The Following Table for a Species of Plant That Has

question 32

Essay

The following table for a species of plant that has four life stages was constructed from research done in the 1960s.

$$\begin{array} { | l | l | l | l | } \hline{ \text { Age Class } ( x ) } & \text { Survival Rate } \left( \mathrm { s } _ { \mathrm { x } } \right) & \text { Survivorship } \left( \mathrm { l } _ { \mathrm { x } } \right) & \text { Fecundity } \left( \mathrm { b } _ { \mathrm { x } } \right) \\\hline \text { Seed } & 0.3 & 1.000 & \\\hline \text { Seedling } & 0.2 & 0.300 & \\\hline \text { Small adult } & 0.1 & 0.060 & 20 \\\hline \text { Large adult } & & 0.006 & 50 \\\hline\end{array}$$
Forty years later, biologists went back to the same site and determined the life table for the population, shown in the following table. On account of changing climatic conditions, seed survival decreased from 30 percent to 10 percent. However, these changing climactic conditions also cause large adults to produce four times as many seeds, so that they now produce 200 seeds. All other variables stay the same.
$$\begin{array} { | l | l | l | c | } \hline { \text { Age Class } ( x ) } & \text { Survival Rate } \left( \mathrm { s } _ { \mathrm { x } } \right) & \text { Survivorship } \left( \mathrm { l } _ { \mathrm { x } } \right) & \text { Fecundity } \left( \mathrm { b } _ { \mathrm { x } } \right) \\\hline \text { Seed } & 0.1 & 1.000 & \\\hline \text { Seedling } & 0.2 & 0.100 & \\\hline \text { Small adult } & 0.1 & 0.020 & 20 \\\hline \text { Large adult } & & 0.002 & 200 \\\hline\end{array}$$

Explain whether the change in climate is beneficial or harmful to this plant population based on these tables. Be sure to reference any relevant calculations you should make and explain the relative importance of the decreased seed survival and increased seed production.

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Definitions:

Stress

A physical, mental, or emotional factor causing bodily or mental tension, which can arise from any event or thought that makes one feel frustrated, angry, or nervous.

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The process of breeding plants and animals for particular genetic traits, to enhance or develop specific characteristics.

Genetic Method

An approach in psychology that examines the influence of genetics on behavior and traits, studying how inherited characteristics impact individual differences.

Pancreas

A dual-purpose gland under the stomach that performs both digestive and endocrine functions.