1. What was the principle behind Darwin's theory of evolution?
What sort of time period does evolution normally happen over?
What can cause it to happen more quickly when there is a change in the environment?
Explain Lamarck’s theory of evolution.
Give three reasons why Darwin's theory of evolution was only gradually accepted:
1.8 Evolution
Outline the key principles of natural selection,
Use the evolutionary tree diagram on the right to answer the following questions:
Which group of organisms are most closely related to Birds?
Are fish or mammals more closely related to dinosaurs?
Fill in the gaps in the table below.
Fish
Amphibians
Reptiles
Birds
Mammals
Body covering
Moist skin
How offspring are produced
Lays eggs with leathery shell
How it breathes
Lungs
Warm or cold blooded
cold
cold 
Where it lives
Land
Explain how a mutant gene that allows a group of people who live in the Philippines to develop gills could result in all humans being able to breathe under water in 100 years time.

2. What was the principle behind Darwin's theory of evolution?
All species evolved from simpler life forms that first developed more than 3 billion years ago
What sort of time period does evolution normally happen over?
Millions of years
What can cause it to happen more quickly when there is a change in the environment?
Advantageous mutation
Explain Lamarck’s theory of evolution.
Variation between organisms within a species is due to changes acquired during their lifetime
These acquired characteristics (not genes) are passed on.
Give three reasons why Darwin's theory of evolution was only gradually accepted:
Challenged religion – idea that god made all living organisms
Insufficient evidence at time
Mechanism of inheritance not discovered until 50 years later
1.8 Evolution
Outline the key principles of natural selection,
Organisms within a species show variation due to mutation causing differences in their genes
Some of these genes will give characteristics that increase changes of survival
These organisms are then more likely to breed and pass these genes on
Use the evolutionary tree diagram on the right to answer the following questions:
Which group of organisms are most closely related to Birds? Dinosaurs
Are fish or mammals more closely related to dinosaurs? Mammals
Fill in the gaps in the table below.
Fish
Amphibians
Reptiles
Birds
Mammals
Body covering
Scales
Moist skin
Feathers
Fur
How offspring are produced
Lays soft eggs
Lays eggs in jelly
Lays eggs with leathery shell
Lays eggs with hard shells
Gives birth to live young
How it breathes
Gills
Lungs, gills, skin
Lungs
Warm or cold blooded
cold
cold 
warm
 Warm
Where it lives
Water
Lives part of its life in water
Land
Explain how a mutant gene that allows a group of people who live in the Philippines to develop gills could result in all humans being able to breathe under water in 100 years time.
Global warming causes flooding so less land
Mutant gene = can live in water so more like to survive
More likely to pass genes on
Offspring more likely to survive
Eventually everyone has gills