Uncertainty in Uncertainty in BiologyBiology

At least we can be At least we can be certain that evolution is certain that evolution is true. These two have true. These two have told us.told us.

At least we can be At least we can be certain that evolution is certain that evolution is true. true.

Many scientists disagree! Also it depends Many scientists disagree! Also it depends on what you mean by “Evolution”! Causes on what you mean by “Evolution”! Causes confusion!confusion!

1.1.““Macro” evolution by spontaneous natural Macro” evolution by spontaneous natural process – order from chaosprocess – order from chaos

2.2.““Macro” evolution guided by designer Macro” evolution guided by designer Creation not requiring an evolution processCreation not requiring an evolution process

– In other words Darwinian evolution is just In other words Darwinian evolution is just one of several hypothesis or models to one of several hypothesis or models to explain the untestable pastexplain the untestable past

At least we can be At least we can be certain that evolution is certain that evolution is true. true.

1.1. Also as scientists we need to Also as scientists we need to distinguish between “Macro” distinguish between “Macro” and “Micro” evolution.and “Micro” evolution.

At least we can be At least we can be certain that evolution is certain that evolution is true. true.

1.1. Macro evolutionMacro evolution e.g. humans originated from lifeless e.g. humans originated from lifeless

chemicals! chemicals!

2.2. Micro evolutionMicro evolution e.g. Peppered moth adapts to e.g. Peppered moth adapts to

environmentenvironment BUT – it is still a moth!! (so why is it BUT – it is still a moth!! (so why is it

used as evidence of macro evolution in used as evidence of macro evolution in text books?!)text books?!)

At least we can be At least we can be certain that evolution is certain that evolution is true. true.

Amongst the scientific community there is a great deal of scientific scepticism of Neo-Darwinism: Public Statement has currently over 700 signatures

Of these a significant number are “Young Earth” scientists

They used science to They used science to demonstrate it.demonstrate it.

1.1. Have a hypothesis.Have a hypothesis.

2.2. Make observations and Make observations and measurements.measurements.

3.3. Make suggested conclusions Make suggested conclusions based on data.based on data.

4.4. Peer review.Peer review.

5.5. Reject or accept hypothesis.Reject or accept hypothesis.

We can be certain We can be certain because:because:

The fossil record.The fossil record.

Fossils give us Fossils give us intermediate forms (fish intermediate forms (fish to tetrapod transition).to tetrapod transition).

Fossils give us Fossils give us intermediate forms (fish intermediate forms (fish to tetrapod transition).to tetrapod transition). Darwin’s EnigmaDarwin’s Enigma

– ““The geological record is extremely imperfect The geological record is extremely imperfect and this fact will to a large extent explain why and this fact will to a large extent explain why we do not find intermediate varieties, we do not find intermediate varieties, connecting together all the extinct and connecting together all the extinct and existing forms of life by the finest graduating existing forms of life by the finest graduating steps. He who rejects these views on the steps. He who rejects these views on the nature of the geological record, will rightly nature of the geological record, will rightly reject my whole theory.”reject my whole theory.”

– Charles Darwin, Charles Darwin, The Origin of The Origin of SpeciesSpecies…….…….

Fossils give us Fossils give us intermediate forms (fish intermediate forms (fish to tetrapod transition).to tetrapod transition).““fossils such as fossils such as AcanthostegaAcanthostega are regarded are regarded

by some evolutionary palaeontologists as by some evolutionary palaeontologists as ‘missing links’ not because they are, but ‘missing links’ not because they are, but because they are believed to be. As because they are believed to be. As Patterson says, it is ‘in the mind’, because Patterson says, it is ‘in the mind’, because ‘missing links’ are a philosophical ‘missing links’ are a philosophical necessity—to somehow provide ‘proof’ for necessity—to somehow provide ‘proof’ for their evolutionary faith”their evolutionary faith”

Andrew Snelling BSc (Hons), PhDAndrew Snelling BSc (Hons), PhD

Artificial SelectionArtificial Selection

Artificial SelectionArtificial Selection

A Pigeon

You get the picture!

