What is extinction and why does it occur?

Extinction is the dying out of an entire species. Extinctions have occurred regularly throughout Earth's history. At certain times, major climate changes, catastrophic events such as large meteorite impacts, or massive volcanic activity on earth have caused the Extinction of large numbers of species.

children tend to take more after their grandparents more than their parents. it’s the dna you received that was passed down to you somewhere in your family. maybe one of your grandparents had/has straight hair and you might have gotten it from them.

is this a psat question, if so do not cheat try your best.