A species is a group of individual organisms that interbreed and produce fertile, viable offspring. According to this definition, one species is distinguished from another when, in nature, it is not possible for matings between individuals from each species to produce fertile offspring. Evolution is an important mechanism in the formation of new species. The evolution of a new species requires several components including all, BUT   A) Evolution of a new species requires a long time.     B) Evolution of a new species requires the need for a genetic change.     C) Evolution of a new species requires a separation that prevents interbreeding.     D) Evolution of a new species requires mutations that produce new genetic traits. not graded use photo

You conduct an exercise in the Darwinian Snails Sim-U-Text lab. You simulate conditions under which survival of snails is selective-that is, snails with thicker shells are less likely to be preyed on by crabs than snails with thinner shells. The default settings also ensure the trait is heritable, and the population has variation in this trait. You allow mutations to occur. As you run the simulation, you observe that the mean shell thickness of the population increases over successive snail generations. Have you successfully simulated natural selection? No, because no snails appeared with thicker shells than the thickest shells observed in the initial population O Yes, because crabs preyed on the snails O No, because you cannot have selection with mutations operating No, because the changes in shell thickness could have been due to genetic drift O Yes, because there was a change in the mean shell thickness Yes, because there were mutations

A population of 600 scorpions was split into four populations when irrigation canals were built through their habitat. The four new populations were called the Northern, Southern, Eastern, and Western populations. Each new population consisted of about 150 individuals. The four populations continued to evolve, and no migration occurred among populations. One hundred generations later, each population still has about 150 individuals, and a biologist investigates them.  Consider what a biologist expect to see in the four populations after 100 generations if the environment did not change for any of the populations. Would the biologist agree or disagree with the following statements?  a) In the smaller populations of 150 individuals, the processes leading to genetic drift could have a stronger influence on a gene than natural selection. agree or disagree b)Chance survival of some individuals occurred in some generations, but not every generation. agree or disagee c)Beneficial mutations…

Which of the following is not true for natural selection to occur? a) there should be variation within the population b) individuals with some genotypes have more offspring than individuals with others c) more individuals are born than can survive d) only individuals with favored alleles survive e) variation between individuals should be explained by genetics rather than environment

Lamarck was an early naturalist who published his own ideas about species changing over time. He, however was mistaken about one critical aspect of evolution. If you could travel back in time what advice would you give Lamarck to correct his misunderstanding? Tell him that species actually do change and evolve over time Tell him that traits acquired during an organisms life are not passed on to offspring Tell him that artificial selection does not lead to new varieties of plants and animals Tell him that characteristics are heritable: Parents do pass on their characteristics to their offspring

One possible definition of evolution is that evolution can be seen as the change of allele frequencies with time. 1)True 2) False

A population of lizards in Northern California is brown and is not poisonous to birds. A population of lizards in Southern California is orange and is poisonous to birds. In central California, where the two species overlap, a new species of non-poisonous, orange lizards arose. Which of the following statements best explains the existence of non-poisonous orange lizards? A) Non-poisonous brown lizards changed color once they noticed birds did not eat orange lizards. B) Non-poisonous orange lizards have a selective advantage since birds avoid orange lizards. C) Non-poisonous lizards turn orange by eating orange flowers and then pass the trait on D) Non-poisonous orange lizards have a selective disadvantage since they cannot blend in. E) Non-poisonous brown lizards are more attractive to mates.

For natural selection to occur, there must be competition for resources, competition for survival, or 15) different reproductive success. Why is this so? A) Without competition, there is no pressure to mutate.B) The struggle of competition makes individuals stronger.C) Natural selection acts on the different abilities of individuals to survive and pass on their genes to the next generation.D) Populations evolve to preserve the species and don't change unless they must. Then explain why the answer is correct and why the others one are inccorect.

Which of the following is likely a reason why evolutionary radiation would occur on islands? A) there are many more species on islands B) islands tend to have more favourable habitats than continents because they are moderated by the ocean C) islands may have fewer animal and plant groups and thus provide more ecological opportunities D) organisms can disperse easily across oceans E) islands often have more diverse habitats than continents

When the isthmus of Panama (land bridge that connects north and south America) arose about 3 million years ago, it caused species of fish to diverge into sister species located in either the caribean or pacific ocean. Why did they form separate species?   A) Because this is an example of sympatric speciation   B) Because the tides are different on each side of the land bridge   C) Because different predators in each ocean caused the populations to diverge   D) Because the populations were reproductively isolated