Concept explainers
To determine: The percentage of warfarin-resistant rats in town Olf.
Introduction: Rodenticides are the pesticides that have a capability to kill the whole rodent species. Rodents have their own importance in the nature but sometimes require some control over their population, as they could transmit disease, destroy crops, and may cause ecological damage. Warfarin is a common anticoagulant that could be used as a rodenticide to kill mice and rats.
After the discovery, warfarin has been widely used and later it resulted in development of species of warfarin-resistant mice and rats. Another recently developed bromadiolone called as super-warfarin (second-generation warfarin) has a greater ability to accumulate in the liver and kill the organism.
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Biology: The Unity and Diversity of Life
- Imagine three islands, each with a population of frogs. There are approximately 1,100 frogs on Island 1, 400 on Island 2, and 400 on Island 3. Researchers estimate that these populations have been separated for 800 years. Individuals in these populations show variation in markings on their body by shape and color. Frogs on Islands 1 and 2 have circle markings that are either red, blue, or purple. All frogs on Island 3 have yellow triangle markings. The islands recently became a tourist destination, with new passenger boats connecting Island 1 and Island 2, and Island 1 and Island 3 (there is no boat that goes between Island 2 and Island 3). part 1:If frogs from Island 1 migrate to Island 3 but are unable to reproduce with the frogs on Island 3, then these populations would be classified as different species according to the Biological Species concept. agree or disagree part2: If frogs are able to sneak onto boats and move between the islands via the current routes, then gene flow…arrow_forwardOn the right is a figure showing the reconstructed route of colonization of a rodent species found on the continent and four offshore islands, A, B, C, and D. Since the ocean currents around these islands are extremely strong, you suspect that these colonization events are rare, likely have happened only once. To estimate the overall genetic diversity of each population, you surveyed alleles frequencies of several neutral loci. Which of the following statements is correct? The genetic diversity would be the highest on island D because all migrations ended up on the island. If the level of genetic diversity is plotted against the distance from continent, we would expect to observe a steady increase of genetic diversity as the distance becoming farther away from the continent. The genetic diversity on island A would be lower than that of the continent because there is selection on the island removing deleterious alleles. This is an example of…arrow_forwardIt is well known among population geneticists that a population bottleneck in the past history of a species be observed in a low effective population size for many future generations. It is known that the human population size crashed to about 10,000 individuals at about 70-100,000 years ago. Do the effective population sizes of the chimpanzee and the gorilla suggest that this event (ash from an eruption in Indonesia) did not cause as significant a bottleneck effect in these primates as it did in humans? Give a reason for your answer.arrow_forward
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