Background info: The Canadian Cancer Society provides some statistics about the

Question

Background info: The Canadian Cancer Society provides some statistics about the incidence of skin cancer in Canada. In 2009, there were 5,000 new cases of malignant melanoma diagnosed, and 940 people died of this dangerous form of skin cancer. During 2009, there were 75,100 Canadians diagnosed with non-melanoma skin cancer, and 270 people died of this disease. The median age of diagnosis is 59 for malignant melanoma and 60 for non-melanoma skin cancer. Skin cancer risk increases with UV light exposure, and light skinned Caucasians have a higher incidence of skin cancer than other ethnic groups in Canada.

Q. With reference to the information provided above, explain why skin cancer alone may not have a sufficient impact on fitness to explain variation in human skin colour.

I'm really confused by this question. I'm thinking it is because variation in skin color is influenced by other factors depending on geographic distribution. Am I on the right track? Thanks in advance.

Explanation / Answer

You're definitely on track with the geographic distribution. People closer to the equator will obtain higher UV dosages with the same exposure time. They also aren't taking into account other things like lifestyles that cause people to be exposed to more UV rays than average. This would include people that tan, and also people like construction workers and lifeguards that are outside for extended periods of time.

Related Questions

Navigate

• Browse (All)
• Browse B
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.