During the class, we examined the evolution of frog species. After the construction of a highway, at year 5000 (L12&13 Species Concepts and Speciation in class, Slide 34), the population at the right side of the highway and the population at the left side of the highway evolved into two new species. What mode of speciation-- allopatric or sympatric--led to these two frog species? Provide your reasoning making reference to the information that you know about these organisms.

In which of the situations below would speciation be most likely to occur? You can choose more than one answer. a. Seven lemurs escape from an enclosure at Duke University. To everyone's surprise, they establish a small but viable population coexisting successfully with humans in a partly suburban environment very different from their native Madagascan habitat. b. Bighorn sheep occupy mountains from Canada to Death Valley in Southern California, interbreeding all along the way. The populations at the two ends of the range live in very different environments. c. A few individuals of a butterfly species were blown to an island during a severe storm. d. A population of juniper shrubs is split by the formation of a canyon. Every year, strong winds carry a small amount of the shrubs' pollen across the canyon.

Topic: Galapagos Finches Darwin’s readings took him to a predictive theory of how species might change with time: what later thinkers have called microevolution. Darwin’s philosophical worldview then took him beyond his evidence to a conviction that environmental constraints could create whole new structures and organisms. Soon Darwin’s theory of macroevolution replaced the Creator with an environment that could create solely by constraint. For your thread: According to Chapter 13 section 13.1, define microevolution and macroevolution. The Galapagos islands have a great diversity of landscapes – from lush vegetation to nearly barren lava fields yet the Galapagos Finches survive on each island. How can this be explained? Using the varying bills of the Galapagos Finches in figure 13.3 and additional research, explain how microevolution is evidenced.