BTY100-Lec#1.2 Evolution-An Introduction Theories of Evolution Processes in Evolution

Outline How the concept of Evolution evolved? Processes in Evolution Needs of life – Mother of innovations and technology advancements

Evolution – An Introduction Process by which different kinds of living organism are believed to have developed from earlier forms during the history of the earth. Ref: http://www.iep.utm.edu/evolutio/

Theories Every organism type has been created at one time in multiple numbers and there is no change in the characters - GOD

LAMARCK’S THEORY Lamarck’s View Point Lamarck incorporated two ideas into his theory of evolution: Use and disuse – Individuals lose characteristics they do not require (or use) and develop characteristics that are useful. Inheritance of acquired traits – Individuals inherit the traits of their ancestors. Lamarck is best known for his Theory of Inheritance of Acquired Characteristics, first presented in 1801 (Darwin's first book dealing with natural selection was published in 1859): If an organism changes during life in order to adapt to its environment, those changes are passed on to its offspring. He said that change is made by what the organisms want or need. For example, Lamarck believed that elephants all used to have short trunks. When there was no food or water that they could reach with their short trunks, they stretched their trunks to reach the water and branches, and their offspring inherited long trunks. Lamarck also said that body parts that are not being used, such as the human appendix and little toes are gradually disappearing. Eventually, people will be born without these parts. Lamarck also believed that evolution happens according to a predetermined plan and that the results have already been decided.  

DRAWIN’s CONCEPT complex creatures evolve from more simplistic ancestors naturally over time: Concept of Natural Selection English Peppered Moth (Biston betularia) http://necsi.edu/projects/evolution/cover/evolution_cover.html

Processes in Evolution - Variation - Mutation - - Natural Selection - Adaptation

Need – Mother of Evolution

Next Class: Human Evolution