A population of chipmunks lives across the length of a valley in the mountains. One day a large section of the mountain breaks off, and the resulting rockslide divides the valley in half. Over time, the chipmunks on either side of the rockslide evolve and become different species. What type of speciation is this?

In the following scenario, what mechanism(s) of evolution appear to be in play? Also from what lake do you think this population may be most closely related to? What may explain how the population in A came to be here? On the Paruna River, Southern Brazil This oxbow lake (a lake formed when a section of a river is cut off) floods when the winter rains occur (call in lake A). At those times animals from the lake and river can mix. Currently it is the dry season (low water levels in the river) and no flooding has occurred for the past five years. In this lake there is a population of leaf-mimic fish. These fish spend most of the day floating on their sides, acting like dead leaves. At this time they show mainly the brown color morph (some fish are yellow, orange, red, likely to match the species of tree that surrounds the body of water). At this time the lake is surrounded by a tree that drops leaves which are brown in color. Color pattern in this fish is genetic. A few miles downriver…

Distinguish between anagenesis and cladogenesis. Which mechanism of speciation is more prevalent? Why?

Imagine there's a species of flower that blooms in early April. Some seeds are blown over a mountain and the offspring of those seeds start a new population on the other side. After several million years the mountain erodes and the two flower populations are reintroduced to each other. The population that lived on the far side of the mountain flowers in early May, while the other still flowers in early April. The two populations never hybridize, and become their own species. This is an example of: Gametic Barrier Temporal Isolation O Habitat Isolation O Behavioral Isolation 1.