Population+Collaboratioin

Populations  1. Define a population? Give an example. What does a population study focus on? Tyia  **Population:** A group of organisms of the same species that live in a specific geographical area and interbreed.

many individuals are born, how many die, and so on.
 * A population study focuses on:** A population as a whole—how

** Example: ** All of the bass living in a pond during a certain period of time make up a population because they are isolated in the pond and do not interact with bass living in other ponds. 2. Describe the procedure for estimating population sizes from the book. Describe the mark-recapture method and give an example of how it could be used(Will have to go to the Web for this one!). Justess 3. What is population density? Give a formula. Give an example. Bridgett  Bridgett Donaldson What is population density?

Population density- measure how crowded a population is

Formula= population /total area

Example- the population density of humans in the united states is about 30 people per kilometers squared

4. What is dispersion? Describe and find pictures of random, uniform and clumped dispersion. Erin __Dispersion__ is the spatial distribution of individuals within the population. In a __clumped dispersion__, individuals are clumped together. Cjlumped dispersions often occure when resources such as food or living spaces are clumped. They may also occur because of a species' social behavior, such as when animals gather into herds or flocks. In A __Uniform Disperson__//,// indivivduals are sperated by a fairly consistent distance. Uniform distributions may result from social behavior in which individuals within the same habitat stay as far away from each other as possible. As an example a bird may locate it's nest so as to maximize the distance from the nests of other birds. In a __Random Dispersion__, each individuals location is independent of the locations of other individuals in the population. Few populations are truly randomly dispersed. Animals more often show a degree of uniformit or clumping.

-Birth rate- the number of births that occur in a period of time in a given area.
6. Define an age structure diagram. Find pictures of age structure diagram and write if each population is growing, getting smaller or showing zero growth. May need to go the Web for this one, the book does not give much information. Deja Deja Hadley 7. Describe the three types of survivorship curves. Give an example of organisms for each. Find a labeled picture similar to the one in the book. Stanford 8. Define growth rate. What four processes determine a populations growth rate. What is the formula for growth rate? Mattison Four Processes- birth, death, emigration, and immigration
 * Age structure diagram- this diagram show the population between female and males in a certain population in a graphic form.
 * The picture below shows the population form 1991 to 2001, the diagram shows that the population had growth.
 * Growth rate-** an expression of the increase in the size of an organism or population over a given period of t

Formula- birth rate-death rate=growth rate 9. Define exponential growth. What shape does the graph take? Insert a picture of a line graph showing exponential growth. Matthew Exponential growth: Pattern of increase in number due to a steady growth rate.

The graph curves up because the population is increasing. 10. Does exponential growth model apply for all populations? Define and give an example of limiting factors. Victoria Victoria Hurst No, the exponential growth model apply for all populations. __Limiting Factor:__ refers to any condition that is required by a species which becomes in sufficient or absent in a habitat. Examples: Food and Water 11. What does the logistics growth model look like(find a picture)? What letter is used to describe logistics growth. Define carrying capacity. What is the symbol for carrying capacity? Kendyl  carrying capacity-maximum population that an area will support without undergoing deteriation. The symbol is k.﻿ logistic growth-curve [|fig6.gif] 12. Define density independent factors and density dependent factors. Give several examples of each. May need to go to the Web for more examples. Michael Density Independent and Dependent Factors andrew parker 9/23 Mr. Beaty

__Density independent factors are basically abiotic factors such as weather, temperature, pH, and so on. It is a factor that affects the population independent or regardless of the population density.__

__Density dependent factors are A whose effects on the size or growth of population vary with the__ __  __


 * [[file:///dictionary/Population_density|__weather,__ ]]
 * [[file:///dictionary/Population_density|__ph,__ ]]
 * [[file:///dictionary/Population_density|__temperature,__ ]]
 * [[file:///dictionary/Population_density|__forest fires,__ ]]
 * [[file:///dictionary/Population_density|__pollutants__]]
 * [[file:///dictionary/Population_density|__parasitism__]]
 * [[file:///dictionary/Population_density|__availibilty of food__]]
 * [[file:///dictionary/Population_density|__migration__]]
 * [[file:///dictionary/Population_density|__hibernation__]]
 * [[file:///dictionary/Population_density|__preditation__]]
 * [[file:///dictionary/Population_density|__disease__]]

13. **Marcus:** The two types of population is Density-dependent factors and Density-independent factors. **Density-dependent factors** include resource limitations, such as shortages of food or nesting sites, and are triggered by increasing population density. **Density-independent factors,** such as weather, floods, and fires, reduce the population by the same proportion, regardless of the population’s size. The increased lynx population then ate more hares, so the hare population decreased. With less food, more lynxes starved and the lynx population declined, allowing the hare population to increase and start the cycle over again. The hare population depended on some other organism. As the lynx ate more the food source started to decline.

14. Why is it so bad to have small populations of organisms? What is inbreeding? Why is it a bad thing? Caroline ** Why is it so bad to have small populations of organisms? **
 * Environmental disturbances such as storms, fires, floods or diseases can kill off an entire population and leave only few individuals remaining.
 * The members of a small population may be descended from only a few of individuals, this increases the likely hood of inbreeding, or mating with relatives.
 * Offspring of related parents are more likely to have diseases, and have a shorter life span.
 * Also, it may reduce the populations ability to adapt to changing environmental conditions.

** What is inbreeding? **
 * I nbreeding- mating with relatives.

**Why is it a bad thing?** Zach Webb (not zack)- The Bottleneck effect is when a large number of animals in the same species die or become unable to produce, but not all. It can occur
 * Inbreeding can lead to some diseases, may reduce the populations ability to adapt to their environmental conditions.
 * Have fewer offspring
 * Decrease genetic availability over time.

