Final answer:
Researchers at the University of Florida found that greyhounds ran slower when given high doses of vitamin C, contradicting the belief that it would enhance their speed. The role of vitamin C in iron absorption and cold prevention is noted, emphasizing a distinction between dietary supplements and natural adaptations.
Step-by-step explanation:
The University of Florida conducted research on greyhounds to study the effects of vitamin C on their running speed. The investigations challenged the belief that high doses of vitamin C would enhance running performance, as the greyhounds actually ran more slowly. This outcome calls into question the common practice of supplementing racing dogs with large amounts of vitamin C.
Vitamin C is known for its role in iron absorption from the intestine and for potentially reducing the duration and severity of the common cold. While citrus fruits like lemons and oranges, along with fresh green vegetables and other fruits, are rich sources of vitamin C, an excess intake of this nutrient may not always confer expected benefits, as seen in the greyhound study. In the context of cognitive learning and natural selection, it is known that different species can learn tasks such as maze-running, and adaptations like increased running speed can be developed over time through the process of natural selection. However, the greyhound study suggests that dietary supplements cannot substitute for these complex biological and evolutionary processes.