Yesterday, 1-24-08, a guest speaker came to talk to my biology class about evolution. Her name was Ms. Mead and she works for an institution that promotes the teaching of evolution in schools. There are several definitions for the term evolution, there is "the gradual change in a species over time due to habitat and natural selection", but evolution is based on the thought that we all have a common ancestor that every living creature, and that after hundreds of thousands of years, each descendant having modifications, this one creature evolved into the many species we have today. There in much evidence for evolution, personally i cannot see how some people still disbelieve Darwin and the Theory of Evolution, it's like pretending the Holocaust didn't happen. The main evidences are:
*Biogeography- the distrebutions of organisms across the globe, current and past
*Comparative Anatomy- comparing the anatomy (bone structure mostly, but also, movement and muscle structure) of different creatures to see the similarities
*Molecular Biology-a branch of biology dealing with the ultimate physicochemical organization of
living matter and especially with the molecular basis of inheritance and protein synthesis
*Fossil Record- well fossils obviously
*Developmental Biology- which I believe is the study of how organisms develope.
The above five are the main evidences for biology. I am personally most interested in comparative anatomy and the fossil record. Useing comparative anatomy one can see that birds and bats didn't evolve one from the other, they're from completely different branches, birds evolved from reptiles and bats evolved from mice/rodent creatures. Ms. Mead talked about the discovery of the Burgess Shale in the Canadian Rockies, and the finding of Pikaia, the first known creature with an organ resembling a spinal cord. (pictured at the right)
There were many other organisms found at the Bugress Shale site, however the discoveries were put together incorrectly at times, because the paleontologists were trying to create creatures that they could recognise instead of trying to understand the way the organisms really were. I really and truely enjoyed her talk, or rather the things she talked about. I later talked to my mother, a biologist, and she showed me the many books she has on evolution and it's surrounding subjects, including the Cambrian Explosian and the Burgess Shale, such as Wonderful Life, Eight Little Piggies, Hens Teeth and Horses Toes, The Mismeasure of Man, The Pandas Thumb and Ever Since Darwin. I think I might do a little more reading on the subject.
