The "cambrian explosion" refers to a. the creation of earth. b. the development of the first true cell. c. the origination of life. d. the origination of all major phyla of animals. e. the mass extinction of dinosaurs.

The location of the water table is subject to change. select the best answer from the choices provided ot of

Alaska and northern canada have a diet rich in vitamin d and their skin color is darker than predicted on the basis of iv intensity at their latitude. explain the observation:

Can you identify which of the following groups of organisms are, or are not, populations? a. the american bison (bison bison) and grey wolves (canis lupus) currently living in yellowstone national parkb. all of the rainbow trout (oncorhynchus mykiss that) that have ever lived in lake eriec. the group of american bison (bison bison) currently living in yellowstone national parkd. a group of calliope hummingbirds (selasphorus calliope) and a group of rufous hummingbirds (selasphorus rufus) living in the same new hampshire woodse. the northern cardinals (cardinalis cardinalis) living on opposite shores of lake champlain f. all of the whales currently living in the atlantic ocean off cape cod, massachusetts