* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Evidence of Evolution
Survey
Document related concepts
Unilineal evolution wikipedia , lookup
Hologenome theory of evolution wikipedia , lookup
Molecular paleontology wikipedia , lookup
The Descent of Man, and Selection in Relation to Sex wikipedia , lookup
Hindu views on evolution wikipedia , lookup
Genetics and the Origin of Species wikipedia , lookup
Catholic Church and evolution wikipedia , lookup
Evolving digital ecological networks wikipedia , lookup
The eclipse of Darwinism wikipedia , lookup
Theistic evolution wikipedia , lookup
Precambrian body plans wikipedia , lookup
Evidence of common descent wikipedia , lookup
Vestigiality wikipedia , lookup
Koinophilia wikipedia , lookup
Transcript
Evidence of Evolution Evidence of Evolution ⦿ Homologous Structures: › Similar features that originate from a shared ancestor › look different and have different functions › skeletal structures (bones) very similar and are derived from same embryological structures ⚫ Ex: Forelimbs of animals Evidence of Evolution ⦿ Analogous Structures: › Structures that have similar function, but are genetically different (different internal structures) › Do NOT have a close common ancestor › Adaptations that have evolved to fit similar environments ⚫ Ex: Insect wings and bird wings Evidence of Evolution Continued…. ⦿ Vestigial Structures: › Features that exist, but are no longer used › Feature that was useful to an ancestor, but is no longer useful to the modern organism › Ex: ⚫ Human appendix ⚫ Whale and snake leg bones Evidence of Evolution ⦿ DNA/RNA (Macromolecules) : › Compare organisms on a molecular level by using DNA & RNA ⚫ Determining Relatedness ⚫ Compare the strands of DNA from 2 or more different organisms. ⚫ The more base pairs that “match” the more related you are ⚫ Differences in DNA sequences are caused by genetic mutations ⚫ Mutations that cause beneficial traits are passed onto offspring Example: 1. Which organism is more related to a human and why? 2. What evidence do you have to support your answer? Evidence of Evolution ⦿ Fossils: › Comparing present day organisms to extinct organisms looking for similarities. › Relative Dating: ⚫ Using rock layers to determine the approximate age of fossils. ⚫ Oldest layers are on the bottom, newer fossils on the top Evidence of Evolution Evidence of Evolution Continued…. ⦿ Embryology: › Embryological development repeats throughout evolutionary history › Earliest stage of growth and development ⚫Occurs while still in the egg or womb Evidence of Evolution ⦿ Embryology: › Similar genes drive the development of similar traits during different developmental stages. (In the animals below, the same gene gets turned on in early development to create a tail.) › Development of adult characteristics usually happens in the late stages of embryology. (In the animals below, the human tail has receded in stage III. › Embryology Review of Darwin’s Theory of Evolution All species descended from one or a few original types of life. 2. Environment puts pressures on organisms which limits population growth. 1. › Natural Selection: ⚫ Organisms best adapted to their environment tend to survive and transmit their genetic characteristics more so than those less adapted. › Survival of the “fittest”. Darwin’s Evidence What types of evidence did Darwin use to support his theory? › Today’s species are related to extinct species ⚫ Fossils show changes in species over time ⚫ Use of fossils and Relative Dating › Related species have unique adaptations ⚫ Compared the internal and external structures of living organisms to the structures of fossils. ⚫ Darwin’s finches have beaks adapted for specific environments and specific tasks. Darwin’s Finches Evidence 2.0 What types of evidence do we use today to support Darwin’s theory? 1. Use of fossils and Relative dating and Radioactive Dating 2. Compared the internal and external structures of living organisms to the structures of fossils ⚫ Vestigial Structures ⚫ Homologous Structures 3. Embryology ⚫ comparing early developmental stages of organisms 4. DNA ⚫ comparing the DNA base pair sequences of organisms.