Ecology

What is a abiotic factor?

A nonliving part of an organism's habitat (ex: bench)

natural selection

A process in which individuals that have certain inherited traits tend to survive and reproduce at higher rates than other individuals because of those traits.(individuals)

Explain how dispersion patterns could differ depending on scale. For example, why might you see a random dispersion pattern at small scale but a clumped dispersion pattern at a larger scale?

At a smaller scale, a species of an organism may be random from the way they appear to exist (due to the spread of their seed), but on a larger scale, it seem to be a clumped pattern. This may be because of the availability of resources. If their seed lands in an area without suitable resources, it simply wont be viable enough for it to exist there. Over time, clumped areas of random dispersion may appear.

COLLAPSE 12. What information can you get from looking at the age structure of a population?

From observing the age structure of a population, one can interpret birth and death rates, and possibly the reasoning behind these trends. For instance, a rapid growth pyramid illustrates high birth rates and and perhaps high death rates if the top of the pyramid is thinner. The age distribution is more prevalent starting from birth and the markings on the pyramid get shorter as age ascends. Because the birth and death rate are nearly equal, there won't be much change within the population.

What is the struggle of existence.

Struggle for existence: The idea that more offspring will be produced than can survive to reproductive age, and those that do may not produce the same amount of offspring.

How does the age structure of a population that is rapidly increasing in size differ from one with very slow or no population growth over time?

The age structure of a population that is rapidly increasing in size likely is experiencing a demographic transition. A demographic transition could account for sanitation use, a better healthcare system, or a better supply of food. For a population experiencing a very slow or no population growth at all may be suffering from a lack of resources to sustain the births.

Evolution

The gradual change in a species over time(population)

Why is variation in populations is necessary for evolution to occur. How is this variation generated?

Variations in populations is necessary for evolution to occur because without differences or adaptations, all species could possibly be the same or eventually become extinct due to specie's being unfit for survival in their given environment. Variations starts on an individual level which cascades into a generation overtime, a population level. For example, the red-bellied black snake population that was exposed to poisonous toads adapting to not viewing toads in general as a means for a meal. Also, over time, it made way for only the snakes who were larger, changed their eating habits, and reduced their speed as the snake type to exist today for they can handle poison exposure. The phrase "survival of the fittest" fits directly into this context.

metapopulation

a group of spatially distinct populations that are connected by occasional movements of individuals between them

What is "selection pressure"? How does selection pressure cause evolution in populations over generations. Give an example of this process.

election pressure is the environmental change a population has to adapt to in order to survive. A factor changes in the environment and those with phenotypes able to overcome and adapt to those changes will survive longer and reproduce causing gradual changes in phenotypes in the population

Which of the three dispersion patterns is most common? Which is least common? Why?

f the three dispersion patterns, the most common pattern is clumped because it all depends on the availability of resources. Typically, organisms of a population do not all stick together in one group for the entirety of their existence, rather they form relationships with other organisms to increase survival chances. The least common would be the random dispersion - if the organism is not a plant species, this could be seen as a vulnerable, not-smart method for survival; however, dandelions cannot choose where the wind blows their seeds and in terms of this plant, there is nothing very threatening about their seeds being spread out.

What is a biotic factor?

living factor

List and explain behavioral or ecological factors, other than those mentioned in lecture, which would create clumped, uniform or random dispersion patterns. Provide ONE example and let other students provide additional examples.

n example of a clumped dispersion pattern could be deer - often times, they stick together in groups ranging from all ages especially in the Maryland population of deer. An example of a random dispersion pattern could be plants with seeds affected by wind. For example, sunflowers. An example of uniform dispersion would be ducks in a pond.

Demography

the study of births and deaths