EVOLUTION YEAR 10 BIOLOGY Survival of the fittest!

LESSON 1 INTRODUCTION AND HISTORY OF EVOLUTION Goal: To compare two theories of evolution (Darwin and Lamarck) Glossary Words: Evolution, Natural selection, Variation, Characteristic. Success Criteria: Defined Glossary Words Completed tasks A and B

SCIENTIFIC CLASSIFICATION  Scientists classify all living things into one of 5 Kingdoms.  Phenotype (observed characteristics) are used for classifying organisms. Scientific name: Genus & Species

COMMON ANCESTOR  All living things have descended from a common ancestor (LUCA)  Some species, genus, family, order, class, phylum and kingdoms are more closely related than others. Phylogenesis: Study of evolutionary relationships. The evolutionary development and diversification of a species or group of organisms, or of a particular feature of an organism.

All living things share similarities and differences! Some organisms share more similarities than others!

INTRODUCING EVOLUTION  Ever wondered why there is so much biodiversity of life on earth?  Ever wondered how Birds came to fly? Fish came to swim or Giraffes came to have long necks?  How are we similar and different to our long lost cousins the Apes? The THEORY OF EVOLUTION explains how all life on earth came to exist. Evolution is a process of gradual change in the characteristics of living things that has occurred over millions of years and is still going on today [Change over time]. Organisms change over time because it is advantageous for their survival. Survival of the fittest!

THEORY OF EVOLUTION (NATURAL SELECTION) This process of evolution is known as NATURAL SELECTION and can be summarised in five points: 1 There is variation between organisms. 2 The numbers of natural populations remain fairly constant even though they reproduce in far greater numbers. 3 There is a struggle for survival. 4 Some variations help organisms survive. Organisms with less favourable characteristics die out. 5 The variations with survival value are passed on to the following generations, so over millions of years species become better adapted to their environment. Charles DARWIN inferred that some variations (differences) helped organisms survive and reproduce. Favourable characteristics would be passed on and over time the group of organisms would gradually change.

SO WHY DO GIRAFFES HAVE LONG NECKS? If we use the giraffe as an example: Darwin would say: There is variation among giraffes, some having longer necks than others. The shorter- necked giraffes would die out when food in the lower branches of trees ran out. The longer-necked ones could reach food higher up and would have a greater chance of surviving and passing on long necks to their offspring. So over time the giraffe population would all come to have long necks. Long necked Girraffes are better adapted for survival. Evolution by Natural selection is survival of the fittest! Favorable characteristics that enable the organism to survive are passed on to the offspring (natural selection)

THEORY OF EVOLUTION Your Task: 1.Read the information resource on the history of evolution 2.Complete part A and part B. 3.Finish off at home before the next lesson (Wednesday) You will be asked to role play your accounts!

REFLECTION T-P-S What is the difference between the theory of evolution from Darwin and Lamarck’s perspectives?

REFLECTION T-P-S What is the difference between the theory of evolution from Darwin and Lamarck’s perspectives? DarwinLamark Organisms better suited to their environment survived to reproduce. These new characteristics were passed to offspring Organisms acquired traits by using their bodies in new ways These new characteristics were passed to offspring