What do all these changes and transformations teach us? It may be, most importantly, that we still confront what the First Comers faced: the land itself, sea-born and sea-shaped. When we learn its history and observe the age-old forces that continue to work today, the lesson seems to be that any human occupation of the Earth is, at best, tentative and transitory, and particularly so here. The waves, beaches, dunes, and trees of the Cape continue to dance, and we have begun to learn to dance with them—to understand and adapt to the land’s rhythms, tempos, and limits—so that we and those who come after us may continue to enjoy all that it has to offer. For it is we, residents and visitors alike, who are today’s Cape Codders. [Illustration: Wildflowers _White water lily_ _Pink ladyslipper_ _Dewberry_ _Purple aster_ _Seaside goldenrod_ _Beach plum_ _St. Johnswort_ _Sheep laurel_] [Illustration: _Bittersweet nightshade_ _Prickly pear cactus_ _Creeping bellflower_ _Star-flower_ _Beach heather, or poverty grass_ _Beach-pea_ _Canada mayflower_ _Cypress spurge_] ############################################# A Glacial Base [Illustration: (Glaciation map of North America. Moraine deposits on Cape Cod and the Islands. Glacial, post-glacial and present topography.)] The Wisconsin Stage Glacier reached into southern New England 25,000 years ago and melted away more than 17,000 years ago, leaving behind moraine and outwash deposits that became the base of Cape Cod, Martha’s Vineyard, Nantucket, and the Elizabeth Islands (see illustrations at right). But this was only the latest in a series of Pleistocene glaciers that covered Cape Cod during the past 1.5 million years. Even the deposits of these earlier glaciers may rest on a much older and more stable land form, a wide, seaward-sloping surface called a coastal plain or, if submerged, a continental shelf. The plain and shelf are underlain by sediments. The shelf was exposed during the ice ages by a concomitant drop in sea level of some 400-500 feet, but today it lies drowned under rising waters. Even more deeply buried, some 500-800 feet beneath the surface, lies the ancient granite bedrock that is so characteristic of most other New England areas. There is evidence that the post-glacial landscape looked very much like arctic tundra. Deep in the bottom of Truro’s Great Pond, twigs of arctic willow have been retrieved with 11,000-year-old scale insects still attached to the bark. Caribou, arctic fox, and perhaps musk ox, roamed lichen-covered plains where white-tailed deer and red fox live today. Gradually a boreal forest of spruce and fir took root, much like the forests that now cover northern Canada. Outwash Plains and Kettles