Developing a Theory of Evolution
Evolution processes earliest forms diverse The processes that have changed life on earth from it’s earliest forms to the diverse forms found today. changegenes!!!!!! A change in the genes!!!!!!
What Influenced Darwin’s Theory? Jean Baptiste Lamarck Jean Baptiste Lamarck ( ) 1 st to recognize living things change over time made 3 incorrect assumptions: 1) DESIRE TO CHANGE 2) “Use it or Lose it” 3) Aquired traits can be inherited
Charles Lyell ( ) A geographer- A geographer- studied the forces that change the surface of the Earth Wrote famous book “Principles of Geology” Showed that the Earth was VERY old and had changed over time Darwin Convinced Darwin Earth was older than most believed gave the time needed for Darwin’s Theory of evolution to occur
The Influence of Farmers & Artificial Selection Darwin spoke to lots of plant and animal breeders, noticed variation occurred naturally Farmers choose to only breed animals /crops with DESIRABLE VARIATIONS Therefore, farmers were artificially selecting (mates/traits) so that only the best traits were passed on via reproduction
Thomas Malthus ( ) Observed more babies being born than people dying… population should be growing out of control Many species make lots of eggs/sperm BUT ONLY A FEW OFFSPRING survive! Ex) Salmon for 4000 eggs 1survives ]Ex) Humans 150,000 sperm only 1 fertilizes egg
Charles Darwin ( )
Darwin H.M.S. Beagle Set sail on the H.M.S. Beagle for 5 years! ( ) Surveyed the South seas Was most influenced by South America and ESPECIALLY the Galapagos Islands! Collected plants and animals & wrote detailed observations In 1859 Wrote “Origin of Species” to explain his Theory of Evolution…
Darwin’s Theory of Evolution 4 main points: 1.Over population/reproduction not all offspring actually survive not all offspring actually survive 2.Variation Exists WITHIN species Not all offspring are exactly the same 3. Less “Fit” organisms die 3. Less “Fit” organisms die 4. More “Fit” organisms survive 4. More “Fit” organisms survive