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1)  Fritz Müller 2) Generalist-Raccoon and fruit fly Specialist-Panda and koala

What is the difference between tailings and overburden?

Overburden is a cover of loose material (soil, gravel, etc) that covers a mining site. it can be [size=200]used as construction material, or may be used after mining to restore natural conditions.[/size]Tailings are a mixture of water and finely ground rock that are left after mineral concentrates are removed. They are [size=200]permanently stored in a secure facility after mining.[/size]

Overburden is the soil, rock, and ecosystem above any resources of economic or scientific interest. By removing the overburden to get to the resource, most often, coal, then an entire ecosystem can be destroyed. Tailings are the materials left over after the valuable portion has been removed from the ore.

List 3 major causes of desertification and describe in detail.

1-Agriculture. Harvesting plants continuously prevents the roots of any vegetation from holding the topsoil down for a long period of time. Also, the perpetual harvest of crops depletes nutrients in the soil, so eventually, nothing else can grow. 
2-Overgrazing. Livestock can clear vegetation very easily, so that the land becomes barren. When something finally grows, it is eaten almost immediately, so there are no plants protecting the topsoil from being eroded. Once the topsoil is gone, the land becomes infertile and dry. 
3-Resources. People clear land of trees and plants for timber or fuel. Without the plants, the soil is eroded. Basically, all the major causes of desertification involve clearing vegetation.

Name three differences between an r-selected and K-selected species.

R selected species - most of their energy is focused on reproduction, high reproductive rates, populations experience rapid growth, mature quickly, offspring have very little postnatal care
K selected species - most of their energy is focused on growth, populations have a constant size, low reproductive rates, offspring require extensive postnatal care until they reach maturity