Can anyone give a picture that shows the evolution of fish?

I need help with BIOLOGY muti choice, can anyone help?

• 25. To investigate selective pressures on fish populations, researchers set up three identical tanks, labeled X, Y, and Z. Each tank contained 1000 fish of the same species. Before the fish reproduced each generation, the researchers removed fish from some of the tanks. The graph below shows the changes in the mean weight of the fish in each tank over four generations. Based on the graph at the right, what did the researchers most likely do to tank Z each generation? A. The researchers removed the 900 smallest fish. B. The researchers removed the 900 largest fish. C. The researchers removed 900 fish at random. D. The researchers removed none of the fish. 26. Scientists have concluded that snakes evolved from an ancestor with legs. Which of the following statements provides the best evidence for this conclusion? A. Most species of snakes live on land. B. Snakes move extremely fast to catch their prey. C. Snakes have a well-developed backbone and muscular system. D. Some species of snakes have limb buds during their embryonic development. 27. Which of the following statements best explains why geographic isolation can lead to speciation? A. Physical separation of populations reduces competition for each group. B. Physical separation of populations prevents interbreeding and mixing of gene pools. C. Physical separation of populations provides more space for each group’s size to increase. D. Physical separation of populations stresses the organisms and causes mutations in their genetic code. 28. In a population of moths, wing color became darker over time. Which of the following is the best evidence that the change in wing color was an evolutionary change? A. The size of the moth population changed. B. The average length of the moths’ dark wings increased. C. The number of eggs that females laid during each breeding season increased. D. The frequencies of the alleles for dark wing color in the moth population changed. 29. Frogs, lizards, and birds all have a similar arrangement of bones in their limbs. Which of the following does this similarity most likely indicate about these animals? A. They move in the same way. B. Theey have a common ancestry. C. They evolved at the same time. D. They are comparable in size as adults. 30. Which of the following provides the most conclusive evidence that organisms of two different species share a common ancestor? A. They live in the same ecosystem. B. They reproduce at the same time. C. They have similar DNA sequences. D. They have similar body movements. 31. Dutch elm disease is a fungal infection of elm trees that usually results in death. The disease has killed millions of North American elm trees that were not resistant to the fungus. Scientists have bred resistant elms by crossing North American species with Asian species that show resistance. Which of the following best describes how natural selection would promote resistant elm populations once the resistance genes from the Asian species were successfully introduced? A. After encountering elms with resistance genes, fungi would avoid elms and begin to attack other tree species. B. Resistance would spread to all of the mature elms in a population from the few trees that acquired the resistance genes. C. By reproducing with each other, elm trees with resistance genes would create super-resistant elms with twice the number of resistance genes. D. Elm trees with resistance genes would survive and pass on resistance to offspring, while trees without resistance would more likely be killed by the fungus. 32. Which of the following best explains how the fossil record provides evidence that evolution has occurred? A. It indicates that forms of life existed on Earth at least 3.5 billion years ago. B. It indicates the exact cause of structural and behavioral adaptations of organisms. C. It shows how the embryos of many different vertebrate species are very similar. D. It shows that the form and structure of groups of organisms have changed over time. 33. The rock pipit and the water pipit are two types of birds found in the United Kingdom and other areas of Europe. The rock pipit and the water pipit have similar appearances and their habitat ranges overlap. Which of the following observations most likely caused scientists to classify the birds as separate species? A. The rock pipit is not able to produce fertile offspring with the water pipit. B. The rock pipit population in the United Kingdom is larger than the water pipit population. C. The rock pipit eats insects, fish, and seeds, but the water pipit eats only insects and larvae. D. The rock pipit remains in the United Kingdom year-round, but the water pipit only overwinters there

• Answer:

  25. Can't tell without a graph. If they increase in mass the smallest have been removed. If they decrease in mass the largest have been removed. If 900 are removed at random then mass will stay approximately the same. This is an example of artificial selection. 26. D I believe, as "ontogeny recapitulates phylogeny". 27. All are true, but B causes speciation. 28. D 29. B, but A could be true. Structures like eyes and wings have evolved independently several times over. 30. C. Members of the same species are genetically and biochemically similar. 31 D 32 D 33 A according to the biological definition of a species