2.1 Flashcards
Define a population.
Population is the number of living animals or plants in the same area at the same time that can reproduce with each other.
Define population density.
The number of individuals/area.
Define population distribution.
The pattern in which organisms of a population are spread throughout the range.
What are the types of distribution, how are they different from each other, and what might cause a population to be in those formations.
Uniform is where species are in a predictable pattern, evenly spread throughout the entirety of the range of the population. A uniform distribution might occur because resources are scarce and the organisms in the population have to stay apart, or because nothing can grow close to a certain plant, or the animals are every territorial. Clumped distribution is where the organisms are in separate groups, with none alone. A clumped distribution might happen because staying together helps a species to survive. Random distribution is where the organisms in a population are spread across the range very unevenly, with no real pattern. A random distribution can happen when plants’ seeds are scattered by the wind to random areas, or when resources are plentiful and the animals do not need to stay together to survive, and they are not territorial.
What is the population density in a population where there are 8,000 trees in 32 square miles?
8,000/32=250 trees per square mile.
What is the estimated size of a population where each quadrant is 5 meters by 5 meters, the total area is 625 square meters, and in 5 separate samples there were 7, 3, 8, 9, and 5 members of the population?
5x5=25 square meters
7+3+8+9+5=32
32 x
—– = —–
125 625
625(32)=125x
20,000=125x
160=x
What is the estimated size of a population where 40 birds were caught and marked, then 3 samples of 80 birds had only 22, 14, and 27 marked birds
14+22+27=63
80x3=240
40 marked 63 recaptured
birds marked birds
—————— = ———————
x 240 caught
birds
63x=240(40)
63x=9600
About 152 birds
