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?

Give three reasons why Darwin's theory of evolution was only gradually accepted: Explain Lamarck’s theory of 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? 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. Body covering How offspring are produced How it breathes Warm or cold blooded Where it lives Fish cold Amphibians Fill in the gaps in the table below.

Reptiles Birds Mammals Moist skin Lays eggs with leathery shell cold Land Lungs Land

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 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 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 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. 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 Fish Amphibians Fill in the gaps in the table below.

Reptiles Birds Mammals 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 Body covering How offspring are produced How it breathes Warm or cold blooded Where it lives Scales Lays soft eggs Gills cold Water Moist skin Lays eggs in jelly Lungs, gills, skin cold Lives part of its life in water Scales Lays eggs with leathery shell Lungs cold Land Feathers Lays eggs with hard shells Lungs warm Land Fur Gives birth to live young Lungs Warm Land