Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
EVIDENCE OF EVOLUTION Key Concepts • What evidence supports the theory of evolution? • How do scientists infer evolutionary relationships among organisms? • How do new species form? Key Terms Homologous Structures –Body parts that are ____________________ similar in related species. Branching tree –A _____________ that shows how scientists think different groups of ________________ are related. Identifying Supporting Evidence • Identifying supporting evidence helps us understand the relationship between the facts and the __________________. • _________________ consists of facts that can be confirmed by testing or observation. Supporting Darwin’s Theory • Fossils show that organisms that lived in the __________ were very different from organisms alive today. • Patterns of early ____________________ show that some different organisms look similar during their early stages. • Similar body structures in different species show that the organisms shared a ___________________ ancestor. Interpreting the Evidence • ____________________ • _____________________________ • ______________________________ FOSSILS • The _______________________ remains or traces of an organism that lived in the past. • Fossils show that organisms that lived in the past were very different than organisms alive today. • Scientists use _____________________ to infer the structures of ancient organisms. EARLY DEVELOPMENT (embryology) • Scientists compare the early development of different organisms to make ____________________ about evolutionary relationships. • Similarities in early development among different organisms suggests that they are related and share a _________________________ ancestor. BODY STRUCTURE (homologous structures) • Darwin compared body structures of ___________________ species when observing the species on the Galapagos Islands. • Body structure is an organism’s body plan, how its bones are ______________________. • Similarities in body ___________________ provide evidence that organisms evolved from a common ancestor. Species Relationships • Fossils, early development patterns, and body structure provide _________________ that evolution has occurred. • Scientists also have used these kinds of evidence to _________________ how organisms are related to one another. New Evidence •___________________ •___________________________ Similarities in DNA • Scientists compare the genes of different _________________ to determine how closely related the species are. • The more similar the sequence of bases in the ___________, the more closely related the species are. • The more similar the order of _______________________ (codes for proteins) in the DNA, the more closely related the species are. Combining Evidence • The use of DNA and __________________ structure has confirmed conclusions that scientists had already based on fossils, embryos, and body structure. • The use of DNA and protein structure has also caused scientists to “_______________” the branching trees of some species. Branching Trees •_____________________ show common ancestry, which is known as ________________. • Evolution is about ____________________ and phylogeny. How Do New Species Form? (speciation) • A new species can form when a group of individuals remains _________________ from the rest of its species long enough to evolve different traits. • Isolation/Separation –____________ –__________________ –_____________________ Convergent Evolution • The process whereby organisms not closely related, independently ______________ similar traits as a result of having to adapt to similar environments or ecological niches. Divergent Evolution (adaptive radiation) • The process by which related species evolve different ________________. Gradualism ________________occurs slowly but _______________.