If the numbers of a species begin to decline dramatically, the species becomes known as an "endangered" species. When the numbers decline so far that the species no longer exists, the species is known to be "extinct."
Sexual Frustration.
The decline of any population will perturb the ecological balance. If the number of one particular species declines, then any species that preys on it will lose some of its food supply and so its population may decline as well. A species in parasitic or symbiotic relationship is also likely to decline. On the other hand, any species which lives in competition - for food or other resources - would face less competition and so its numbers are likely to increase.
The human body begins to decline at an old age or it can decline due to the lack of nutrition.
Factories begin because of the working conditions.
Between 2000b.c.and 1500b.c.
Poachers hunting this endangered species has made the number of their population decline.
Smaller natural habitat, more human encroachment, and less food are the three main causes for the decline of the frog species.
the 1970s
Between 2000b.c.and 1500b.c.
Immigration numbers did not decline.
For once, it would be a good thing to see a species decline a bit. The adaptable coyote is found now in great numbers where it is not native, and has become a threat to native species and livestock, even children.
black people