Sunday, 18 March 2018

Chromosome 2 and Human Evolution - a new series of educational videos by Darrel Falk

Darrel Falk, emeritus professor of biology at Point Loma Nazarene University past president of BioLogos has created a three part video series on human chromosome 2, its origin from a fusion of two chromosomes homologous to ape chromosomes 2p and 2p, and how this provides evidence for common descent. In addition, the video series also answers objections as to how the first individuals with such a fused chromsome could have survived, how the fused chromosome became fixed in the ancestral gene pool, and a few theological observations on the subject. Falk is uniquely placed to comment both as a Christian and as a biologist whose research career included the subject of chromosomal breakage.

Each video is short at under ten minutes, but is quite comprehensive in its subject matter. I cannot recommend them enough for the person wishing to understand why we know chromosome 2 is the product of a fusion event, and why it provides such strong evidence for common descent.

I have included the three references cited in the second video below for those interested in following up the subject. In addition, the remaining references contain some of the classic papers on the subject, dating back to the 1980s, as well as commentary on the subject debunking special creationist attempts to explain away the evidence.

Friday, 16 March 2018

Always verify your references...

Over the life of this website, I have critiqued a number of Christadelphian anti-evolution lectures and articles. Without exception, all of them were characterised by errors of fact, logical fallacies, and a tendency to recycle long-refuted special creationist attacks on evolution. Having debunked a considerable number of these anti-evolution articles, and discovered that subsequent attacks on evolution merely recycled the same points refuted a thousand times, [1] I have opted not to publish any further critiques if only because there is little point in slapping a new title on an old refutation.

This doesn't mean that other Christadelphian evolutionary creationists have likewise stopped publishing critiques of bad anti-evolution articles. Recently, the author of the excellent The Fourth Conversation has written a detailed critique [2[ of an anti-evolution lecture by an Australian Christadelphian evolution denialist, ably pointing out its many errors. Given this, there is no point in duplicating his excellent refutation. However, I would like to expand on one point in order to highlight one of the fundamental problems blighting fundamentalist attacks on evolution, namely a failure to verify references. After all, if the sources on which you rely to make your argument are flawed, your argument is dead in the water.

Thursday, 15 March 2018

The 7300 year old origin of sickle cell anaemia: genetic disease before Adam.

A recent paper by Daniel Shriner and Charles Rotimi in The American Journal of Human Genetics [1] has weighed in on the question of the origins of the genetic mutation that causes sickle cell disease. Sickle cell anaemia is a classic example of human evolution. While the disease is markedly debilitating, it persists as those who are carriers for the disease are relatively protected against malaria compared with those who do not carry the gene.

There are five sickle cell haplotypes, and it has been assumed that each haplotype originated from independent occurrences of the mutation. Shriner and Rotimi argue, based on an analysis of genetic data from 156 carriers of sickle cell disease that the mutation had a single origin around 7300 years ago. While we are in no need of further evidence to show that it is impossible for the entire human race to have originated exclusively from two people 6000 year ago, articles such as this not only serve to underline this fact, but also show why believers such as myself who work in medicine and the life sciences regard common descent and large-scale evolutionary change as facts as real as a spherical earth.

Friday, 2 March 2018

A 430,000 year old murder mystery - death and violence before Adam.

The first murder described in the Bible is that of Abel, slain by his brother Cain. However, as the fossil record attests, humans have been killing each other for hundreds of thousands of years before this, well before the emergence of our species Homo sapiens. That human death predated the earliest possible date for Adam is impossible to deny as the fossil record bears eloquent testimony both to the antiquity of the human lineage and the stark fact of human death stretching back well before 6000 years ago. More to the point, the archaeological evidence of violent acts committed by humans against each other, as well as evidence of deliberate compassion shows that the contradictory mix of mercy and violence that characterise human nature stretches back well into the past, and can be found even among other hominin species.

Tuesday, 13 February 2018

Humanity before Adam. A Heaping Helping of Hominids.

As Evangelical geologist Davis Young noted in a 1995 paper for Christian Scholar's Review, if the evidence in Genesis 4 allows us to date Adam to the Neolithic Revolution in the ancient Near East, then the earliest possible date for Adam is around 10,000 years ago. The problem that confronts Biblical literalists is that the fossil evidence for anatomically modern human beings stretches back around 300,000 years, meaning that Adam simply could not have been the first anatomically modern human being to exist. As a reminder to Christian fundamentalists who have still yet to see this evidence, here's a photo review of the anthropological record for Homo sapiens stretching back from 10,000 years ago to the earliest known Homo sapiens remains 300,000 years ago.

Wednesday, 7 February 2018

Adam in Innocence

The dogmatic assertion that human death was unknown prior to Adam’s sin is of course incorrect. The fossil record shows that Homo sapiens has been living and dying on this planet for at least 300,000 years, with the genus Homo stretching back at least two million years ago. Add to that the fact that the human genetic evidence confirms the human race has never been smaller than a few thousand, and the belief that the entire human race descended exclusively from two people living six thousand years ago is one that can only be maintained in defiance of the overwhelming evidence against it.

Given this, it is disappointing to see conservative Christians more concerned with privileging their traditional interpretations of the Bible and their credal statements than in honestly engaging with this evidence. This is particularly the case when attempts are made to make one particular interpretation normative for an entire faith tradition. As anyone familiar with Christian theology would be aware, the number of interpretations of contested passages such as Romans 5:12 and the diversity of opinion on what happened to Adam after his sin show that caution and humility, rather than bold assertion and sanctioning of alternative views are definitely advisable.

Thursday, 25 January 2018

Evolution is not crocodiles evolving into ducks. Debunking a common special creationist error

In my experience, it's a rare special creationist who knows anything about evolutionary biology, which of course makes their criticisms immaterial. After all, if you want your criticisms of something to be taken seriously, you first need to demonstrate that you know that subject intimately. Otherwise, no one will take anything you say seriously.

One of the most common special creationist errors is to assert that they will only accept evolution if they see one animal evolving into another. This error betrays a profound lack of understanding of the rudiments of evolutionary biology which states that it is populations that evolve, rather than individuals. Pokémon evolution is not the same thing as biological evolution.