nothing
Declined
Its hard to say but 1000s have happend
Backstory
At this occasion is happening now. On this occasion happend in the past.
The word "happened" is the past tense form of the verb "to happen".
I was born!
because they have important things and they have historical story about what happend in the past
Earthquakes happend
that died
a dholphin is a dog/dolphin, i spent years studing dholphins.this happend years ago.
the American revolation war started and ended in these years
Yes, it has caused (in the past) some more cold-reliant species to die. But, it has also cause some new species (like insects) to come up in the past as well. So some of both. *(Note: This is millions of years ago, NOT the current global warming.)