(thats my picture) __**The population of humans on planet earth:**__ Will White
 * Humans have been around for approximately 2.1 million years.
 * Gradually, the human population has been growing bigger and bigger over time and in the past couple of miliniums, it has grown alot.

17. What are the characteristics of developing nations? Give examples. -Dani-

Developing Countries: in general, these countries are usually poorer, and their populations are growing faster. -Such as... Most countries in South America, Asia, Central America, and Africa.

Developed Countries: usually have better education, are healthier, and have a longer lifespan. -Such as... United States, United Kingdom, Australia, and Canada.

18. Describe the Industrial Revoluluton. How did this effect the human population. How is our population growing totday? Alexus **Hunter-Gatherer Revolution (Neolithic Revolution)** The Neolithic Revolution began about 12,000 years ago. The hunter-gatherers had low population densities because there wasn't enough food to hunt. When the food supply ran out, they had to move quickly in order to find more food to survive. The population fluctuated rapidly because of natural selection, or survival of the fittest.

**British Agricultural Revolution** The British Agricultural Revolution helped drive the Industrial Revolution. It began in the 18th-19th century. The population reached 5.7 million and the new agricultural advances helped to sustain population.

**Industrial Revolution** <span style="font-family: Arial Narrow,sans-serif; font-weight: normal; margin-bottom: 0in;">The Industrial Revolution began around 1760 and ended around 1850. This revolution began in England and included changes in agriculture, textiles, metal, manufacturing, transportation and economic and social structure. During this time, Europe's population rose from about 100 million to about 400 million over this period of time because of all the innovations, and other countries began to follow suit. <span style="font-family: Arial Narrow,sans-serif; font-weight: normal; margin-bottom: 0in;">Our population is growing today because of our many ecological, technological, and agricultural innovations. These innovations are helping to sustain and expand our population. - Alexus Bazen  19. How many people are on earth? What is the growth rate for the human population? How many people are expected to be on earth by the end of your life time? Justin The current population is 6.8 billion people. The population is increasing by 203,800 people every day. By the year 2020, the estimated population is 8 Billion. By the year 2050, the estimated population at this rate will be 10.5 billion people. 20. What is the carrying capacity for earth? Do you think that we will ever reach it? Will need to research this one on the Web. There are many proposed answers for this one. <span style="color: #800080; display: block; font-family: Calibri,sans-serif; font-size: 13pt; line-height: 0.19in; margin: 0in 0in 0in 0.5in; orphans: 2; padding-bottom: 0in; padding-left: 0in; padding-right: 0in; padding-top: 0in; text-align: left; text-indent: -0.25in; widows: 2;">__** Sarah **__

<span style="color: #000000; display: block; font-family: Calibri,sans-serif; font-size: 13pt; font-weight: normal; line-height: 0.19in; margin: 0in 0in 0in 0.5in; orphans: 2; padding-bottom: 0in; padding-left: 0in; padding-right: 0in; padding-top: 0in; text-align: left; text-decoration: none; text-indent: -0.25in; widows: 2;"> ... Carrying capacity is not a fixed number.

<span style="color: #000000; display: block; font-family: Calibri,sans-serif; font-size: 13pt; font-weight: normal; line-height: 0.19in; margin: 0in 0in 0in 0.5in; orphans: 2; padding-bottom: 0in; padding-left: 0in; padding-right: 0in; padding-top: 0in; text-align: left; text-decoration: none; text-indent: -0.25in; widows: 2;"> ... Estimates put Earth's carrying capacity at anywhere between 2 billion and 40 billion people

<span style="color: #000000; display: block; font-family: Times New Roman; font-weight: normal; line-height: 0.19in; margin: 0in 0in 0in 0.5in; orphans: 2; padding-bottom: 0in; padding-left: 0in; padding-right: 0in; padding-top: 0in; text-align: left; text-decoration: none; text-indent: -0.25in; widows: 2;"> … <span style="font-family: Calibri,sans-serif; font-size: 13pt;">I believe that we will one day reach earth's carrying capacity.

<span style="color: #000000; display: block; font-family: Calibri,sans-serif; font-size: 13pt; font-weight: normal; line-height: 0.19in; margin: 0in 0in 0in 0.5in; orphans: 2; padding-bottom: 0in; padding-left: 0in; padding-right: 0in; padding-top: 0in; text-align: left; text-decoration: none; text-indent: -0.25in; widows: 2;">The population is growing rapidly and I believe we will run out of resources if it continues. 21. What are the characteristics of developed nations. Give examples. Nil You have two-both are easy :)  People in developed countries are better educated, healthier, and live longer then the rest of the worlds population. 22. What is the demographic transition model? Include a picture. Nil  <span style="display: block; font-family: Times New Roman,serif; text-align: left;">The __**demographic transition**__ model shows how these population changes happen. The theory behind the model is that industrial development causes economic and social progress that then affects population growth rates. The 3 stages are birth rate, death rate, and population size. In the first stage of the model, the birth rate and the death rate are both at high levels, and the population size is stable. In the second stage, a population explosion occurs. Death rates decline as hygiene, nutrition, and education improve. But birth rates remain high, so the population grows very fast. In the third stage, population growth slows because the birth rate decreases. As the birth rate becomes close to the death rate, the population size stabilizes. In the fourth stage, the birth rate drops below replacement level, so the size of the population begins to decrease. It has taken from one to three generations for the demographic transition to occur in most developed countries. 23. Answer question 6 from pg 392. 24. Answer question 7 from pg 392. 25. Answer question 8 from pg 392