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Mark for review whats this question 2 of 4 40 points

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Mark for Review What's This? Question 2 of 4 4.0 Points Let’s take a journey to Lake Stanford. Long ago, there was only one species of cichlid fish inhabiting the lake. Over time, though, you notice that five different cichlid species have evolved from it, each with its own peculiar fin structure corresponding to particular niches in the environment. Stanford soon builds a dam across the lake, though, to generate electricity for FroSoCo. This divides the lake into two unequal portions, and the fish cannot cross from one portion to the other. After some time, you notice that although the five species in the smaller portion of the lake don’t appear to change, the fish in the larger portion are beginning to look different, developing new fin shapes, etc., even though the selective pressures remain the same for both portions of the lake. These fish are no longer able to mate with fish from the first portion of the lake, even when artificially introduced to each other. Soon after this dam is built, a new predator - Cal bearii - is introduced to the area. You notice, though, that a new fish morph (form), with a pectoral fin as the shape of a tree, has arisen in both portions of the lake. You investigate and discover that this fin shape confers upon it better fitness to avoid Cal bearii , which is really scared of tree shapes. Given this scenario (and this is the only information you know about these fish), choose all the terms that can definitively be said to be in play for the evolution of cichlid fish in this situation. A. Allopatric speciation B. Sympatric speciation C. Directional selection D. Dobzhanksy-Muller incompatibilities E. Genetic drift F. Habitat isolation G. Behavioral isolation H. Temporal isolation I. Mechanical isolation J. Gametic isolation K. Reduced hybrid viability L. Reduced hybrid fertility M. Hybrid breakdown N. Parallel evolution Mark for Review What's This? Question 3 of 4 4.0 Points Insects are incredibly diverse and we have many examples of reproductive barriers. Below, match the example to the type of prezygotic barrier that it represents:
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4/12/13 6:34 PM 2013 Problem Set 2 on Evolution Lectures 4-6 Page 8 of 10 https://coursework.stanford.edu/portal/tool/1c2f43e9-1653-4e97-98f7-93a4fbb2cb09/jsf/delivery/beginTakingAssessment A. behavioral isolation B. gametic isolation C. temporal isolation D. mechanical isolation select 1. In the firefly genus Photinus, females recognize conspecifics (individuals of the same species) based on the timing and duration of the flashes of light produced by males. select 2. In many insects, females mate multiple times and their subsequent eggs can be fertilized by sperm from the first, last, or multiple males. In the case of multiple males contributing to the fertilized eggs, there may be competition between sperm in order to fertilize a higher proportion of eggs. In the bruchid beetle, Callosobruchus maculatus, it has been shown that when females are mated with males from both their own population and a geographically isolated population, more eggs are fertilized by sperm from males from the same population as the female.
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Mark for Review Whats This Question 2 of 4 40 Points Lets...

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