Funding for this site is provided by readers like you.
Evolution and the brain
Sub-Topics
Our Evolutionary Inheritance

Linked
HelpLien : débat contre un créationnisteLien : Evolution and CreationLien : Evolution & Providence
Lien : Evolution vs. Creationism Lien : Evidence of EvolutionLien : The General Anti-Creationism FAQLien : Evolution and Creation
Lien : Livre : Et Dieu dit : « Que Darwin soit ! », S.J. Gould, seuil, 2000.Lien : Le second débat Barrette-Tisdall sur l'origine de la vie a soulevé les passions sur le campusLien : Créationnisme et ChristianismeLien : Creationism vs Science
Lien : Five Major Misconceptions about EvolutionLien : 15 Answers to Creationist Nonsense Lien :La vigilance critique envers le créationnisme
Researcher
Chercheur : Ernst Mayr and the Evolutionary SynthesisChercheur : Francisco J. Ayala
Histoire : Évolution et religionHistoire : Timeline: Monkey TrialHistoire : La croisade contre Darwin reprend au Tennessee 1/2
Original modules
Tool Module: What Is Evolution?What Is Evolution?
Tool Module: The Connection between Ontogeny and Phylogeny The Connection between Ontogeny and Phylogeny

When creationists say that there are no transitional fossils to support the theory of evolution, they are implicitly assuming a kind of evolution that always takes place little by little. This view of evolution is inherited from Darwin, who did conceive of evolution as a process that occurs gradually.

But since Gould and Eldredge posited their theory of punctuated equilibria, we know that evolution can occur in other ways. Indeed, some species can evolve very rapidly over periods that are brief in geological terms, followed by long periods of stagnation. Considering the rarity of the conditions necessary for fossilization, we can understand why there will necessarily be some “"gaps" in the fossil record. That in no way invalidates evolution as we understand it today, especially after the important contribution made by Gould and Eldredge.

Their theory of punctuated equilibria does not constitute a complete paradigm shift, but it does let scientists revisit Darwin's initial intuitions about the process of evolution, intuitions that some thinkers were too quick to freeze into dogma.

Tool Module: Gradual Evolution or Punctuated Equilibria?Tool Module: Darwin's Natural Selection
Chercheur: Stephen Jay Gould: le héros de l'évolutionChercheur : Stephen Jay Gould Archive
CREATIONIST ATTACKS ON EVOLUTION

For the past two decades, the United States has been subjected to the growing influence of “"creationists" who believe that the story of creation as told in the Bible must be taken literally... in other words, that the universe was created in six days, scarcely 6 000 years ago.

 

Aside from the fact that the fundamentals of creationism are contradicted by all the currently available scientific data, many of the criticisms that creationists commonly direct against the theory of evolution reflect a misunderstanding of what evolution actually is.

Here are some of the most common creationist criticisms of evolution, along with the counter-arguments based on an accurate understanding of this subject.

Evolution has never been observed.”

Evolution is basically defined as a change in the gene pool of a species over time. There are myriad examples of this phenomenon, such as bacteria that develop resistance to drugs or insects that develop resistance to pesticides over a short period of time. The emergence of new species has also been observed both in the laboratory and in nature, especially among fruit flies. And even if we did not have these direct observations, the theory of evolution has enabled us to make predictions regarding the fossils of species that have now disappeared, and in terms of both comparative anatomy and geographic distribution, these predictions have proven accurate in a multitude of cases.

Lien : Observed Instances of Speciation

“Evolution violates the second law of thermodynamics.”

This law states that the entropy (or “"disorder") in a closed system can only increase. Creationists simplify this law by stating that order (and hence life) cannot have emerged from the disorder of the inanimate things found on Earth. But creationists thereby ignore one major fact: the Earth is not a closed system. It constantly receives energy from the Sun and sends energy back out into the universe in such forms as infra-red radiation. In an open system like this, order (or “"negentropy") can be created locally provided that energy is degraded on a larger scale, which is the case for the organisms living on Earth. In any case, the tendency for matter to organize itself is observed even in inanimate things: snow flakes, sand dunes, tornadoes, and lightning bolts are several good examples.

There are gaps (missing links) in the fossil record.”

First of all, there are some impressive sequences of fossils that demonstrate the most minute steps in the transitions from reptiles to mammals and from ancient primates to ancient humans, for example. The presence of gaps in no way discredits the theory of evolution. Such gaps have many possible causes, such as erosion of fossil-bearing formations, the rareness of conditions conducive to fossilization, and the fact that speciation can occur in a small population or a limited area, or very rapidly (see sidebar).

 

 

“The theory of evolution is based on the idea that life emerged solely by chance.”

Chance, in the form of the random mutations that are the source of genetic diversity, does indeed play an essential role in evolution. But to say that evolution is based solely on chance is to badly misunderstand the equally fundamental role played by natural selection. It is only by favouring some genetic variants over others that organisms better adapted to their environment can evolve.

The final argument that creationists marshal to try to undermine the theory of evolution is what they call “"intelligent design". It is based on a more subtle line of reasoning: that the living world is so complex that only an intelligence outside our universe could have planned it down to the last detail. But here again, a proper understanding of the theory of evolution would seem to obviate the need to posit an intelligent design or a “"higher consciousness".

  Presentations | Credits | Contact | Copyleft