PPT-Constraints on Natural Selection

Natural Selection does not always proceed in the expected direction because several forces could interfere with the action of Natural Selection Constraints on Natural Selection Genetic Variation. Evolution. Believed to be 4.5 billion years old. Thought to have had a very anaerobic atmosphere. Earliest organisms were able to survive primitive environments. Prokaryotes that resemble today’s bacteria. E.g., the evolution of pepper spiciness. …. What does natural selection “act on”?. the . gene. the . individual. the . population. or . group. the . species. They are in you and me; they created us, body and mind; and their preservation is the ultimate rationale for our existence. They have come a long way, those replicators. Now they go by the name of genes, and we are their survival machines.. Evolution: Teachable Tidbit. Context. : . Introductory biology for science majors . 2 full class periods and a follow-up exam question. Learning Goal. : We want students to understand that natural selection is a phenomenon that applies to their lives. Evolution- changes in the characteristics of groups of organisms over time . Charles Darwin was the first to propose a feasible . mechanism. for evolution. It is called . natural selection. . . Evolution by Natural Selection is a theory. . Relative fitness in relation to. Natural selection. Natural selection often has “survival of the fittest” and the “struggle to survive” associated with it, but it doesn’t necessarily mean direct physical conflict between two organisms.. Wednesday 1/22/14. Grab a book and a new . bellringer. so you are not TARDY. LT: I can identify types of selection. BR: What is natural selection?. ** if you finish . bellringer. begin & finish vocab for day 2. We will begin class 10 min after bell rings. Day 2 is due on Tuesday. What is natural selection?. It’s the . process whereby organisms better adapted to their environment tend to survive and produce more offspring. . The . theory. of its action was first fully . explained . Hasan. Mahmud. Natural Selection . Is the basis of the other types of selection. Competition Variation. Heriatble. Difference in survival. Relaxed and Artificial Selection are simply natural selection under different . Context. : . Introductory biology for science majors . 2 full class periods and a follow-up exam question. Learning Goal. : We want students to understand that natural selection is a phenomenon that applies to their lives. Motivation. Most powerful mode of evolution. Explains observation of Descent with Modification. Nonrandom survivorship/reproduction of individuals based on particular features of their phenotype. . Any environmental agent may be the cause of natural selection. Golden Girls Plus Alex Media Room B Group. Presentation Date: 140523. Presenters: Alex Bentley. . 288531. Nancy . Bocanegra. 320379. Cathy Odom 128180. . Evolutionary Ideas. A. lthough Darwin is given much credit for evolutionary theory, he was not the first person to come up with the idea.. Evolution is the change in a population over time.. The concept of evolution had been discussed for more than 100 years prior to Darwin’s theory.. A. Species overproduce offspring that may survive an environment.. B. There is little variation among members of a population.. C. Competition for resources, mates, and space among species leads to a struggle to survive.. Science. Learning intention. To know what 'natural selection' is and how it works. . You will need. A pen and paper or your laptop to record your answers. . The internet . to access the weblinks on later slides.