Question

Teosinte, on the left, is a Mexican wild grass that is considered to be a parent plant of modern corn, on the right. Over time, farmers selected larger seeds from the teosinte to plant in next year's crop, eventually leading to larger kernel size in corn. This is known as artificial selection. Evaluate the examples and select those that do NOT show artificial selection. CHOOSE TWO. Responses A White rabbits have a low survival rate in nature, because it is easy for predators to spot them. White rabbits have a low survival rate in nature, because it is easy for predators to spot them. B Penguins with higher body fat tend to survive nesting in the Antarctic winter, while leaner penguins often die. Penguins with higher body fat tend to survive nesting in the Antarctic winter, while leaner penguins often die. C A gene for disease resistance in fir trees is transferred to pine trees using modern DNA technology, allowing farmers to maximize pine tree growth. A gene for disease resistance in fir trees is transferred to pine trees using modern DNA technology, allowing farmers to maximize pine tree growth. D Because big game hunters sought elephants for ivory, often poaching those with the biggest tusks, more African elephants today naturally lack tusks compared to the elephant populations 100 years ago. Because big game hunters sought elephants for ivory, often poaching those with the biggest tusks, more African elephants today naturally lack tusks compared to the elephant populations 100 years ago. E In subsaharan Africa, genetically modified grass varieties that carry genes for disease and drought resistance are now available to farmers, providing more sustainable food sources for their livestock. In subsaharan Africa, genetically modified grass varieties that carry genes for disease and drought resistance are now available to farmers, providing more sustainable food sources for their livestock.

Answer 1

Responses B and D do not show artificial selection; B is natural selection, and D is unnatural selection. Both cases do not involve human breeding interventions aimed at passing on traits but rather survival and poaching impacts, respectively.

Step-by-step explanation:

The process by which teosinte was transformed into modern corn through selective breeding is a prime example of artificial selection. Over time, indigenous people selected and planted seeds from teosinte that had desirable traits such as larger seeds, unwittingly altering its genetics to eventually produce maize. The two examples from the student's question that do NOT show artificial selection would be:

• B. Penguins with higher body fat tend to survive nesting in the Antarctic winter, while leaner penguins often die. This is an example of natural selection because it involves survival of the fittest in a natural environment without human intervention.
• D. Because big game hunters sought elephants for ivory, often poaching those with the biggest tusks, more African elephants today naturally lack tusks compared to the elephant populations 100 years ago. This is a case of unnatural selection, where human activity impacts natural selection, but it is not artificial selection as the humans are not breeding the elephants to pass on specific traits.

Responses A, C, and E involve human intervention to select or modify specific traits intentionally, fitting the criteria for artificial selection.