World war 1 broke out in 1914 because a group of Serbian nationalists (The Black Hand) assassinated the duke of Austria-Hungary. Austria -Hungary threatened Serbia with a bunch of wishes that they wanted Serbia to due for them. Due to the treaty between Serbia and Russia, Serbia said no. Germany, who had a treaty with Austria-Hungary threatened to attack if Russia mobilized its army. Russia did and Germany invaded Belgium. This brought Great Britain and France into the war.
Nigeria is home to hundreds of ethnic groups
The theory of natural selection was explored by 19th-century naturalist Charles Darwin. Natural selection explains how the genetic traits of a species may change over time. This may lead to speciation, the formation of a distinct new species.
