Friday, October 24, 2014

Population Dynamics Summary Questions

Population Dynamics Summary Questions

Using an example, describe why population could not increase forever.

An example of why population cannot increase forever is, in the African plains buffalo are wild and if there were no lions the buffalo would overpopulate the plains and they would not all be able to survive or they would make other creatures die or have to move out.
But since there are lions in the plains (The buffalo's predator) they kill and eat the buffalo and their offspring, it is a sad truth but it is so all other creatures can survive in a way, including the buffalo.

What are 2 factors that determine whether a population increases or decreases. (Use each factor in a one sentence example.

Two factors that determine whether a population increases or decreases are Carrying capacity and prey and predators.
Carrying capacity is a factor because its determines how many animals in a species can be supported in an ecosystem. for example fish in a pond, you could fit hundreds, maybe thousands of fish in a pond but all of them wouldn't be supported by the ecosystem. to be supported they need to be fed and be able to have offspring to be supported.
Another factor is predator and prey, all animals either have prey or predators except humans, they either eat or get eaten, that determines whether any increases or decreases happen in the population.

Give me a reason why the human population of earth has continued to increase so much for the past hundred years?

One reason of why the population of earth has increased so much is because we have become more advanced in medicine and technology. We no longer live in fear of animals everyday or need to build shelter to survive. When we get sick we go to the doctor for medicine, when animals get sick they lie in the forest and die. we have all these things to keep us alive while we are making a world where everything will die except us.

Wednesday, October 22, 2014

Symbiosis

Symbiosis

Definition of symbiosis: The definition symbiosis is how two organisms benefit or harm each other for example a crocodile benefits by having its teeth cleaned while a small bird benefits by getting free scraps. by eating the scraps.

Mutualism: Mutualism is a type of symbiosis in which both organisms benefit. For example a deer might eat some berries and get nutrients while the berry seeds get pooped out somewhere else where another bush will grow. Both organisms benefit because the deer gets to eat and there are more berries spread around. Everyone wins.

Commensalism: Commensalism is a type of symbiosis where one organism benefits and the other one is neither benefited or harmed. For example a peach benefits from the tree because the peach gets protection from anything on the ground trying to eat it because it hangs on one of the tree's high limbs and it also get enough nutrients to grow from the tree, the tree gets nothing but doesn't have a problem with that.

Parasitism: Parasitism is a type symbiosis where one organism benefits and the other is actually harmed. For example when you get bitten by a mosquito the mosquito gets the blood it wanted and the human might get a disease on top of the the fact that it lost blood.

How this connects to class: This connects to what we have been doing in class because food webs have everything to do with symbiosis because it is how one organism or species affects one another, and a food web is a whole ecosystem of things affecting one another. 




Friday, October 3, 2014

Discussion questions

Discussion Questions

Why do we as scientists build food webs?

We build food webs to see how energy is being transfered throughout nature and and its ecosystems. Food webs are also built to show how the animals and world would react to a small or big change like the increase in an animals population or the decrease in anothers. They are a way to see what will happen in extreme situations.

Give and example of how one change might effect the entire ecosystem

One example of a change would be if the bear population decreased the fish population would increase and then the otters population would increase and then the alligator population would increase which in turn would make the population of everything the alligator eats decrease and so on.
The balanced ecosystem from before would shift but it would be a new balance. Changed but balanced none the less

Food web