SC.912.L. 15.5 EVOLUTION SC.912.L.15.8 Origin of Life BENCHMARK REVIEW SC.912.L. 15.5 EVOLUTION SC.912.L.15.8 Origin of Life

Bell Ringer:03.25.13 Scientists are studying the evolutionary history of a group of plants in the United States, and they developed an evolutionary tree, as shown below. Which statement can be inferred from the evolutionary tree? Species 1 is most closely related to Species 8. Species 2 is most closely related to Species 3. Species 3 is most closely related to Species 7. Species 5 is most closely related to Species 6.

What You Need To Know You need to know how the theory of evolution is supported by evidence from the fossil record, comparative anatomy, comparative embryology, biogeography, molecular biology, and observed evolutionary change. You need to know trends in hominid evolution from early ancestors to modern humans including brain size, jaw size, language and manufacture of tools. This benchmark will be assessed together with nature of science benchmarks. You will need to draw scientific conclusions based on the evidence or scenario given. You need to know the differences between a theory and a law and know how a theory is developed over time.  You need to know how specific scientists (Darwin, Lyell, Malthus, Mendel, Wallace) contributed to the theory of evolution.

Getting the Idea Our planet is about 4.6 billion years old. Since its fiery beginning, Earth’s temperature, climate, physical features have changed. The biological term for the process by which species of organisms change over time is evolution. There is much scientific evidence to show that Earth’s organisms have evolved.

Comparative Anatomy and Embryology Evidence of Evolution Biogeography Comparative Anatomy and Embryology Fossil Evidence Chemical evidence

Homologous Structures Body parts of different organisms that have a similar structures but not necessarily a similar function.

Analogous Structures Body parts that have a similar function but not similar in structure

Vestigial Structures Body parts that do not seem to play a role in the body functions of the organisms.

Observed Evolutionary Change

Gradualism Gradualism involves a slow, steady change in a particular line of descent. The fossil record shows that many organisms have indeed changed gradually over time.

Punctuated Equilibrium Punctuated equilibrium is the term used to describe equilibrium that is interrupted by brief periods of more rapid change. The fossil record reveals periods of relatively rapid change in many groups of organisms. Some biologists suggest that most new species are produced during periods of rapid change.

Hominid Evolution You have read that the species that inhabit earth have evolved over time. Like other species, humans have also changed since the first appearing on earth. Most of the evidence for how humans have changed is provided by fossils.

Skulls of Hominids

Trends in Hominid Evolution Bipedalism Increase in cranial capacity, brain size Changes in skull shape, decrease in the size of brow ridge Decrease in jaw size, angle at which the jaw protrudes from the face Decrease in the size of teeth Development of the ability to make and use tools Development of the ability to communicate using language

Individual Review