Population bottlenecks are when population size reduces for a short period of time. Overpopulation may indicate any case in which the population of any species of animal may exceed the carrying capacity of its ecological niche.
The name zirconium comes from the mineral zircon, which is the most important source of the metal. The largest deposits of this mineral are found in Australia, Brazil, Russia, India, South Africa and the United States. Australia and South Africa are the largest miners of the mineral.
The first eon in Earth's history, the Hadean, begins with the Earth's formation and is followed by the Archean eon at 3.8 Ga. The oldest rocks found on Earth date to about 4.0 Ga, and the oldest detrital zircon crystals in rocks to about 4.4 Ga, soon after the formation of the Earth's crust and the Earth itself.