Evolutionary Relationships — Unit test Answers

Consider the generalized cladogram of fish.Osteichthyes is a group of fish that have the derived characteristics of jaws and true bones. Which letter corresponds to where Osteichthyes belongs on the cladogram?

The fossil record shows that the average size of black bears was large during cold glacial periods and got smaller during warmer time periods. What is this an example of?

These notes were taken during a class about biological evolution, but the subject title is missing. -results from immigration -new genes brought into a population -variation in a population increasesWhat do the notes describe?

Read this passage about global fishing.Global consumption of large fish has led to an exploitation of fish populations. Overfishing has led to a decline in the populations of many species of large fish including North East Arctic Cod. The graph below shows the decline in the cod population.As the human population grows and countries continue to develop, the demand for large fish has been steadily increasing. Unfortunately, the average size of the cod has decreased because the fishing nets were designed to catch the large fish and the smaller individuals could escape more easily.What is most likely happening to the genetic variation of the population of North East Arctic Cod?

A student argues that two species of birds are the same species because they have similar body structures, similar DNA, and similar beaks. Another student argues that the birds are different species because they have different color patterns and have a different mating season. Which piece of evidence supports the second student's argument?

Consider the cladogram.According to the cladogram, which characteristic was used to separate bony fish from amphibians?

Consider the cladogram.Which is the best description of the two organisms highlighted in orange?

What is most likely to happen to a population of mice that becomes isolated on an island?

In rock layers, jellyfish fossils are found lower than trilobite fossils, and trilobite fossils are found lower than ammonite fossils. What can be determined from this information?

Read the following passage from the Biology Department at University of California, Berkeley.Northern elephant seals have reduced genetic variation because hunting by humans reduced their population size to as few as 20 individuals at the end of the 19th century. Their population has since rebounded to over 30,000, but their genes still carry the marks of this near extinction: they have much less genetic variation than a population of southern elephant seals that was not hunted as intensely.Which of the following best describes how the population has evolved?

A founding population of lizards arrives on an island. Which type of isolation would most likely result in this population becoming a new species?

Consider the group of giraffes in the image below.Which statement about the giraffes explains their evolution based on Charles Darwin’s main points?

Changes in the gene pool can occur due to various mechanisms. In 1989, a large oil spill occurred in Prince William Sound, Alaska, when the Exxon Valdez oil tanker ran aground. Approximately 11 million gallons of oil were spilled and spread 1,300 miles along the Alaskan coastline. The damage from the oil spill affected thousands of animals in the area, including killer whales, harbor seals, sea otters, fish, and sea birds. Which mechanism most likely affected the gene pools of the organism populations in the areas around the oil spill?

Darwin’s finches evolved on an island. What is the main reason that islands often provide good examples of evolution?

Which of these are most likely homologous structures? bat wing dragonfly wing Tyrannosaurus arm