When Darwin returned from his journey he began compiling all of his thoughts and findings together. He also took theories into account from former scientists. Scientists that helped lead to Darwin's theory of natural selection mainly include his own grandfather Erasmus Darwin, Georges Buffon, and Charles de Lamarck. Each of the theorist had an influence on Darwin's theories and contributed in their own way.
(A great activity for students to participate in is to research each of the theorist who contributed to Natural Selection and creat a timeline. An example of the timeline is posted in the activities page)
Charles de Lamarck, played the biggest role in influencing Darwin's theory of natural selection and was actually very close to the theory itself.
Lamarck was the first scientist to realize that the environment played a large role in the evolution of species. He contributed to the theory by discovering aquired traits in species that arose from environmental influence. He proposed the thought that species became more evolved and complex over time in order to survive in their changing environment. Lamarck used the giraffe for an example. He had determined that throughout many, many years the giraffe had evolved from a smaller, horse-like animal into the giraffe we know and see today. The long neck of the giraffe was an aquired trait that the giraffe needed in order to survive as bushes and trees began to grow taller . The one factor that Lamarck was missing was not that animals evolved or time but how. Lamarck beleived that the giraffes simply passed thes aquired traits on to their young by physically stretching their necks through time. What he didnt realize was these adaptations could only be passed on through a gentic mutation. The difference was that these traits and adaptations were inherited traits and not simply aquired.
Darwin also began to critically study the process of artificial selection. He began breeding his own pigeons and experimenting in his gardens with plants as well. At this time, humans had been improving the quality of their crops through artificial selection for years. The process of choosing plants with the desired traits needed to breed allowed their crops to be more successful. If farmers could do this with their crops then why couldnt the environment be a factor on selection of species traits as well ? An example of artificial selection is the production of corn oil. By breeding the generations of crops that produce the most oil with other crops that produce the most oil, farmers were able to weed out the undesirable traits and grow plants that produced over 10% more oil.
The video below is a great example of artificial selection as it leads to Natural Selection. If you can not play the full video start it at the 4.45 mark.
(A great activity for students to participate in is to research each of the theorist who contributed to Natural Selection and creat a timeline. An example of the timeline is posted in the activities page)
Charles de Lamarck, played the biggest role in influencing Darwin's theory of natural selection and was actually very close to the theory itself.
Lamarck was the first scientist to realize that the environment played a large role in the evolution of species. He contributed to the theory by discovering aquired traits in species that arose from environmental influence. He proposed the thought that species became more evolved and complex over time in order to survive in their changing environment. Lamarck used the giraffe for an example. He had determined that throughout many, many years the giraffe had evolved from a smaller, horse-like animal into the giraffe we know and see today. The long neck of the giraffe was an aquired trait that the giraffe needed in order to survive as bushes and trees began to grow taller . The one factor that Lamarck was missing was not that animals evolved or time but how. Lamarck beleived that the giraffes simply passed thes aquired traits on to their young by physically stretching their necks through time. What he didnt realize was these adaptations could only be passed on through a gentic mutation. The difference was that these traits and adaptations were inherited traits and not simply aquired.
Darwin also began to critically study the process of artificial selection. He began breeding his own pigeons and experimenting in his gardens with plants as well. At this time, humans had been improving the quality of their crops through artificial selection for years. The process of choosing plants with the desired traits needed to breed allowed their crops to be more successful. If farmers could do this with their crops then why couldnt the environment be a factor on selection of species traits as well ? An example of artificial selection is the production of corn oil. By breeding the generations of crops that produce the most oil with other crops that produce the most oil, farmers were able to weed out the undesirable traits and grow plants that produced over 10% more oil.
The video below is a great example of artificial selection as it leads to Natural Selection. If you can not play the full video start it at the 4.45 mark.
For a good summary chart of Natural Selection click the button below. This chart could be used as a study guide for students or as a graphic organized from a lesson.