Weather patterns are caused mainly by the
a) rotation of the earth.
b) uneven heating of the earth.
c) gravitational pull of the moon.
d) distance of the earth’s from the sun.

Asquirrel population lives in an area. over many years, a river in that area grows wider and stronger, eventually forming a canyon. the squirrel populations on the two sides of the canyon can no longer mate with each other and ultimately form distinct species. this is an example of

Which could be a pathway of food through an ecosystem

Which of the following is required of a new drug?me