Question

in a year, a population of lions had four births, two deaths from disease, one natural death, five emigrations, and five immigrations. in the same year, a population of zebras had five births, three deaths, four emigrations, and one immigration. which best explains the data?
zebras and lions are both experiencing a negative population growth.
zebras and lions are both experiencing a positive population growth.
the zebras have a higher population growth than the lions have.
the zebras have a lower population growth than the lions have.

Explanation:

Step1: Calculate population change for lions

Births = 4, Deaths = 2 + 1 = 3, Emigrations = 5, Immigrations = 5.
Population change = (Births - Deaths)+(Immigrations - Emigrations) = (4 - 3)+(5 - 5) = 1+0 = 1.

Step2: Calculate population change for zebras

Births = 5, Deaths = 3, Emigrations = 4, Immigrations = 1.
Population change = (Births - Deaths)+(Immigrations - Emigrations) = (5 - 3)+(1 - 4) = 2+( - 3)= - 1.

Since the population change for lions is 1 (positive but very small increase) and for zebras is - 1 (negative change). Considering the overall context of population growth (usually a significant positive change is considered as positive growth in ecological terms for such simple models), both can be seen as having negative - like trends (zebra has a clear negative change and lion has a negligible positive change which might not be sustainable or significant enough for a 'positive growth' label in a broader sense). So the first option "Zebras and lions are both experiencing a negative population growth" is the best explanation.

Answer:

Zebras and lions are both experiencing a negative population growth.