Extent
The fauna of the middle Cambrian has a cosmopolitan range. All assemblages preserving soft-part anatomy have a very similar fauna, even though they span almost every continent. The wide distribution has been attributed to the advent of pelagic larvae.
Read more about this topic: Burgess Shale Type Fauna
Famous quotes containing the word extent:
“It is strange to contemplate how little sympathy or encouragement the great mass of people have with one who differs from them in tastes, to the extent of desiring an education, while they are content with little or none.”
—Caroline Nichols Churchill (1833?)