Evolution Basics

Published on October 30, 2018

Written by former BioLogos Fellow of Biology Dennis Venema, this series of posts is intended as a basic introduction to the science of evolution for non-specialists.

Evolution as a Scientific Theory

The goal of this course is straightforward: to provide evangelical Christians with a step-by-step introduction to the science of evolutionary biology.


How Darwin Developed His Theory

These lines of evidence would later prod him to consider the possibility that species arise through a natural process of gradual change over time, rather than...

Artificial Selection and the Origins of the Domestic Dog

We are beginning to see the genetic underpinnings of artificial selection at a genome-wide level, and the results are absolutely in keeping with Darwin’s ideas...


Natural Selection and the Human Lineage

I’ve often encountered the misconception among non-biologists that mutations are always harmful, or always remove functions and information.


The Basis of Heritable Variation

Taken together, the properties of DNA match what we observe in nature: faithful reproduction of form, but not perfect reproduction of form.


From Variation to Speciation

…in small populations, drift can have a large impact on allele frequencies from one generation to the next. In large populations, natural selection predominates...


Genomes as Ancient Texts

…while errors made by human scribes tend preserve a meaning of some kind...DNA replicating enzymes do not check to see if meaning (i.e. function) is preserved as they copy.


Incomplete Lineage Sorting

If a gene has variation in a population undergoing speciation events, it is expected that some of the time it will assort with a pattern that does not match the species pattern...


Homoplasy and Convergent Evolution

Homoplasies can be as simple as single DNA monomer changes, or as complex as the independent reorganization of multiple systems with numerous genes and body parts to converge on a solution.



Moths that are merely using a warning sound to advertise their toxicity emit signals in a pattern that does not produce interference with bat echolocation...


The Cambrian Diversification and Assembling Animal Body Plans

All living arthropods have a suite of defining characteristics such as a hard external skeleton (exoskeleton), specialized body segments, and specialized appendages. While these...


Assembling Vertebrate Body Plans

…the probability that any given fossil species is a direct ancestor of a modern-day species is vanishingly small. Fossilization is a highly infrequent event...


Evolution Basics: The Placental Revolution

The placental diversification in the Paleogene is highly interesting from an evolutionary standpoint since niches that were vacated by reptiles were in many cases filled by placental...


Evolution Basics: From Primate to Human

For many years, it was unclear if humans were more closely related to chimpanzees or to gorillas, but full genome sequences allowed us to resolve the issue.


Mitochondrial Eve and Y Chromosome Adam

Wait just a second, you say–isn’t the evidence strong that modern humans descend from a population that has never numbered less than about 10,000 individuals...


How Language Evolution Helps Us Understand Human Evolution

Language evolution is in fact one of the better analogies for biological evolution, in that it forces one to think of change in the context of a population over time.


Paleogenomics and the Tangled Web of Human Speciation

Amazing as it sounds, in the proper conditions DNA can persist inside bones and teeth for tens (or even hundreds) of thousands of years.


At the Frontiers of Evolution: Abiogenesis and Christian Apologetics

It is not a surprise that a scientific theory will address areas that are poorly understood: indeed, it is expected that theories, as they expand, will naturally have a frontier...


At the Frontiers of Evolution: Contingency vs. Convergence

This series of posts is intended as a basic introduction to the science of evolution for non-specialists. You can see the introduction to this series here. In this post we discuss the debate between paleontologists Stephen Jay Gould and Simon Conway Morris over whether evolutionary history is primarily shaped by chance events (i.e. by contingency) or through repeatable events (i.e. by convergence).

Is Evolution a Purposeless Mechanism?

Many Christians view evolution as a wasteful, random, inefficient process, which seems at odds with the work of a sovereign God. But is this characterization appropriate?

Fearfully and Wonderfully Made

Some of the Christian objections to evolutionary creation come from a misunderstanding of what the Bible means when it says “God created."

Speaking the Truth in Love

There is a need to speak out truthfully about evolution, but love and a desire for Christian unity must be foremost when doing so.