Exam 25: The History of Life on Earth

What concept explains the evolution of complex eyes?

Use the following information to answer the question. A sediment core is removed from the floor of an inland sea. The sea has been in existence, off and on, throughout the entire time that terrestrial life has existed. Researchers wish to locate and study the terrestrial organisms fossilized in this core. The core is illustrated as a vertical column, with the top of the column representing the most recent strata and the bottom representing the time when land was first colonized by life. If arrows indicate locations in the column where fossils of a particular type (see key) first appear, then which core in the figure above has the most accurate arrangement of fossils?

You are the lucky student of a wacky professor who develops a time machine. He asks if you will test it with him. You get in, and there is an immediate glitch-the date readout fails so that when you land, you are not sure what era you are in. As your time machine lands, you see an unusual landscape before you. As you open the door, you realize you cannot breathe. You quickly shut the door, realizing you are in the ________.

Use the following information to answer the question. A sediment core is removed from the floor of an inland sea. The sea has been in existence, off and on, throughout the entire time that terrestrial life has existed. Researchers wish to locate and study the terrestrial organisms fossilized in this core. The core is illustrated as a vertical column, with the top of the column representing the most recent strata and the bottom representing the time when land was first colonized by life. To assign absolute dates to fossils in this sediment core, it would be most helpful if ________.

Endosymbiosis is an evolutionary theory that explains the origin of eukaryotes and suggests a specific order in which this might have occurred. Ancestral cells engulfed and then began to use the metabolic processes of the smaller cells. Based on shared-core processes and features, which statement most accurately describes the order, the theory, and the evolutionary implications for all organisms within domain Eukarya?

What major innovations of the three radiations was associated with defying gravity to facilitate life on land?

Upon being formed, oceanic islands, such as the Hawaiian Islands, should feature what characteristic, leading to which phenomenon?

Which factor most likely caused animals and plants in India to differ greatly from species in nearby southeast Asia?

Which of the following showed their greatest diversity during the Mesozoic era but were a small, less diverse group during the Paleozoic era?

Why are fossils considered to be an incomplete record of evolution?

The duplication of homeotic (Hox) genes has been significant in the evolution of animals because it ________.

A genetic change that caused a certain Hox gene to be expressed along the tip of a vertebrate limb bud instead of farther back helped make possible the evolution of the tetrapod limb. This type of change is illustrative of

Refer to the following information to answer the question. Fossils of Lystrosaurus, a dicynodont therapsid, are most common in parts of modern-day South America, South Africa, Madagascar, India, South Australia, and Antarctica. The animal apparently lived in arid regions and was mostly herbivorous. It originated during the mid-Permian period, survived the Permian extinction, and dwindled by the late Triassic, though there is evidence of a relict population in Australia during the Cretaceous period. Some dicynodonts had two large tusks, extending down from their upper jaws. The tusks were not used for food gathering, and in some species were limited to males. Food was gathered using an otherwise toothless beak. Judging from the fossil record in sedimentary rocks, these pig-sized organisms were the most common mammal-like reptiles of the Permian. What is thought to be the correct sequence of these events, from earliest to most recent, in the evolution of life on Earth? 1) origin of mitochondria 2) origin of multicellular eukaryotes 3) origin of chloroplasts 4) origin of cyanobacteria 5) origin of fungal-plant symbioses

If one organ is an exaptation of another organ, then these two organs ________.

A swim bladder is a gas-filled sac that helps fish maintain buoyancy. The evolution of the swim bladder from lungs of an ancestral fish is an example of ________.

Hawaii is the most southeastern of the seven largest islands and is also closest to the seafloor spreading center from which the Pacific plate originates, which lies about 5,600 km farther to the southeast. Assuming equal sedimentation rates, what should be the location of the thickest sediment layer and thus the area with the greatest diversity of fossils above the oceanic crust?

What adaptions by mammals helped their adaptive radiation after extinction of terrestrial dinosaurs?

The oxygen revolution changed Earth's environment dramatically. Which of the following took advantage of the presence of free oxygen in the oceans and atmosphere?

Adaptive radiations can be a direct consequence of three of the following four factors. Select the exception.