Why does the need for living space cause problems for some organisms?

Living space is the amount of room an animal needs. The amount of space needed varies from species to species. 

A shortage of space can have serious consequences. For example: When muskrats get overcrowded, an outbreak of disease usually occurs. Because the animals are in closer contact with each other, the disease spreads very rapidly and it causes the population to thin. 

When a living space of certain animals gets destroyed or taken then the animals either have to move or die. They cannot move because in any given area, animals reproduce and their population increases until a shortage of resources stops the increase. So many end up dying. 

Habitat is the key to the survival of wildlife, and we are the keys to the survival of habitat. 

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