It is because we are, this is the first time in human history, where we have technology and science is widely accepted, without being ridiculed by religious figures.
I'm assuming it would be Population Density. My class never covered this subject greatly, but the definition is "Population density is a measurement of population per unit area or unit volume;" which sounds like what you are looking for.
Hope this helps!
-Payshence
YOU MUST COMPLETE ALL WORKSHEETS IN ORDER.
YOU WILL NOT RECEIVE THE FOLLOWING ASSIGNMENT WITHOUT FINISHING THE
FIRST. MR. DOUGLAS WILL CHECK OFF IF YOU HAVE TURNED IN THE ASSIGNMENT
AND GIVE YOU THE NEXT.
Birds are Oviparous animals, they have small uterus (portion where child grow in viviparous animals), just due to that, they lay seeds than breed
Hope this helps!