambrian Explosion” refers to the appearance in the fossil record of most major animal body plans about 543 million years ago. The new fossils appear in an interval of 20 million years or less. On evolutionary time scales, 20 million years is a rapid burst that appears to be inconsistent with the gradual pace of evolutionary change. However, rapid changes like this appear at other times in the fossil record, often following times of major extinction. The Cambrian Explosion does present a number of interesting and important research questions. It does not, however, challenge the fundamental correctness of the central thesis of evolution.

From all we know about the state of the Earth 3 to 4 billion years ago and what we know about the complexity of the building blocks of life — DNA, RNA, amino acids, sugars — no entirely plausible hypothesis for the spontaneous origin of life has been found. But this does not mean that supernatural activity is the only possible explanation.

A common argument against biological evolution is that the theory contradicts the second law of thermodynamics. The second law says that disorder, or entropy, always increases or stays the same over time. How then can evolution produce more complex life forms over time? The answer is that the second law is only valid in closed systems with no external sources of energy. Since the Earth receives continual energy from the Sun, the second law does not apply.