Evidence for evolution 5.1

There are different types of evidence which support the theory of evolution, from fossils to selective breeding. This topic covers a range of evidence and some of the concepts related to inheritance, natural selection and evolution. 


Key words

Learn and test your biological vocabulary for 5.1 Evidence for evolution using these flashards

Clean sweep - quick revision through the whole topic

These slides summarise the essential understanding and skills in this topic. 
They contain short explanations in text and images - good revision for all students.

Read the slides and look up any words or details you find difficult to understand.

Skills and applications

A short video explanation is planned here to show how to:

  • Compare and contrast the pentadactyl limb of mammals, birds, amphibians and reptiles.
  • Describe how each limb structure is adapted to each different method of locomotion.

Revision summary list for 5.1 Evidence for evolution

  • A change in the heritable characteristics of a species is evolution.
  • Evidence for evolution comes from
    • the fossil record.
    • Selective breeding of domesticated animals
    • "Adaptive radiation" can explain similar structures with different functions.
    • Isolated populations can produce separate species by divergent evolution.
    • Continuous variation across the geographical range of related populations matches the concept of gradual divergence.

Skills (can you ....)

  • Describe how the dark bark leads to the development of melanistic insects in polluted areas.
  • Compare and contrast the pentadactyl limb of mammals, birds, amphibians and reptiles.
  • Describe how each limb structure is adapted to each different method of locomotion.

Revision mindmaps

These diagram summaries cover the main sections of topic 4.3 Carbon cycle.
Study them and draw your own list or concept map, from memory if you can.

 

Review questions

This is a self marking quiz containing questions covering the topic outlined above.
Try the questions to check your understanding.

1

Which of the following statements is not true about Evolution?

"A change in the heritable characteristics of a species" is evolution.
Most frequently this is a gradual cumulative change.

Changes to individual organisms during their lifetime are not evolution, as the change has to be heritable.
Evolution occurs a the species level because individuals survive or die which changes the composition of the members of the species.

2

Which of the points below provide evidence in support of evolution?

  1. The fossil record.

  2. Selective breeding of food crops.

  3. The wings of birds and bats

  4. Radiation studies

Evidence for evolution in this list comes from;

  • The fossil record.
  • Selective breeding of food crops and domesticated animals.
3

What might be expected to happen if two populations of a species of snail are separated by a river which has very different environmental conditions on each bank, for example a woodland and a golf course?

If the are different selection pressures in the two environments, then snails will be affected by different natural selection. This is divergent selection.

4

Lake Malawi has a surface area of almost 30 000 km2 and is home to 1000 species of Cichlid fish.

The diagram of Cichlid fish varieties illustrates a continuous variation in their features across the geographical range of the lake.

It is understood that all but five species are descendants of a single original colonist species?

What is the name of the process which forms this sort diversity?

Continuous variation across the geographical range of related populations matches the concept of gradual divergence.

5

The image below shows adaptations in the wings of modern insects.

There is evidence that ancestors of all these insects had two pairs of wings.

What is the biological term for structures like these?

All the insects share the feature of having 2 pairs of 'wing-like' structures although there are differences in each animal.

This suggests that they all shared a common ancestor, with 2 pairs of wings.
6

What is the best description of selective breeding?

Selective breeding provides evidence for evolution because it shows that when a breeder chooses the animals for the breeding programme which have specific features, the offspring have more of these features.

7

What natural process causes the increase in frequence of the melanistic form of the Peppered moth if pollution causes the vegetation it lives on to be covered in smoke and become darker?

Natural selection causes an increase in the number of dark moths because the birds which eat the moths cannot see the dark forms so easily, as they have better camoflage in polluted environments.

Total Score:

Revision fun activity

Everyone needs a bit of fun while they revise. Try this Evidence for evolution arcade game.
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