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:
“There is hardly a man clever enough to recognize the full extent of the evil he does.”
—François, Duc De La Rochefoucauld (1613–1680)
“The West is preparing to add its fables to those of the East. The valleys of the Ganges, the Nile, and the Rhine having yielded their crop, it remains to be seen what the valleys of the Amazon, the Plate, the Orinoco, the St. Lawrence, and the Mississippi will produce. Perchance, when, in the course of ages, American liberty has become a fiction of the past,—as it is to some extent a fiction of the present,—the poets of the world will be inspired by American mythology.”
—Henry David Thoreau (1817–1862)
“We are frequently told that talents and genius are natural gifts; and so indeed they are, to the same extent that the productions of the garden and the field are natural gifts.”
—U. R., U.S. women’s magazine contributor. American Ladies Magazine, pp. 317-19 (June, 1829)