Biology Segment 25.01 EvolutionIntroduction to Evolution:If a crime has been committed without any eyewitnesses, how can it be solved? Detectives look for a range of different types of evidence to help them solve the puzzle and determine what happened. This evidence can include: fingerprints, DNA, items out of place or left behind, clues that indicate a “timeline” of events, etc. In a similar way, scientists use fossils, DNA sequences, structural similarities, and other types of evidence to determine what happened in the past, how the organisms on Earth are related, and how there came to be such a variety of life on the planet today.Evolution: In biology, the term evolutionrefers to the processes that transform life on Earth from its earliest forms to the vast diversity on Earth today. These changes are based primarily on the interactions of organism populations and their environments. If evolution has been happening forbillions of years, how can scientists prove that it has occurred? Just as detectives can use evidence left at a crime scene to help determine the details of the crime, scientists use a variety of evidence left by living organisms to develop and support the theory of how life evolved on Earth. Many people hold very strong beliefs concerning the origin and evolution of life. The information in this lesson is presented from the perspective of the scientific community and should be approached with that in mind. In any case of differing belief systems, it is important that we know and understand what others believe. The current scientific views about evolution did not develop overnight. Like many other scientific theories, the theory of evolution is built on observations, scientific analysis, and evidence discovered by many different scientists working in several different fields. Before we discuss some of the scientists who have contributed to the theory of evolution, let’s introduce some of the terms that you will see.Botany/Botanist:Botany is a field of science that studies plants. Botanists are the scientists that work in this field of study.Anatomy/Anatomist:The field of anatomy is concerned with the bodily structures of humans, animals, and other organisms. Anatomists use dissection as just one of the ways in which they study body structures.Biogeography:The field of biogeography studies where on the planet species live now and wheretheir ancestors lived in the past.Astronomy/Astronomer: Astronomy is the field of science that studies outer space, including the position, distribution, dimensions, motion, composition, and energy of planets, stars, and other celestial bodies.Paleontology/Paleontologist: The field of paleontology is concerned with the study of fossilized plants and animals. Paleontologists are the scientists who work in this field.