Biodiversity and Evolution

It is very difficult to measure insect and microbiological diversity accurately.

How is it possible that we don't currently know how many species are present on Earth?

Gene flow

Migration of organisms contributes to which of the following causes of evolution?

a threatened habitat that has high levels of species diversity and a large number of endemic species.

A biodiversity hotspot is?

Deoxyribonucleic acid

A gene is a sequence of compounds found within what kind of molecule?

A nucleus

A prokaryote cell lacks _____.

This particular group of mice appears to be genetically distinct (sub)species and therefore would qualify for protection under the ESA.

A small mouse population found in the Front Range of Colorado looks and acts very much like most other mice in the area; yet. this particular group of mice is thought by many to deserve protection under the U.S. Endangered Species Act (ESA). How could this be?

Vulnerable

A species classified as _____ by the IUCN is likely to become endangered unless threats to its existence are reduced.

The collection of animals for zoos

All of the following are major causes of biodiversity loss except?

About 25%

Based on the taxonomic groups shown here,approximately what percentage of the total threatened species in the United States and Canada are plants?

Genetic, species, and ecosystem

Biodiversity is a measure of the biodiversity of life at what levels?

Bacteria

Domain Eukarya includes all of the following except?

Mexico, Central America, and South America

Endemic species are species found only in one location. Regions with high numbers of endemic species are important for biodiversity conservation because you can maximize the number of species conserved. Based on the graph, which region has the largest total number of both total endemic species and threatened endemic species?

Eukaryotes

Evolutionary speaking, which of the following groups of organisms appeared most recently?

Traits, such as long necks, are developed over many generations through the process of natural selections; they are not the result of a lifetime of activity.

Explain what is wrong with the following statement: Giraffes have developed long necks over many generations because they keep stretching higher and higher to reach the highest leaves on trees.

Sedimentary

Fossils generally form in what kind of rock?

50 species

If there were 100 million species on Earth, how many species might we reasonably predict to become extinct annually assuming background extinction rates?

Kingdom

If two species are members of the same class, they would also have to be members of of the same _____?

A tropical rain forest

If you had $1 million and could buy 1 square kilometer of land somewhere in the world in order to preserve species diversity, which of the following locations would be the best investment?

Asia

If you were instead focused upon reducing total rates of extinction by the greatest amount (that is, extinction of not just endemic species, but of all species), which region would you focus your efforts in?

Mexico, Central America, and South America; and Asia

Imagine you re leading a global species conservation organization and want to figure out how to prioritize your conservation efforts. One option is to focus on the regions that have the largest number of threatened endemic species. Based on this priority, in which two regions would you focus your conservation efforts?

Conditions changed faster than the organisms were able to adapt to, and, as a result, these species eventually disappeared.

In past major extinction events, something happened (for example, climate change or meteorite impact), and then many species disappeared. What actually caused the species to disappear?

More diverse ecosystems have a broader mix of species, including some that are more likely to be able to tolerate changes such as drought, floods, or other extreme environmental events.

Many ecologists support the idea that more diverse ecosystems should be less affected by major environmental change than less diverse ecosystems. For example, a large drought would have a bigger negative impact on the life in a low-diversity ecosystem than it would on the life in a high-diversity ecosystem. Why would this be?

Genera

Mass extinction events are characterized by the disappearance of 20% of the _____ in the fossil record.

The current extinction rate is considerably higher (100 times or more) than the background rate.

The background extinction rate is about 1 extinction per 1 million species per year. How does the current rate of extinction compare to the background extinction rate?

5

The fossil record indicates the occurrence of how many mass extinction events?

Microorganisms

The species of what organisms are best characterized by genetic analysis?

Yes, because laws such as those in the U.S. Endangered Species Act focus on species-level conservation of threatened or endangered species.

There are many different definitions of a species. These include the capacity to interbreed, physical similarities, genetic similarities and others. Biologists spend a fairly large amount of time worrying about this definition, but does it make any difference for biodiversity conservation policy?

100 to 1,000

Today's global extinction rate is _____ times greater than Earth's background extinction rate.

They began to produce oxygen, which accumulated in the atmosphere.

What major impacts did photosynthetic bacteria have on Earth's atmosphere?

About 40-50%

What percentage of endemic species are also classified as threatened endemic species in Africa?

The characteristics of the rock in which the fossil was found.

What would you need to know to estimate when a fossilized fish lived?

Habitat loss

What's the primary (most important) cause of species extinction on Earth?

Areas near the Equator

Which areas of the World tend to have the greatest species richness?

The use of only a handful of species for the vast majority of our crops has made our food supply more vulnerable to pests and disease.

Which of the following about biodiversity is true?

Crop diversity has declined, as have populations of pollinators needed to pollinate our crops.

Which of the following accurately describes current trends in biodiversity and crop production

a random change in the genetic makeup of a population

Which of the following best describes genetic drift?

insects and their kin

Which of the following groups comprises the largest group of known species of the planet?

Plants

Which of the following groups of organisms has the greatest percent of species at risk of extinction today?

In a certain population of birds, the birds with larger beaks are better able to eat the hard seeds that are abundant in their environment. These birds survive and produce offspring with large beaks. Over time, the population has a larger proportion of birds with large beaks.

Which of the following is an example of evolutionary change?

Overexploitation

Which of the following is the major cause of biodiversity loss in Earth's oceans?

Habitat loss

Which of the following is the major cause of biodiversity loss on land?

Organisms that are similar in appearance generally have genomes that are more similar than organisms that look quite different.

Which of the following is true

Africa

Which of the following regions has the largest percentage of threatened endemic species?

Plants provide energy to ecosystems in the form of sugars.

Which of the following roles do plants play in an intact ecosystem?

Most genetic mutations have little to no effect on an organism.

Which of the following statements about mutations and natural selection is true?

Only traits that are a result of genetics can be passed down to the next generation

Which of the following statements accurately describes how traits are passed to future generations?

Traditional cost and benefit analyses of economic activity largely ignore the benefits of ecosystems and biodiversity, and therefore global ecosystems and biodiversity are in serious peril.

Which of the following statements regarding the benefits of biodiversity is true?

Asia

Which region has the largest total number of threatened species based on the taxonomic groups shown here?

Invertebrates and plants

Which taxonomic groups appear most often as having the most threatened species across all regions?

The genes of individuals within the same species can vary greatly, making some members of the same species more successful than others in certain situations

While most major U.S. conservation policy focuses on species diversity, scientists also look at other levels of diversity, such as genetic diversity. Why would genetic diversity be an important factor to consider when investigating the biodiversity of a group of organisms?

The temperature has been relatively stable over long periods of time in the tropics (where the Amazon rain forest is located) in comparison to other areas of the world.

Why does the Amazon rain forest generally have higher species diversity than temperate North American rain forests?

without mutations in genes, there would be no variation in traits that could be selected for.

Why is mutation an important aspect of how evolution occurs?

Speciation

______ is the process by which geographic isolation results in the formation of multiple species from a common ancestor.

Populations evolve, but individual members of the population do not.

which of the following statements about evolution is true?