please answer all the questions answering only one question is not helpful. Use

Question

please answer all the questions answering only one question is not helpful.
Use the information in Figure 1 to answer Questions 1 through 3. (Click the image to enlarge figure.)

Figure 1? Geographic distribution of the two species, along with the pulse rate of individuals taken from various locations. Reproductive character displacement results from geographic overlap between two species of chorus frog. Pulse rate of the advertisement call of Pseudacris feriarum is displaced in areas in which P. nigrita is present (adapted from Fouquette 1975). Oscillograms (amplitude—x-axis, plotted against time—y-axis) are shown for calls of allopatric and sympatric P. feriarum, allopatric and sympatric P. nigrita, and a laboratory-raised hybrid. All calls were recorded at ?14°C and are plotted on the same time scale. Note the increased pulse rate and pulse number of the sympatric P. feriarum call relative to the allopatric P. feriarum call. Also note that the hybrid call is intermediate with respect to the two sympatric calls.

Question 1. Do populations of P. feriarum from Tennessee come into contact with the other species? Would you classify them as allopatric or sympatric populations?

Question 2. Do populations of P. feriarum from Florida come into contact with the other species? Would you classify them as allopatric or sympatric populations?

Question 3. Based on the pulse rate data, which species exhibits more reproductive character displacement? Explain.

Use the information in Figure 2 to answer Questions 4 through 9.

Figure 2? Variation in hybrid fitness across the life cycle. Examining both males and females, the researchers investigated the viability, mating success, and fertilization ability of hybrids, as compared with pure species P. feriarum. Bars above zero indicate that hybrids are favored relative to P. feriarum individuals, whereas bars below zero indicate that hybrids are disfavored. Strengths of selection on males, females, and combined individuals are shown (proportional to bar length). Single asterisk (*) denotes a P-value between 0.025 and 0.01, and two asterisks (**) denote a P-value less than 0.01. “Lifetime” highlights results for the overall strength of selection across the life cycle.

Question 4. Do hybrid males have significantly lower viability than pure P. feriarum males have?

Question 5. For which life cycle stage, and for which sex, do hybrids fare the worst?

Question 6. Are there any life cycle stages in which the hybrids do significantly better than the pure species?

Question 7. Overall, across all life cycles and both sexes, do hybrids have lower fitness than pure species individuals?

Question 8. How is Question 7 relevant to whether reinforcement is operating in this system?

Question 9. Suppose the researchers only examined the fitness of hybrid females. What conclusions would be different, and how would this affect whether they could claim that reinforcement is occurring?

Tennessee ·P. feriarum O Mixed O P. nigrita Florida 6 10 14 18 22 26 30 34 P nigrita Fl hybrid P feriarum Pulse rate (14'C) Geographic Overlap Reproductive Character Displacement Acoustic Signals

Explanation / Answer

Question1: The species P. feriarum is geographically isolated from P.nigrita, so that it will not contact with other species in tennessee. This kind of speciation which occurs due to geographical sepearion called as allopatric speciation. Allopatric specciation mainly driven by natural selection.

Question 2: The species P.feriarum doesn't exist in florida, but P.nigrita is only appear in florida, and there is no contact with the other species.

Question 3: The specices P. feriarum is showing more reproductive charecter displacement, as the advertisement calls in P.friarum are displaced in region where P.nigrita is present. This indicated the reproductive charecter displacement in P.feriarum. Reproductive charecter displacement is a mechanism by which the reproductive behaviour of species is changed in an overlapping regions to avoid hibridisation.

Question 4: No hibrid have viability more than 1 indicated that hibrid males are favoured and more viable.

Question 5: In male hibrids have lower fittness than pure individuals in mate choice as well as life span. In these two charecters of life cycles male hibrids are less favoured.

Question 6: The viability of the hybrids are better than pure species.

Question 7: Yes by considering all stages in life cycle hibrids shown lower fitness than pure hibrids.

Question 8: according to the present scenarion hibrids were showing overall lower fitness than pure individuals. Hence the species more likely to be reproductively isolated from the other. Hence we can say reinforcement is not succussfully operating.

Question 9: Hibrid females are better favoured than males in over all life cycle. so hibrid females being fit than the pure individuals the hibridisation in contact zone is possible, so reinforcement favours the hibridisation not the speciation.

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