Chapter 2 Lesson 1 Flashcards
What are the three main population metrics?
- Density
- Distribution
- Size
What is population size?
The total number of individuals in one population
What is population density?
The amount of individuals of one population in one specific area
What is population distribution?
The way individuals of the same population are spread out
What is the difference between population density and distribution?
Density is the amount of one population in an area while distribution is the way they are spread out
What is the definition of population?
All of the organisms in the same place at the same time that can reproduce together
What distribution pattern would this likely represent. . .
Resources are scarce and as a result species are very territorial?
Uniform Distribution
What distribution pattern would this likely represent. . .
A certain fish species tends to gather in large groups to avoid being singled out and eaten by predators?
Clumped Distribution
What distribution pattern would this likely represent. . .
The seeds of a plant species are distributed by wind in a field where conditions are uniform?
Random Distribution
What type of distribution would random sampling work best for?
Uniform Distribution
What are the factors that affect population size?
- Abiotic Factors
- Biotic Factors
- Intrinsic Factors
What are some abiotic factors that influence population size?
- Percipitation/Water
- Soil/Nutrients
- Sunlight & Temperature
What are some biotic factors that influence population size?
- Other living organisms
+ Prey (Food)
+ Competitors
+ Preditors, Parasites, Desiese
What is one intrinsic factor that influences population size?
- Adaptations
What are some ways to count population?
- Direct Counting
- Indirect Counting
- Random Sampling
- Mark and Recapture
How do you do direct counting?
You count every individual
How do you do indirect counting?
Count every individual in a hive, burrow, town, etc and count number of hives, buttons, towns, etc.
What is the formula for random sampling?
of organisms in sample divided by the area of sample = total # of organisms divided by the total area
What is the formula for mark and recapture?
Total marked divided by total # of organisms = total of recaptured with marks divided by # of recaptured organisms
You are out with some scientists one night and capture and mark 20 wolves. One week later you come back and capture 20 wolves, 4 of these wolves were previously marked. How many wolves are there in this population?
There are 100 wolves in this population
The size of each square is 2 cm x 2 cm. If the field is 840 cm^2 what is the estimated size of the population?
3 - 4 -
- - - 2
1 5 - 6
- - 2 -
690 organisms