And…

……

Anoth

er

Pigeo

n

erm!...is it a

Pigeon by any chance?

Another Pigeon

Big Dog

Little Dog They are both still dogs!

All life has things in All life has things in common.common. DNA (the universal code in living DNA (the universal code in living

organisms)organisms) Amino acidsAmino acids ProteinsProteins

All life has things in All life has things in common.common. Indeed…..much as a designer may Indeed…..much as a designer may

utilise a common platform in his utilise a common platform in his designs, so nature seems to have designs, so nature seems to have been created using a common set been created using a common set of genetic instructions.of genetic instructions.– Why not re-use certain proteins in Why not re-use certain proteins in

different species…that makes perfect different species…that makes perfect sense from an intelligent design point sense from an intelligent design point of view?of view?

Vestigal organs.Vestigal organs.

What is the appendix for?What is the appendix for? Why have we still got it?Why have we still got it? Is there selection pressure to Is there selection pressure to

have a larger one?have a larger one?

Vestigal organs.Vestigal organs.

‘‘vestigial’ vestigial’ : an organ that once was : an organ that once was useful in an animal’s evolutionary useful in an animal’s evolutionary past, but that now is useless or very past, but that now is useless or very close to useless. close to useless.

The list of vestigial organs in The list of vestigial organs in humans has shrunk from 180 in humans has shrunk from 180 in 1890 to 1890 to 0 0 in present day.in present day.

– Bergman and Howe, 1990Bergman and Howe, 1990

Vestigal organs.Vestigal organs.

So what of the apparently useless So what of the apparently useless appendix?appendix?

The appendix is part of the immune The appendix is part of the immune system, strategically located at the system, strategically located at the entrance of the almost sterile ileum entrance of the almost sterile ileum from the colon with its normally from the colon with its normally high bacterial contenthigh bacterial content

Predictable Predictable BiogeographyBiogeography Marsupial distribution – why?Marsupial distribution – why?

Out-competed everywhere else Out-competed everywhere else by placental mammalsby placental mammals

Evolution can be Evolution can be observed in the process observed in the process of speciation.of speciation. E.g. Drosophila E.g. Drosophila

Imperfections – why Imperfections – why would a creator produce would a creator produce imperfect organismsimperfect organisms E.g. Blind spot in the eye.E.g. Blind spot in the eye.

Imperfections – why Imperfections – why would a creator produce would a creator produce imperfect organismsimperfect organisms

Eye often used (by Dawkins for Eye often used (by Dawkins for example) to argue that there example) to argue that there can’t be an Intelligent Designer can’t be an Intelligent Designer since the eye has a flawed since the eye has a flawed design!design!

However….it is merely ignorance However….it is merely ignorance of eye’s physiology that leads to of eye’s physiology that leads to such a conclusion!such a conclusion!

Imperfections – why Imperfections – why would a creator produce would a creator produce imperfect organismsimperfect organisms

The blind spot does not reduce vision quality.The blind spot does not reduce vision quality.

Each eye sees a slightly different visual field; large Each eye sees a slightly different visual field; large areas overlap. Each eye has a blind spot where the areas overlap. Each eye has a blind spot where the optic nerve passes through the retina to reach the optic nerve passes through the retina to reach the brain, this blind spot falls on a different place in each brain, this blind spot falls on a different place in each retina.retina.

Info from both eyes is then combined so that these Info from both eyes is then combined so that these visual blind spots are not normally perceived. visual blind spots are not normally perceived. Therefore because the other eye fills in the gap, Therefore because the other eye fills in the gap, special tests are normally required to even notice it. special tests are normally required to even notice it.

((He and Davis 2001He and Davis 2001). ).

Intelligent Design: Intelligent Design: Irreducible ComplexityIrreducible Complexity

• 40 different complex protein components

• Absence of any one of these causes the rotor to fail!

• Therefore all parts will have had to evolve simultaneously in order to produce a functional advantage to the bacteria….unlikely!Therefore an Intelligent Designer

needed.