Two plates sliding past each other forms a transform plate boundary. Natural or human-made structures that cross a transform boundary are offset—split into pieces and carried in opposite directions. Rocks that line the boundary are pulverized as the plates grind along, creating a linear fault valley or undersea canyon.
Vertebrate species of the Arctic tundra and polar barrens are limited to mammals and birds; no amphibians or reptiles occur there.
Explanation: