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According to the fossil record, which statement is accurate?*
A photograph of a polar bear in its environment is shown below.
One possible reason why polar bears might not be able to survive if the environment they live in changes is because*
Base your answers to questions 3 on the information below and on your knowledge of biology.
The Galapagos pink land iguana, Conolophus marthae (C. marthae), is native to only one of the Galapagos Islands. Its entire range is currently limited to Wolf Volcano on Isabella Island. The iguana was first discovered on this island in 1986. Genetic studies of the animal began sometime later, and it was identified as a species separate from other iguana populations on the Galapagos in 2009. Its population might have been as high as 100 in 1986, but now there might be as few as 10 of the animals left alive.
Other evidence indicates that this species could have diverged from another line of iguanas about 5.7 million years ago. After that, the other line of iguanas diverged into two other species, C. pallidus and C. subcristatus.
In the future, the current population of about ten pink land iguanas will probably*
Ecologists are concerned that the golden-winged warbler population is at a dangerously low level. One reason this could lead to extinction of this warbler is that*
Examination of ancient rock layers at a certain location reveals many different fossils. Which conclusion can be drawn concerning the species that formed these fossils?*
The diagram below represents an evolutionary tree.
Which statement best describes species E?*
Extinction occurs when the environment changes and*
A scientist at a large natural history museum has a collection of fossils that were found throughout the world. Only a few of the fossils represent species that are still alive on Earth today. One reason for this is that*
Fossils provide evidence that*
As the rate of environmental change has increased over the last 50-100 years, there has been an increase in extinction rates. Lower reproductive rates seem to have also contributed to this increase in extinctions.
Describe one possible reason for an increased extinction rate in populations of species with a lower rate of reproduction. [1]*
Base your answers to questions 11 on the information and data table below and on your knowledge of biology.
Moose-killing Winter Ticks
Moose habitat is determined by temperature. Moose prefer areas where the average summer temperature is around 15°C and does not exceed 27°C for too long. The reason for this temperature dependency: Moose cannot sweat.
Besides the cooling effect of water, which moose are almost always near, aquatic environments provide them with a good supply of food, and in the past, have protected them against biting insects. However, the North American moose population is facing a new threat: a parasite called the winter tick. These ticks lodge themselves in the animal’s fur and hold on through the winter, sucking the animal’s blood. Many infected moose end up dying of exhaustion and weakness as a result of the large number of ticks feeding on them.
Ticks are most active during dry days in the fall. Adult ticks that drop off moose in the spring and land on snow cover have a poorer survival rate. Climate change can be predicted to improve conditions for winter ticks due to longer and warmer falls, and earlier snowmelt in the spring.
Surveys of the moose population in northeastern Minnesota have recorded the change shown below in the moose population between 2005 and 2013.
Directions: Using the information in the data table, construct a line graph on the grid below, following the directions below.
Explain how climate change could result in an increased number of moose infested with winter ticks. [1]*
Base your answers to questions 12 on the information and diagram below and on your knowledge of biology. The diagram represents the evolutionary relationships among many organisms.
An environmental change severely affected the organism represented by species K. What was the result?
Support your answer. [1]*
Base your answers to questions 13 on the diagram below and on your knowledge of biology. The diagram represents an evolutionary tree.
State one possible cause for the extinction of species E. [1]*
Explain why changes in climate can result in the extinction of a species. [1]*