Population Distribution and Survivorship Questions and Answers Worksheet for AP Environmental Science.
- Compare the survivorship curves for males against those for females. Does the data support the trend that women tend to live longer than men? Support your statement with explanations of why or why not?
It appears that women live longer than men, according to the data. The graph supports this by showing that there is a later loss in women compared to men.
- Analyze and compare the mortality rates for the older age groups. In general, why should these rates be higher than average?
These rates should be higher because of the fact that as someone gets older; they get more frail and weaker. Their immune system is weaker and they generally start deteriorating.
- How would current survivorship curves differ from those from the 1800’s?
Currently there have been many advances in medicine that helps make lives longer and help more people reach older age.
- How would the survivorship curves of a developed country differ from those of a less developed one?
A less developed country will have a survivorship curve closer to early loss as compared to a developed country. This is due to higher poverty rates, higher infant death rates and lack of medical care.
- How could survivorship curves be used to make judgments about environmental and health conditions in each of the countries?
Survivorship curves can help countries see how long people live and helps make assumptions about how the economic situation is in that country.
- Humans are generally classified as forming a Type I survivorship curve. What does that imply for humans?
This implies that humans generally have a late loss curve as compared with other animals.
- Name some other organisms that are generally Type I. What are the distinguishing characteristics of Type I organisms?
Mammals are usually Type I organisms, such as whales and elephants. Type 1 organisms have less children, take care of them more, and reproduce later in life.
- What does it mean to have a Type II survivorship curve? Give two examples of organisms that are generally Type II.
Having a Type II survivorship curve means there is a constant loss throughout life. Some birds have this kind of curve.
- What does it mean to have a Type III survivorship curve? Give two examples of organisms that are generally Type III.
Having a survivorship curve means early loss. This means that most of the organisms die in the beginning of their lives with few surviving to adulthood.
- Review the meanings of the terms r-strategist and K-strategist. How are the life cycles of these strategies different?
K-strategists tend to have late loss while r-strategists usually have early loss curves. K-strategists organisms are large, have late reproduction and few children, and care for their children. R-strategists have high reproductivity rates and early loss and short generation time.
- Describe what type of survivorship curve the two should have. Why? Why do we use the symbols “r” and “K” for these strategies?
K-strategists should have a late loss curve (Type I) while r-strategists should have an early loss curve or Type III. K-strategists are called that due to the fact that K-strategists are close to carrying capacity (K) and r-strategists are close to intrinsic rate of growth (r).