Evolution, the Themes of Biology, and Scientific Inquiry

First, make sure you understand how the graphs are set up. Graph A shows data from the light-colored soil enclosure and graph B from the dark-colored enclosure, but in all other respects, the graphs are the same. (a) There is more than one independent variable in these graphs. What are the independent variables, the variables that were tested by the researcher? (b) What is the dependent variable, the response to the variables being tested? Which axis of the graphs has the dependent variable?

How does science differ from technology? 

All the organisms on your campus make up

a. an ecosystem

b. a community

c. population

d. a taxonomic domain

(a) How many dark brown mice were caught in the light-colored soil enclosure on a moonlit light? (b) How many dark brown mice were caught in the dark-colored soil enclosure on a moonlit night? (c) On a moonlit night, would a dark brown mouse be more likely to escape predation by owls on dark or light-colored soil? Explain your answer.

The gene that causes sickle cell disease is present in a higher percentage of residents of Sub-Saharan Africa than among those of African descent living in the United States. Even though this gene causes sickle cell disease, it protects from malaria, a severe illness widespread in Sub-Saharan Africa but absent in the United States. Discuss an evolutionary process that could account for the different percentages of the sickle cell gene among residents of the two regions.

System biology is mainly an attempt to

a. analyze genomes from different species.

b. simplify complex problems by reducing the system into smaller, less complex units. 

c. understand the behavior of entire biological systems by studying interactions among its components.

d. build high-throughput machines for the rapid acquisition of biological data.

(a) Is a dark brown mouse on dark-colored soil more likely to escape predation under a full moon or with no moon? (b) What about a light brown on light-colored soil? Explain.

(a) Under which conditions would a dark brown mouse be most likely to escape predation at night? (b) A light brown mouse?

A controlled experiment is the one that 

a. proceeds slowly enough that a scientist can make careful records of the results. 

b. tests experimental and control groups in parallel.

c. is repeated many times to make sure the results are accurate. 

d. keeps all the variables constant.

(a) What combination of independent variables led to the highest predation level in enclosures with light-colored soil? (b) What combination of independent variables led to the highest predation level in enclosures with dark-colored soil?

Thinking about your answers to question 5, provide a simple statement describing conditions that are especially deadly for either color of the mouse.

Which of the following is an example of qualitative data?

(A) The fish swam in a zigzag motion.

(B) The contents of the stomach are mixed every 20 seconds.

(C) The temperature decreased from 20ºC to 15°C.

(D) The six pairs of robins hatched an average of three chicks each.

Which sentence best describes the logic of scientific inquiry?

(A) If I generate a testable hypothesis, tests and observations will support it.

(B) If my prediction is correct, it will lead to a testable hypothesis.

(C) If my observations are accurate, they will support my hypothesis.

(D) If my hypothesis is correct, I can expect certain tests results.

A typical prokaryotic cell has about 3,000 genes in its DNA, while a human cell has almost 21,000 genes. About 1,000 of these genes are present in both types of cells. Based on your understanding of evolution, explain how such different organisms could have this same subset of 1,000 genes. What sorts of functions might these shared genes have?

Based on the results of the mouse coloration study, suggest another hypothesis researchers might use to study further the role of predators in the natural selection process.

Scientists search the scientific literature using electronic databases such as PubMed, a free online database maintained by the National Center for Biotechnology Information. Use PubMed to find the abstract of a scientific article that Hopi Hoekstra published in 2015 or later.

In a short essay (100-150 words), discuss Darwins’s view of how natural selection resulted in both unity and diversity of life on Earth. Include in your discussion some of his evidence. (See a suggested grading rubric and tips for writing good essays in the Study Area of Mastering Biology under “Write About a Theme.”)

Can you pick out the mossy leaf-tailed gecko lying against the tree trunk in this photo? How is the appearance of the gecko a benefit in terms of survival? Given what you learned about evolution, natural selection, and genetic information in this chapter, describe how the gecko's coloration might have evolved?

Identify the theme or themes exemplified by (a) the sharp quills of a porcupine, (b) the development of a multicellular organism from a single fertilized egg, and (c) a hummingbird using sugar to power its flight.

For each theme discussed in this section, give an example not mentioned in the text.

Explain why “editing” is a metaphor for how natural selection acts on a population’s heritable variation.

Referring to Figure 1.2 provides a possible explanation for how, over a very long time, the green warbler finch came to have a slender beak.

The three domains you learned about in Concept 1.2 can be represented in the tree of life as the three main branches, with three subbranches on the eukaryotic branch being the kingdoms Plantae, Fungi, and Animalia. What if fungi and animals are more closely related to each other than either of these kingdoms is to plants, as recent evidence strongly suggests? Draw a simple branching pattern that symbolizes the proposed relationship between these three eukaryotic kingdoms.

What qualitative observation led to the quantitative study in Figure 1.25?

Contrast inductive reasoning with deductive reasoning.

Why is a natural selection called a theory?

In the deserts of New Mexico, the soils are mostly sandy, with occasional regions of black rock derived from lava flows that occurred about 1,000 years ago. Mice are found in both sandy and rocky areas, and owls are known as predators. What might you expect about coat color in these two mouse populations? Explain. How would you use this ecosystem to further test the camouflage hypothesis?