Issue 5 | January 2007

Illustration showing skeletons of apes and man

Evolution

***Articles reviewed and updated December 2014***

“Nothing in biology makes sense except in the light of evolution,” wrote biologist Theodosius Dobzhansky in 1973. Today, the general principles of Darwinian evolution have been widely accepted by many, but some remain sceptical. This issue, published at the height of the intelligent design debate, seeks not to explain why evolution is ‘true’ (indeed, many other publications do that), but rather explain the concept of evolution and explore why, despite the evidence, not everyone believes it.

Browse through the individual articles and check out our activities and lesson ideas. This issue was first published in 2007; in 2014, all of the individual resources were reviewed and updated for accuracy and currency. Please do note, however, that the PDF of the original 2007 issue has not been updated.

The big idea

The origins of modern evolutionary thinking

“Nothing in biology makes sense except in the light of evolution”

How Darwin changed the world

Charles Darwin put forward a theory of evolution by natural selection – but he was not the only person to come up with such an idea

The evidence for evolution: in images

Darwin brought together many lines of evidence to support his theory. Since his time, other studies have added to the weight of evidence for evolution

Caught in a drift

A random process of drift can also change the genetic make-up of a species

Cultural evolution

Genes aren’t the only way information can be passed on

Mechanisms of evolution

The discovery of genes provided a mechanism for heredity and a way to explain how natural selection operated

Rock stars: the fossil record comes to life

Fossils allow us a glimpse of the past

Extinction events

Occasionally the Earth experiences mass extinctions, where catastrophic environmental change wipes out huge numbers of living things

In the beginning...

Creation myths are common throughout human culture

One big family

Meet your (distant) cousin

All humans are related to one another – and to all other living organisms

Tree of life

Living things fall into three major divisions: Bacteria, Archaea and Eukarya

Convergent evolution

Evolution usually works by diversification, but sometimes a similar solution is reached by different routes

Building family trees

DNA sequence analysis is now used to build family trees

Whose gene is it anyway?

Genes are widely shared but adapt to take on new roles in different organisms

Taxing taxonomy

Taxonomy provides a way of characterising living things and documenting family relationships

Are humans different?

Are we different from the rest of the natural world?

Close cousins

Chimpanzees are our closest relatives, and genome sequence comparisons are beginning to identify the key genes that distinguish us from them

Evolution in action

Speciation

Darwin called his book ‘On the Origin of Species’, but what exactly does the origin of species mean?

Are humans still evolving?

Are we still subject to natural selection?

Pathogen evolution

Organisms that cause disease illustrate the power of evolution

Seeing evolution

It is possible to see evolution in action – often because of human interventions

Creating variation

Evolutionary change by natural selection (or genetic drift) requires variation in DNA. Where does this variation come from?

Letters begin

Is DNA (or RNA) sequence the only way information can be encoded and passed on from generation to generation? The short answer is no

We all stand together

In symbiotic relationships organisms do not evolve independently but evolve as a pair – or even as a group

Directed evolution

For thousands of years humans have tried to harness the best of nature by modifying crops, animals and even decorative plants or flowers

Cancer: the selfish cell?

The emergence of cancers in the body is a form of natural selection

Micro- or macro-

Genetic changes create variation. But do they really create new species?

Unanswered questions

Design flaws

Our bodies are far from perfect – and evolution is to blame

Origins of life

This article, first published in our ‘Evolution’ issue, asks: how did life on Earth get going?

Did the designer do it?

Some people find the idea that natural processes alone created complex life too far-fetched

Brains and behaviour

Can evolutionary ideas explain human behaviour?

Balancing selection

Natural selection should weed out alleles with a harmful effect from the gene pool. So why do some still hang around?

Social impact

In Darwin’s day

Charles Darwin may be the name associated with evolution, but he was not alone in his radical thinking

Social Darwinism

Natural selection operates in a biological context. Others have applied it to the way people and society behave – often with disastrous consequences

One for all, all for one?

If natural selection favours survival of the fittest, and genes are selfish, why do we ever help one another?

Post-human world

What does evolution have in store next for Homo sapiens?

Memes

Passing cultural information from person to person

Applying evolution

If you enjoy studying evolution, there are many career fields you could consider going into

Evidence and belief

Darwin today

Nowadays, the theory of evolution satisfies most academics, although they argue over the finer details. The public is less convinced...

But it’s only a theory

The theory of evolution shows how science operates

Science in the real world

Science is logical and objective – mostly. But let’s get real…

Science and religion

Is conflict between science and religion inevitable?

A lot like us

Humans tend to see things from a human perspective. Does this distort our view of the world?

The power of prayer

Do religious beliefs provide a selective advantage?

The evidence for evolution: in images

Darwin brought together many lines of evidence to support his theory. Since his time, other studies have added to the weight of evidence for evolution

Historical aspects

The growing human family

The human genome contains traces of two ancient relatives – Neanderthals and Denisovans

In Darwin’s day

Charles Darwin may be the name associated with evolution, but he was not alone in his radical thinking

Social Darwinism

Natural selection operates in a biological context. Others have applied it to the way people and society behave – often with disastrous consequences

The origins of modern evolutionary thinking

“Nothing in biology makes sense except in the light of evolution”

Disease

The evolution of Ebola

Could Ebola evolve and become an even greater threat to humankind?

Cancer: the selfish cell?

The emergence of cancers in the body is a form of natural selection

Balancing selection

Natural selection should weed out alleles with a harmful effect from the gene pool. So why do some still hang around?

Real Voices interviews

Real Voices interview: Bryan, Usamah and Kanwaljit

Meet three people from Buddhist, Islamic and Sikh backgrounds and read their thoughts on evolution

Real Voices interview: Michael Reiss

Meet Michael, who provides a Christian perspective

Activities and lesson ideas

Survival of the fittest: Evolution quiz

Can you distinguish a Darwinian idea from a Lamarckian one? A eukaryote from a prokaryote? Take our quiz to see just how ‘evolved’ you are in your understanding of this topic

Lesson idea: comparing natural selection, ID and creationism

How well do intelligent design, creationism and natural selection compare as scientific theories?

Further resources and activities on evolution

The Wellcome Trust has funded many other organisations to produce the following activities and resources to help engage and educate young people about evolution

Fast Facts

Each issue of 'Big Picture' comes with a sprinkling of Fast Facts, fascinating snippets of information on the topic covered.

Browse through all of our Fast Facts indexed by topic