Transcript ppt
Darwin’s Theory of Evolution The History of Evolution • Evolution is defined as _________ over time • The theory that all organisms on Earth are related by __________ __________ and that they have changed over time (adapted) mostly because of __________ __________. • __________ __________ is one of the most famous scientists associated with the theory of evolution Darwin’s interest • Darwin’s observations and research played an important role in the development of the theory of evolution that is still __________ __________ today • During his voyage on the U.S.S. Beagle, he would collect specimens from the different areas he visited • He was fascinated to see the variety in the different plants and animals that he studied He did notice one similarity: All of the organisms he observed were well suited (well matched) to their _______________ Adaptation • An adaptation is any __________ ____________ that increases an organisms chance for __________ • Adaptations can be __________ or __________ and can be passed from generation to generation • The process of becoming __________ __________ to the environment Different types of adaptations: • Genetic adaptation – always genetically controlled (ex: 5 fingers, giraffe’s neck) Different types of adaptations: • Physiological adaptation – change in the reactions; can be genetic or not (ex: acclimation to altitude or climate, coat color change during seasons) Different types of adaptations: • Behavioral adaptation – change in behavior; can be genetic or not (ex: chimps using sticks to catch termites, bears eating garbage) Survival of the fittest • The ability of an individual to __________ and __________ is called __________ • Adaptations that help an animal become more fit to __________ and __________ more ____________ are commonly selected • This is known as __________ ___ ___ __________ Survival of the fittest is also known as __________ __________ Over time, natural selection will change the ____________ of a population, increasing the __________ of that population Proof? You want proof? • Evidence of evolution through adaptation and natural selection can be found in: – the __________ __________ – ____________ ____________ (different animals __________ similarly because of the same _______________ factors) – _______________ structures – Similarities in early development of ___________ TODAY… • Evolution is widely accepted by the scientific community • Theories are constantly changing based on new evidence (mitochondrial DNA, rapid evolution…) • Evolution is still occurring • Many species are becoming extinct because they cannot evolve as fast as humans are changing the environment. • Humans are “meddling” with evolution through artificial selection (fruit, dogs…)